Abstract Renin, as the rate-limiting enzyme in the syn-thesis of the potent vasoactive peptide angiotensin II, hasbeen studied for more than 100 years. Transgenic andknockout mice for renin and other proteins involved inrenin regulation and function have recently revealed newevidence that can improve our understanding of its bio-

logical relevance. Furthermore, transgenic mice havebeen the source of the novel cell line As4.1. This cellline has been effective in the analysis of renin secretionand regulation because of its similarity with renin-pro-ducing juxtaglomerular (JG) cells. Renin secretion andsynthesis by the JG cells of the kidney is upregulated bycAMP and downregulated by intracellular calcium. Theeffect of cGMP, once elevated by nitric oxide, dependson the present level of cAMP in the cells, which can bestimulatory in the presence of and inhibitory in the ab-sence of the other cyclic nucleotides. All known effec-tors of renin regulation affect one of these molecules.Adenosine and ATP, released by macula densa cells inresponse to high salt load in the distal tubule and stretchof the JG cell by renal perfusion pressure, increase calci-um. Furthermore, noradrenaline, derived from sympa-thetic nerve endings, and prostaglandins, generated bymacula densa cells under low-salt conditions, increasecAMP. In addition to its stimulatory effect on secretion,cAMP also effectively augments renin mRNA levels byacting at the transcriptional and posttranscriptional lev-els. Several DNA elements in the distal and proximalpromoter regions as well as in intron I have been impli-cated in cAMP regulation and in tissue specificity of re-nin gene expression. A second intracellular renin iso-form, coded by the same gene but applying a differentpromoter located in intron I, has recently been detected.Transgenic technology will help to clarify the function ofthis isoform as well as some of the other unresolved as-pects of renin regulation and function and may becomethe motor of the second century in renin research.

Key words Renin · Transcriptional regulation · Secretion · Tubuloglomerular feedback · Juxtaglomerularapparatus · Macula densa

Abbreviations Ang:Angiotensin · COX: Cyclo-oxygenase·CRE: cAMP-responsive element · CREB: CRE-bindingprotein · JG: Juxtaglomerular · NOS: NO synthase · NRE: Negative regulatory element · PGE2: Prostaglandin E2 · RAS: Renin-angiotensin system · TGF: Tubuloglomerular feedback

M. Bader (✉) · D. GantenMax Delbrück Center for Molecular Medicine,Robert-Rössle-Strasse 10, 13092 Berlin-Buch, Germanye-mail: mbader@mdc-berlin.deTel.: +49-30-94062193, Fax: 49-30-94062110

D. GantenDepartment of Clinical Pharmacology,University Hospital Benjamin Franklin, Free University Berlin,12200 Berlin, Germany

J Mol Med (2000) 78:130–139Digital Object Identifier (DOI) 10.1007/s00109000089

R E V I E W

Michael Bader · Detlev Ganten

Regulation of renin: new evidence from cultured cellsand genetically modified mice

Received: 11 August 1999 / Accepted: 24 January 2000 / Published online: 31 March 2000© Springer-Verlag 2000

MICHAEL BADERis presently Group Leader atthe Max Delbrück Center forMolecular Medicine, Berlin,Germany. He received hisPh.D. in biology at the Univer-sity of Freiburg, Germany, andhis postdoctoral Habilitationin Medicine at the Free Uni-versity of Berlin. His main re-search interests include the useof transgenic animal models toanalyze the functions of hor-mones involved in cardiovas-cular regulation such as angio-tensin, kinins, and serotonin.

DETLEV GANTENreceived his M.D. from theUniversity of Tübingen andhis Ph.D. from McGill Univer-sity in Montreal, Canada. Heis presently Director of theMax Delbrück Center Berlin-Buch. His research interestsinclude molecular biology andthe function of cardiovasculardiseases.

Introduction

The enzymatic cascade involved in the production of an-giotensin (Ang) II starts with the protease renin catalyz-ing the rate-limiting step from angiotensinogen to Ang I.Circulating renin is synthesized by specialized smoothmuscle cells in the juxtaglomerular (JG) apparatus of thekidney. In these cells the renin gene consisting of 9 ex-ons and 8 introns (in humans and sheep [1] 10 exons dueto the presence of the 9-bp exon 5A) is transcribed;mRNA is processed; and preprorenin, a precursor, istranslocated into the endoplasmic reticulum during trans-lation [2, 3, 4, 5]. In the course of translocation the endo-plasmic reticulum targeting signal sequence is lost, thusyielding the inactive proenzyme prorenin. This protein ishandled by JG cells much as a lysosomal enzyme beingtransported through the Golgi apparatus. It undergoesglycosylation with mannose-6-phosphate residues and isthen stored in lysosome-like secretory granules. Duringtransport the enzyme is activated by cleavage of the pro-sequence. Although there are several suggested candi-dates, including kallikrein [6], cathepsin B [2, 7, 8], andPC5 [9], the responsible prohormone convertase has notbeen characterized. Glycosylation of renin is essentialnot only for storage in secretory granules but also forgeneration of the granules, as revealed in a recent experi-ment in which mice were established with a targeted de-letion of the Ren-1D gene [10]. Mice are unique mam-mals in that there are strains having one renin gene,Ren-1C, and strains bearing two genes, Ren-1D andRen-2. These genes are closely linked on chromosome 1since they originate from an evolutionarily recent geneduplication [3]. Therefore Ren-1D deficient mice still ex-press the Ren-2 gene in JG cells. The protein coded bythis gene has no glycosylation sites, thus remains ungly-cosylated, and is probably sorted to constitutive secreto-ry granules. Absence of the typical electron-dense secre-tory granules in JG cells of Ren-1D deficient mice [10] isdue to lack of a glycosylated renin protein. As expected,Ren-2 deficient mice have normal renin-secretory gran-ules in JG cells [11].

Renin secretion is stimulated by renal sympatheticnerve activity, low renal perfusion pressure, sodium de-pletion, and inhibition of Ang II synthesis or action [2,12]. Renin release under these conditions is mediated bya decrease in intracellular calcium or by an increase incAMP, in contrast to the regulated secretion of other sub-stances depending on elevated intracellular calcium (seebelow). Stimulation of renin secretion from JG cells isthe main regulatory step for the circulating renin-angio-tensin system (RAS) and is accompanied primarily by anincrease in renin mRNA in these cells. Furthermore,some of the renin secretion stimulators also elicit a trans-differentiation mechanism in neighboring smooth musclecells which are “recruited” for renin expression [2, 13].Under maximal stimulatory conditions smooth musclecells along the entire afferent arteriole begin to synthe-size renin. This process recapitulates fetal and early post-natal ontogeny when renin is expressed in most kidney

vessels [14]. The molecular signals involved in this re-cruitment mechanism are poorly understood. However,novel insights into this process are expected from ani-mals deficient in angiotensinogen [15, 16, 17, 18, 19],angiotensin-converting enzyme [20, 21, 22], or Ang IIreceptors of the AT1 type [23, 24]. In mice lacking Ang IIor its main renal receptors not only renin overexpressionbut also smooth muscle hyperplasia is observed in mostbranches of the renovascular tree [18, 21, 22, 24, 25, 26,27]. This is an unexpected phenotype in light of the well-documented growth-promoting actions of Ang II [28, 29,30]. Similar factors causing this effect may also be in-volved in the recruitment process during renin stimula-tion. Platelet-derived growth factor and transforminggrowth factor β1 have been suggested as likely candi-dates [18, 25].

This review focuses principally on recent findingsconcerning the factors and mechanisms controlling reningene expression and secretion. For more comprehensiveinformation, the reader should consult previously pub-lished reviews [2, 3, 4, 31, 32, 33, 34, 35, 36, 37].

Regulatory factors for renin release and expression

Sympathetic nerve activity

Sympathetic nerve endings are found in close proximity toJG cells which express β1-adrenergic receptors (Fig. 1).Stimulation of these receptors by circulating or locallyreleased catecholamines activates adenylyl cyclase andincreases intracellular cAMP, thereby stimulating reninrelease and synthesis [38]. This pathway is one of thebest documented mechanisms of renin regulation andmay exert a tonic stimulatory influence on renin synthe-sis and secretion [39]. However, it affects renin-synthe-sizing cells only in the vicinity of the JG apparatuswhere nerve endings are localized, since these are theonly cells that express β1-adrenergic receptors [12].Smooth muscle cells along other parts of the afferent ar-teriole are not responsive when they bear renin granula,and nonexpressing cells cannot be recruited for reninproduction by catecholamines [38].

Salt load

Substantial information has accumulated confirming theearly postulates of Goormaghtigh [40] and Vander [41]that the macula densa is the mediator between the distaltubule and JG cells, controlling afferent arteriolar toneand the release of renin. It long remained unclear wheth-er the NaCl concentration in the distal tubule is correlat-ed positively or negatively with renin secretion. Further-more, the signaling pathway in the macula densa remainselusive. It is well known that decreases in distal tubularsodium chloride are sensed by macula densa cells whichsubsequently cause vasodilation of the afferent arteriole(tubuloglomerular feedback, TGF) and stimulate renin

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ent arteriole by cAMP diminution and calcium-mediatedmuscle contraction. It is also possible that activation ofthe contractile machinery is responsible for the calcium-mediated inhibition of renin secretion in JG cells be-cause the contracting filaments may physically hinderthe fusion of renin-storage granules with the plasmamembrane [2, 36, 46, 47]. Nitric oxide constitutivelyproduced by the neuronal isoform of NO synthase (NOSI) present in the macula densa [48, 49] partially counter-acts any contractile effect. Simultaneously it inhibits therelease of renin by increasing cGMP in JG cells.

Recent evidence from mice deficient in cGMP-depen-dent protein kinase II shows that cGMP inhibits renin se-cretion via activation of this enzyme [50]. When thecGMP-signaling pathway of NO is blocked, reninmRNA levels are higher in the mouse kidney resulting inelevated renin secretion rates of isolated JG cells. How-ever, elevation in cAMP, for example, by β-adrenergic(see above) or prostaglandin receptor stimulation, cancounteract a direct cGMP effect. Under these conditionsan indirect effect of cGMP, such as inhibition of phos-phodiesterase III may become effective in potentiatingcAMP concentrations and thereby stimulating renin syn-thesis and release [50, 51, 52, 53, 54, 55]. Macula densacells express cyclo-oxygenase (COX) 2 [56, 57], an en-zyme responsible for prostaglandin synthesis whichshows low activity and expression under high-salt condi-tions [58]. However, low-salt concentrations in the distaltubule may lead to reduced activity of the Na/K/2Cl co-transporter and to an increase in intracellular calcium,known to be a potent stimulator of both COX-2 and NOSI. Prostaglandins, such as PGE2, stimulate renin releaseand synthesis via an increase in intracellular cAMP in JGcells [59, 60, 61, 62], probably by EP4 receptors presentin the glomerulus [63, 64, 65]. Thus signaling from themacula densa to JG cells under low-salt conditions mayconsist of both factors, PGE2 and NO. Quite possibly thelatter stimulates the effect of the former by elevatingCOX-2 activity in macula densa cells [66] and increasingthe half-life of its second messenger cAMP in JG cells.Ang II produced via renin secretion in turn exerts a neg-ative feedback on the macula densa cells by inhibitingthe synthesis of NOS I and COX-2 [67, 68]. This may bethe mechanism by which long-term sensitivity of theTGF to varying salt loads is adjusted. Low-sodium dietor volume depletion increases glomerular Ang II produc-tion, thereby decreasing macula densa NOS concentra-tion [69, 70]. All short-term alterations in tubular sodiumload then have a more pronounced effect on afferent ar-teriolar constriction due to a deficiency of the counter-acting vasodilator NO. In contrast, a high-salt diet orvolume expansion decreases Ang II and increases macu-la densa NOS, thus attenuating TGF. For every acutechange in tubular sodium load the vasoconstrictor re-sponse is counterbalanced by a comparable vasodilatoreffect which accompanies NO release. The absence ofTGF [71, 72, 73] and increased levels of macula densaNOS in mice lacking angiotensinogen [74] or AT1A re-ceptors [75], as well as low renin levels and fully pre-

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secretion by JG cells [42]. The exact mechanism of thisresponse is still a matter of intensive debate, and thereader is referred to recent reviews discussing this sub-ject [12, 43, 44, 45]. Figure 1 depicts a scenario whichcomplies with most of the available evidence. A high saltload at the luminal side of the macula densa causes therelease of a potent vasoconstrictor substance, probablyadenosine or ATP. This substance acting via A1 or P2 re-ceptors, respectively, narrows the diameter of the affer-

Fig. 1 Regulation of renin secretion and synthesis in juxtaglomer-ular (JG) cells of the kidney. Under high distal tubular salt loadthe Na+/K+/2Cl– cotransporter in macula densa cells increasesCa2+ levels in JG cells via adenosine or ATP, thereby inhibiting re-nin secretion. Under low distal tubular salt load NO and PGE2 arereleased by the macula densa cells, increasing cAMP levels in JGcells and thereby stimulating renin secretion. Sympathetic nervesstimulate renin secretion by β1-adrenergic receptors coupled tocAMP synthesis and stretch inhibits renin release by increasing in-tracellular calcium in JG cells. A more detailed description ofthese mechanisms is given in the text. For clarity of the presenta-tion all effects of other cells present in the JG apparatus that arepossible but ill-defined, such as podocytes, mesangial, endothelial,and contractile smooth muscle cells, are omitted from this scheme.A1 Adenosine A1 receptor; AA arachidonic acid; AC adenylyl cy-clase; ACE angiotensin-converting enzyme; Ang angiotensin; AT1angiotensin II receptor AT1; β1 β1-adrenergic receptor; cGKIIcGMP-dependent kinase II; COX-2 cyclo-oxygenase 2; EP4 pros-taglandin E2 receptor EP4; L-Arg L-arginine; NA noradrenaline;NOS I neuronal nitric oxide synthase; P2 purinoceptor P2; PDEIIIphosphodiesterase III; PGE2 prostaglandin E2; sGC soluble gua-nylyl cyclase

served TGF in NOS I deficient animals [45], all supportthis notion. In spite of this the macula densa pathway islimited to renin-producing cells in close proximity to theJG apparatus because short-lived autacoids released bythe macula densa can reach only neighboring cells [2]. Itis therefore not responsible for long-lasting increases inrenin production nor for recruitment of new renin-syn-thesizing cells observed under a low-salt diet.

Renal perfusion pressure

The most powerful stimulus for renin secretion is a re-duction in renal perfusion pressure. Recently it has beenshown that pressure, not flow, reduces the release of re-nin from JG cells, excluding involvement of endothelialcells activated by shear stress [76]. Obviously, a stretchreceptor mechanism in JG cells is responsible for the de-crease in renin secretion, most likely by increasing intra-cellular calcium in response to increased perfusion pres-sure [77] (Fig. 1). An increase in intracellular calciumalso induces contraction of smooth muscle cells in theJG apparatus, which retain their contractile function.This leads to myogenic vasoconstriction of the afferentarteriole in response to high blood pressure, which is thesecond pathway of the TGF. In addition to, increasedperfusion pressure increases sodium load to the luminalside of the macula densa, eliciting the previously men-tioned mechanisms which reduce renin release and fur-ther constrict the afferent arteriole. The myogenic re-sponse of afferent arteriolar smooth muscle cells is notrestricted to the JG area. Therefore it is a candidatemechanism for recruitment of smooth muscle cells tosynthesize renin under low renal perfusion pressure.

Angiotensin II

In addition to stimulating renin release under low-saltconditions by a negative feedback mechanism on themacula densa (see above), Ang II also has a direct inhib-itory effect on renin secretion and gene expression byAT1 receptors on JG cells in culture. Whether this short-loop feedback mechanism is physiologically relevant isstill a matter of debate [78]. There are numerous reportsof increases in renin secretion and expression in whichAng II synthesis or receptors are pharmacologicallyblocked in vivo. However, these studies are not conclu-sive because renal perfusion pressure, sympathetic out-put, and distal tubular sodium load were changed in mostof the experiments. Furthermore, an even positive feed-back on Ang II synthesis has been reported from ratschronically infused with Ang II [79]. Recently knockouttechnology has provided a means of producing chimericmice with tissues consisting of patches of cells eithercarrying or lacking AT1A receptors [80]. Renin expres-sion in the kidneys of these animals was identical in allnephrons irrespective of the presence or absence of theAT1A receptor. This indicates that systemic influences,

for example, blood pressure, may be stronger than localAng II effects on JG cells.

Other factors

Several other factors have been implicated in regulationof renin synthesis and secretion (reviewed in [2]). Twonew candidates were recently added to this list after thefindings that adrenomedullin upregulates renin probablyby increasing intracellular cAMP [81], and that interleu-kin-1β inhibits renin expression by a mechanism inde-pendent of the sympathetic nervous system [82]. Thephysiological role of these factors, however, remainsconjectural.

Regulatory elements for transcription

The most obvious features of renin transcription are (a)its strong inducibility by cAMP, which seems to be themajor intracellular regulator for renin expression con-trolled by the above mechanisms and (b) its striking tis-sue specificity. With the exception of mouse strains car-rying the Ren-2 gene, which is expressed at high levelsin the submandibular gland [83], by far the highest ex-pression of renin genes is observed in kidney JG cellsfrom all mammals studied thus far. Much lower levelshave been found in other tissues, where it exerts impor-tant physiological functions by initiating the local organ-based RAS (for reviews see [4, 84, 85, 86, 87, 88]).

The study of renin transcription has been difficult be-cause of a lack of suitable cell lines. In the past most ex-periments have utilized renin-secreting cell lines fromextrarenal renin-production sites and non-renin-express-ing cells. Recently Sigmund et al. [89] isolated As4.1cells, which resemble JG cells and secrete renin into cul-ture medium [90], by expressing the SV40-T antigen,under the control of the Ren-2 promoter, in transgenicmice. These have been used to map relevant transcrip-tional regulatory elements in the murine Ren-1C gene(Fig. 2) [91]; however, the fact that the SV40-T antigentransforming these cells is also under control of a reninpromoter may create problems in interpreting the results.

Proximal regulatory elements

Several cAMP-responsive elements (CRE) have been de-scribed in the proximal promoter regions of renin genesin various species (Fig. 2) [5]. At position –226 to –219in the human renin gene a CRE was detected and foundto be functional in chorionic [92, 93] and Calu-6 lungcarcinoma cells [94, 95] through interaction with CRE-binding protein (CREB) and stimulation of transcription.For optimal activity of the CRE a DNA element must bepresent at positions –77 to –67, with homologies to bind-ing sites for POU domain transcription factors [92, 93,94, 95, 96, 97, 98, 99]. An analogous element also in-

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volved in cAMP regulation has been found in the proxi-mal promoter of the mouse Ren-1C gene (RP-2, –75 to–47) [100, 101]. This sequence confers activation of re-nin gene expression via the product of the retinoblastomagene, RB [102], and seems to be involved in tissue-spe-cific regulation exerted by a distal enhancer [91].

Recently, Tamura et al. [103, 104] described an AP-1element immediately 5′ of the transcription start site ofthe mouse Ren-1C gene (RC, –36 to –20) which is re-sponsive to c-jun and may be involved in basic renin ex-pression.

Another CRE has been detected further upstream onthe Ren-1D promoter (–626 to –599). This CRE is in-volved in tissue-specific gene expression through inter-action with an overlapping negative regulatory element(NRE, -607 to –589; Fig. 2) [105, 106, 107, 108, 109].When intracellular cAMP rises in the kidney, CRE bindsCREB and stimulates renin gene expression by displac-ing an NRE-binding protein. In other organs CREB is in-activated by tissue-specific factors, and transcription ofRen-1D is blocked by NRE- binding protein. This mecha-nism also explains the high and cAMP-independent tran-scriptional activity of the Ren-2 gene in the mouse sub-mandibular gland. In this gene the NRE is interruptedand consequently inactivated by a 150-bp insertion[108].

Distal enhancers

Transgenic experiments have shown that DNA sequenc-es both in the promoter and in transcribed regions of theRen-2 gene are necessary for correct tissue specificity ofexpression. Transgenic mice with 5.3 [110] or 2.5 kb[111, 112] of the promoter region and all exons and int-rons, or with a 4.6-kb promoter fragment and SV40 T-antigen as a reporter gene, express the transgene correct-ly in the kidneys, genital organs, submandibular and ad-renal glands; transformed renin-producing cells can bedeveloped from these mice [89, 113, 114, 115, 116]. Ani-mals with only 2.5 kb of the promoter and the same re-porter gene, however, show ectopic expression and donot develop renin-producing tumors [117]. Thus thereappears to be some redundancy of tissue-specific ele-ments in the promoter and in the transcribed region since2.5 kb of promoter are only sufficient for correct expres-sion in concert with all exons and introns, while longer5′-flanking regions are independent of other parts of theRen-2 gene. Comparable results have also been pub-lished for the Ren-1D gene since 5 kb of the promoterleads to correct expression in transgenic mice predomi-nantly in the kidney in the presence of the entire tran-scribed region but not fused to a chloramphenicol acetyl-transferase reporter gene [118]. Furthermore, the humanrenin gene is expressed in a partially ectopic pattern intransgenic animals. Gene regulation is inadequate intransgenic mice [119, 120, 121, 122, 123] and rats [124,125] if up to 3 kb of only upstream sequences are includ-ed in the construct. While the kidney is the major tissueof expression, other organs such as the spleen and testis,contain considerable amounts of transgenic mRNA.However, when constructs are used with more than 25 kb5′-flanking sequences, transgene expression is largelyconfined to the kidney and to a lesser extent the lung andother organs which also express renin at low levels inhumans [122, 126, 127, 128]. Furthermore, bilateral ne-phrectomy depletes circulating human renin and proreninin these mice, as expected, while animals with shortertransgene constructs paradoxically show increased plas-

Fig. 2 Regulatory elements in the renin gene. DNA elements re-ported to regulate renin transcription are depicted at the position inthe gene in which they first have been described, irrespective ofthe species. RC, RP2, and RU1 were first described for the Ren-1C

gene, and the CRE/NRE element was detected in the Ren-1D gene.An RP2-like element was also found at the same site in the humangene, and the CRE/NRE element was additionally detected in therat and human gene at various positions. The CRE at –220 wasdemonstrated only in the human gene and intronic regulatory ele-ments have been defined in the rat renin gene. The function ofeach element is described in the text. +1 Transcriptional start site;CRE cAMP-responsive element; I- intronic; NRE negative regula-tory element; PRE positive regulatory element; filled boxes codingregion; hatched boxes noncoding exonic region; filled egg-shapedsymbols positive regulatory elements; open egg-shaped symbolsnegative regulatory elements

ma prorenin levels after the operation [122]. These dif-ferential sources of circulating renin may also be respon-sible for observed differences in blood pressure after co-expression of human angiotensinogen in human renintransgenic animals. Animals with short transgene con-structs become hypertensive [121, 125, 129, 130] andmice with long promoter regions develop either onlyslightly elevated blood pressure or even remain normo-tensive [127, 128]. This indicates that the normal down-regulation of the human renin transgene by elevatedblood pressure (see above) occurs only in animals har-boring long promoter regions.

Recent studies have revealed possible candidates fortissue-specific elements both in the distal promoter andin intron I of the gene (see below). In the mouse Ren-1C

gene a tissue-specific enhancer has been detected 2.7 kbupstream of the transcriptional start site [91]. An homol-ogous region was found to be present about 12 kb up-stream of human renin exon 1 (Fig. 2) [131, 132]. Whilethe functionality of these elements is supported by trans-genic experiments (see above), an enhancer element lo-cated between –5777 and –5552 in the human renin gene(Fig. 2) awaits in vivo confirmation [133].

Intronic silencer

The presence of transcriptional regulatory elements inthe transcribed part of the renin gene have been predict-ed by transgenic experiments (see above). Intron I exhib-its a high degree of interspecies homology, at least in thefirst 120 bp [134, 135], contains consensus sequences forthe binding of transcription factors [136, 137], and isbound by nuclear proteins [138, 139]. Indeed, it has beendemonstrated that intron I of the rat [135] and human re-nin gene [94, 137, 140] exerts a silencing effect on theactivity of homologous and heterologous promoters. Re-cently we showed that the intronic silencer in the rat re-nin gene exhibits a complex structure composed of atleast five distinct negative and two positive regulatoryelements (Fig. 2) [139]. The role of these elements fortissue specificity or inducibility of renin gene expressionwill be the subject of future studies.

Second promoter defining a new renin isoform

Two groups have recently reported another surprisingfinding concerning renin intron I [141, 142]. Several tis-sues, including brain and adrenal gland but not kidney,express a novel renin mRNA isoform probably started bya promoter located in intron I (Fig. 2). This mRNA iso-form contains a novel exon 1 (exon 1A) which carries aputative translational start codon. One group demonstrat-ed that renin protein (renin A) resulting from this iso-form would not contain the signal sequence needed fortargeting to the secretory pathway, would remain intra-cellular, and may be subject to import into mitochondria[142]. An intramitochondrial RAS with important func-

tions in the regulation of steroid hormone synthesis hasbeen postulated [143] for the adrenal gland. To evaluatethe physiological significance of renin A, additionalwork will be required to demonstrate this protein and itsactivity in tissues and to characterize the promoter re-gion responsible for its synthesis.

Posttranscriptional regulation

The enormous increase in renin-mRNA levels aftercAMP stimulation cannot be attributed entirely to theabove transcriptional activation mechanisms. Hence therecent finding that cAMP triples the half-life of reninmRNA in JG and Calu-6 cells [140, 144, 145] was notsurprising. Stabilization of mRNA by cAMP has beenreported for a number of genes, but to now neither con-sensus targeting sequences nor a common mechanismhas been elucidated (see references cited in [146]).Therefore the mechanism of renin-mRNA stabilizationremains elusive.

Future prospects

The first century of renin research has brought signifi-cant insights into its regulation and function. However,there are still many questions that remain unanswered. Inparticular, the intracellular pathways in JG cells whichintegrate cAMP, cGMP, and calcium levels to direct re-nin secretion are far from being completely resolved.The same holds true for signaling inside the macula den-sa which links distal sodium load to the output of adeno-sine, ATP, NO, and PGE2. Furthermore, the role of othercells in the JG region, such as podocytes, mesangial andendothelial cells, in the regulation of renin and TGFawaits clarification. Recruitment of contractile smoothmuscle cells for transdifferentiation into renin-synthesiz-ing cells remains another important topic of future renin-related research as well as the role of reactive oxygenspecies. These radicals may play major roles in glomeru-lar damage, elicited by a permanent increase in renal per-fusion pressure, and an intrarenal RAS may be crucialfor generation. In general the intrarenal effects of reninand angiotensins are not well understood, particularlywhen one considers the fact that renin is secreted first inthe renal interstitium with only a “spill-over” reachingcirculation. Perhaps the second century of renin researchwill help to clarify these questions now that there arenovel transgenic animal models with overexpression orconditional ablation of RAS genes in the kidney [147,148], downregulated RAS genes with tissue-specific ex-pression of antisense RNAs [149], and animals with or-gan-specific restoration of RAS gene expression in aknockout background [150], on the forefront.

Acknowledgements We thank Ora Lockley and Jörg Peters forcritical reading of the manuscript and Dana Lafuente for excellentsecretarial assistance.

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References

1. Aldred GP, Fu P, Crawford RJ, Fernley RT (1992) The se-quence and tissue distribution of ovine renin. J Mol Endo-crinol 8:3–11

2. Hackenthal E, Paul M, Ganten D, Taugner R (1990) Morphol-ogy, physiology, and molecular biology of renin secretion.Physiol Rev 70:1067–1116

3. Morris BJ (1992) Molecular biology of renin I: gene and pro-tein structure, synthesis and processing. J Hypertens 10:209–214

4. Morris BJ (1996) Molecular biology of renin. In: LindpaintnerK, Ganten D (eds) Molecular reviews in cardiovascular medi-cine. Chapman & Hall, London, pp 12–32

5. Tamura K, Umemura S, Fukamizu A, Ishii M, Murakami K(1995) Recent advances in the study of renin and angiotensi-nogen genes: from molecules to the whole body. HypertensRes 18:7–18

6. Kikkawa Y, Yamanaka N, Tada J, Kanamori N, Tsumura K,Hosoi K (1998) Prorenin processing and restricted endoprote-olysis by mouse tissue kallikrein family enzymes (mK1, mK9,mK13, and mK22). Biochim Biophys Acta 1382:55–64

7. Neves FA, Duncan KG, Baxter JD (1996) Cathepsin B is aprorenin processing enzyme. Hypertension 27:514–517

8. Jutras I, Reudelhuber TL (1999) Prorenin processing by ca-thepsin B in vitro and in transfected cells. FEBS Lett 443:48–52

9. Laframboise M, Reudelhuber TL, Jutras I, Brechler V, SeidahNG, Day R, Gross KW, Deschepper CF (1997) Prorenin acti-vation and prohormone convertases in the mouse As4.1 cellline. Kidney Int 51:104–109

10. Clark AF, Sharp MGF, Morley SD, Fleming S, Peters J,Mullins JJ (1997) Renin-1 is essential for normal renal juxta-glomerular cell granulation and macula densa morphology. JBiol Chem 272:18185–18190

11. Sharp MG, Fettes D, Brooker G, Clark AF, Peters J, FlemingS, Mullins JJ (1996) Targeted inactivation of the Ren-2 genein mice. Hypertension 28:1126–1131

12. Wagner C, Kurtz A (1998) Regulation of renal renin release.Curr Opin Nephrol Hypertens 7:437–441

13. Gomez RA, Chevalier RL, Everett AD, Elwood JP, Peach MJ,Lynch KR, Carey RM (1990) Recruitment of renin gene-ex-pressing cells in adult rat kidneys. Am J Physiol 259:F660–F665

14. Gomez RA, Tufro-McReddie A, Everett AD, Pentz ES (1993)Ontogeny of renin and AT1 receptor in the rat. Pediatr Nephrol7:635–638

15. Tanimoto K, Sugiyama F, Goto Y, Ishida J, Takimoto E,Yagami K, Fukamizu A, Murakami K (1994) Angiotensinogen-deficient mice with hypotension. J Biol Chem 269:31334–31337

16. Smithies O, Kim H-S (1994) Targeted gene duplication anddisruption for analyzing quantitative genetic traits in mice.Proc Natl Acad Sci USA 91:3612–3615

17. Kim H-S, Krege JH, Kluckman KD, Hagaman JR, Hodgin JB,Best CF, Jennette JC, Coffman TM, Maeda N, Smithies O(1995) Genetic control of blood pressure and the angiotensino-gen locus. Proc Natl Acad Sci USA 92:2735–2739

18. Niimura F, Labosky PA, Kakuchi J, Okubo S, Yoshida H,Oikawa T, Ichiki T, Naftilan AJ, Fogo A, Inagami T, HoganBLM, Ichikawa I (1995) Gene targeting in mice reveals a re-quirement for angiotensin in the development and mainte-nance of kidney morphology and growth factor regulation. JClin Invest 96:2947–2954

19. Kim H-S, Maeda N, Oh GT, Fernandez LG, Gomez RA,Smithies O (1999) Homeostasis in mice with genetically de-creased angiotensinogen is primarily by an increased numberof renin-producing cells. J Biol Chem 274:14210–14217

20. Krege JH, John SW, Langenbach LL, Hodgin JB, HagamanJR, Bachman ES, Jennette JC, O’Brien DA, Smithies O (1995)Male-female differences in fertility and blood pressure inACE-deficient mice. Nature 375:146–148

21. Esther CR, Marino EM, Howard TE, Machaud A, Corvol P,Capecchi MR, Bernstein KE (1997) The critical role of tissueangiotensin-converting enzyme as revealed by gene targetingin mice. J Clin Invest 99:2375–2385

22. Carpenter C, Honkanen AA, Mashimo H, Goss KA, Huang P,Fishman MC, Asaad M, Dorso CR, Cheung H (1996) Renalabnormalities in mutant mice. Nature 380:292

23. Tsuchida S, Matsusaka T, Chen X, Okubo S, Niimura F,Nishimura H, Fogo A, Utsunomiya H, Inagami T, Ichikawa I(1998) Murine double nullizygotes of the angiotensin type 1Aand 1B receptor genes duplicate severe abnormal phenotypesof angiotensinogen nullizygotes. J Clin Invest 101:755–760

24. Oliverio MI, Kim HS, Ito M, Le T, Audoly L, Best CF, HillerS, Kluckman K, Maeda N, Smithies O, Coffman TM (1998)Reduced growth, abnormal kidney structure, and type 2 (AT2)angiotensin receptor-mediated blood pressure regulation inmice lacking both AT1A and AT1B receptors for angiotensinII. Proc Natl Acad Sci USA 95:15496–15501

25. Nagata M, Tanimoto K, Fukamizu A, Kon Y, Sugiyama F,Yagami K, Murakami K, Watanabe T (1996) Nephrogenesisand renovascular development in angiotensinogen-deficientmice. Lab Invest 75:745–753

26. Coffman TM (1998) Gene targeting in physiological investiga-tions: studies of the renin-angiotensin system. Am J Physiol274:F999–F1005

27. Esther CR Jr, Howard TE, Marino EM, Goddard JM, CapecchiMR, Bernstein KE (1996) Mice lacking angiotensin-convert-ing enzyme have low blood pressure, renal pathology, and re-duced male fertility. Lab Invest 74:953–965

28. Peach MJ, Dostal DE (1990) The angiotensin II receptor andthe actions of angiotensin II. J Cardiovasc Pharmacol 16[Suppl 4]:S25–S30

29. Paul M, Ganten D (1992) The molecular basis of cardiovascu-lar hypertrophy: the role of the renin angiotensin system. JCardiovasc Pharmacol 19 [Suppl 5]:S51–S58

30. Huckle WR, Earp HS (1994) Regulation of cell proliferationand growth by angiotensin II. Prog Growth Factor Res5:177–194

31. Sigmund CD, Gross KW (1991) Structure, expression, andregulation of the murine renin genes. Hypertension 18:446–457

32. Sigmund CD, Fabian JR, Gross KW (1992) Expression andregulation of the renin gene. Trends Cardiovasc Med 2:237–245

33. Morris BJ (1992) Molecular biology of renin II: gene controlby messenger RNA, transfection and transgenic studies. J Hy-pertens 10:337–342

34. della Bruna R, Kurtz A, Schricker K (1996) Regulation of re-nin synthesis in the juxtaglomerular cells. Curr Opin NephrolHypertens 5:16–19

35. Kurtz A, Wagner C (1999) Cellular control of renin secretion.J Exp Biol 202:219–225

36. Kurtz A, Wagner C (1999) Regulation of renin secretion byangiotensin II-AT1 receptors. J Am Soc Nephrol 10:S162–S168

37. Kurtz A, Wagner C (1998) Role of nitric oxide in the controlof renin secretion. Am J Physiol 275:F849–F862

38. Holmer SR, Kaissling B, Putnik K, Pfeifer M, Kramer BK,Riegger GA, Kurtz A (1997) Beta-adrenergic stimulation ofrenin expression in vivo. J Hypertens 15:1471–1479

39. Wagner C, Hinder M, Krämer BK, Kurtz A (1999) Role of re-nal nerves in the stimulation of the renin system by reducedrenal arterial pressure. Hypertension 34:1101–1105

40. Goormaghtigh N (1937) L’appareil neuromyo-arteriel juxta-glomerulaire du rein; ses reactions en pathologie et ses rap-ports avec le tube urinifere. C R Soc Biol 124:293–296

41. Vander AJ (1967) Control of renin release. Physiol Rev 47:359–382

42. Skøtt O, Briggs JP (1987) Direct demonstration of maculadensa-mediated renin secretion. Science 237:1618–1620

43. Wilcox CS (1998) Role of macula densa NOS in tubuloglom-erular feedback. Curr Opin Nephrol Hypertens 7:443–449

136

44. Navar LG (1998) Integrating multiple paracrine regulators ofrenal microvascular dynamics. Am J Physiol 274:F433–F444

45. Schnermann J (1998) Juxtaglomerular cell complex in the reg-ulation of renal salt excretion. Am J Physiol 274:R263–R279

46. Park CS, Chang SH, Lee HS, Kim SH, Chang JW, Hong CD(1996) Inhibition of renin secretion by Ca2+ through activa-tion of myosin light chain kinase. Am J Physiol 271:C242–C247

47. Park CS, Lee HS, Chang SH, Honeyman TW, Hong CD(1996) Inhibitory effect of Ca2+ on renin secretion elicited bychemiosmotic stimuli through actomyosin mediation. Am JPhysiol 271:C248–C254

48. Mundel P, Bachmann S, Bader M, Fischer A, Kummer W,Mayer B, Kriz W (1992) Expression of nitric oxide synthasein kidney macula densa cells. Kidney Int 42:1017–1019

49. Wilcox CS, Welch WJ, Murad F, Gross SS, Taylor G, Levi R,Schmidt HHHW (1992) Nitric oxide synthase in macula densaregulates glomerular capillary pressure. Proc Natl Acad SciUSA 89:11993–11997

50. Wagner C, Pfeifer A, Ruth P, Hofmann F, Kurtz A (1998) Roleof cGMP-kinase II in the control of renin secretion and reninexpression. J Clin Invest 102:1576–1582

51. Chiu T, Reid IA (1996) Role of cyclic GMP-inhibitable phos-phodiesterase and nitric oxide in the beta adrenoceptor controlof renin secretion. J Pharmacol Exp Ther 278:793–799

52. Kurtz A, Gotz KH, Hamann M, Wagner C (1998) Stimulationof renin secretion by nitric oxide is mediated by phosphodies-terase 3. Proc Natl Acad Sci USA 95:4743–4747

53. Beierwaltes WH (1997) Macula densa stimulation of renin isreversed by selective inhibition of neuronal nitric oxide syn-thase. Am J Physiol 272:R1359–R1364

54. Schnackenberg CG, Tabor BL, Strong MH, Granger JP (1997)Inhibition of intrarenal NO stimulates renin secretion througha macula densa-mediated mechanism. Am J Physiol 272:R879–R886

55. della Bruna R, Kurtz A, Corvol P, Pinet F (1993) ReninmRNA quantification using polymerase chain reaction in cul-tured juxtaglomerular cells. Short-term effects of cAMP on re-nin mRNA and secretion. Circ Res 73:639–648

56. Harris RC, McKanna JA, Akai Y, Jacobson HR, Dubois RN,Breyer MD (1994) Cyclooxygenase-2 is associated with themacula densa of rat kidney and increases with salt restriction.J Clin Invest 94:2504–2510

57. Hartner A, Goppelt-Strübe M, Hilgers KF (1998) Coordinateexpression of cyclooxygenase-2 and renin in the rat kidney inrenovascular hypertension. Hypertension 31:201–205

58. Yang T, Singh I, Pham H, Sun D, Smart A, Schnermann JB,Briggs JP (1998) Regulation of cyclooxygenase expression inthe kidney by dietary salt intake. Am J Physiol 274:F481–F489

59. Greenberg SG, Lorenz JN, He XR, Schnermann JB, Briggs JP(1993) Effect of prostaglandin synthesis inhibition on maculadensa-stimulated renin secretion. Am J Physiol 265:F578–F883

60. Jensen BL, Schmid C, Kurtz A (1996) Prostaglandins stimu-late renin secretion and renin mRNA in mouse renal juxta-glomerular cells. Am J Physiol 271:F659–F669

61. Harding P, Sigmon DH, Alfie ME, Huang PL, Fishman MC,Beierwaltes WH, Carretero OA (1997) Cyclooxygenase-2 me-diates increased renal renin content induced by low-sodium di-et. Hypertension 29:297–302

62. Traynor TR, Smart A, Briggs JP, Schnermann J (1999) Inhibi-tion of macula densa-stimulated renin secretion by pharmaco-logical blockade of cyclooxygenase-2. Am J Physiol 277:F706–F710

63. Breyer MD, Davis L, Jacobson HR, Breyer RM (1996) Differ-ential localization of prostaglandin E receptor subtypes in hu-man kidney. Am J Physiol 270:F912–F918

64. Breyer MD, Zhang Y, Guan YF, Hao CM, Hebert RL, BreyerRM (1998) Regulation of renal function by prostaglandin E re-ceptors. Kidney Int Suppl 67:S88–S94

65. Sugimoto Y, Namba T, Shigemoto R, Negishi M, Ichikawa A,Narumiya S (1994) Distinct cellular localization of mRNAsfor three subtypes of prostaglandin E receptor in kidney. Am JPhysiol 266:F823–F828

66. Salvemini D, Misko TM, Masferrer JL, Seibert K, Currie MG,Needleman P (1993) Nitric oxide activates cyclooxygenaseenzymes. Proc Natl Acad Sci USA 90:7240–7244

67. Wolf K, Castrop H, Hartner A, Goppelt-Strübe M, Hilgers KF,Kurtz A (1999) Inhibition of the renin-angiotensin system up-regulates cyclooxygenase-2 expression in the macula densa.Hypertension 34:503–507

68. Chang HF, Wang JL, Zhang MZ, Miyazaki Y, Ichikawa I,McKanna JA, Harris RC (1999) Angiotensin II attenuates re-nal cortical cyclooxygenase-2 expression. J Clin Invest 103:953–961

69. Schricker K, Hegyi I, Hamann M, Kaissling B, Kurtz A (1995)Tonic stimulation of renin gene expression by nitric oxide iscounteracted by tonic inhibition through angiotensin II. ProcNatl Acad Sci USA 92:8006–8010

70. Ichihara A, Imig JD, Navar LG (1999) Neuronal nitric oxidesynthase-dependent afferent arteriolar function in angiotensinII-induced hypertension. Hypertension 33:462–466

71. Schnermann JB, Traynor T, Yang T, Huang YG, Oliverio MI,Coffman T, Briggs JP (1997) Absence of tubuloglomerularfeedback responses in AT1A receptor-deficient mice. Am JPhysiol 273:F315–F320

72. Traynor T, Yang TX, Huang YG, Arend L, Oliverio MI, Coff-man T, Briggs JP, Schnermann J (1998) Inhibition of adeno-sine-1 receptor-mediated preglomerular vasoconstriction in AT(1A) receptor-deficient mice. Am J Physiol 44:F922–F927

73. Traynor TR, Schnermann J (1999) Renin-angiotensin systemdependence of renal hemodynamics in mice. J Am Soc Nephr-ol 10 [Suppl 11]:S184–S188

74. Kihara M, Umemura S, Kadota T, Yabana M, Tamura K,Nyuui N, Ogawa N, Murakami K, Fukamizu A, Ishii M (1997)The neuronal isoform of constitutive nitric oxide synthase isup-regulated in the macula densa of angiotensinogen gene-knockout mice. Lab Invest 76:285–294

75. Kihara M, Umemura S, Sugaya T, Toya Y, Yabana M, Kobay-ashi S, Tamura K, Kadota T, Kishida R, Murakami K,Fukamizu A, Ishii M (1998) Expression of neuronal type nitricoxide synthase and renin in the juxtaglomerular apparatus ofangiotensin type-1a receptor gene-knockout mice. Kidney Int53:1585–1593

76. Nafz B, Berthold H, Ehmke H, Hackenthal E, Kirchheim HR,Persson PB (1997) Flow versus pressure in the control of reninrelease in conscious dogs. Am J Physiol 273:F200–F205

77. Carey RM, McGrath HE, Pentz ES, Gomez RA, Barrett PQ(1997) Biomechanical coupling in renin-releasing cells. J ClinInvest 100:1566–1574

78. Schricker K, Holmer S, Kramer BK, Riegger GA, Kurtz A(1997) The role of angiotensin II in the feedback control of re-nin gene expression. Pflugers Arch 434:166–172

79. Zou LX, Imig JD, von Thun AM, Hymel A, Ono H, Navar LG(1996) Receptor-mediated intrarenal angiotensin II augmenta-tion in angiotensin II-infused rats. Hypertension 28:669–677

80. Matsusaka T, Nishimura H, Utsunomiya H, Kakuchi J,Niimura F, Inagami T, Fogo A, Ichikawa I (1996) Chimericmice carrying ‘regional’ targeted deletion of the angiotensintype 1A receptor gene. Evidence against the role for local an-giotensin in the in vivo feedback regulation of renin synthesisin juxtaglomerular cells. J Clin Invest 98:1867–1877

81. Jensen BL, Kramer BK, Kurtz A (1997) Adrenomedullin stim-ulates renin release and renin mRNA in mouse juxtaglomeru-lar granular cells. Hypertension 29:1148–1155

82. Petrovic N, Kane CM, Sigmund CD, Gross KW (1997) Down-regulation of renin gene expression by interleukin-1. Hyper-tension 30:230–235

83. Kon Y, Endoh D (1999) Renin in exocrine glands of differentmouse strains. Anat Histol Embryol 28:239–242

84. Campbell DJ (1987) Circulating and tissue angiotensin sys-tems. J Clin Invest 79:1–6

137

85. Phillips MI, Speakman EA, Kimura B (1993) Levels of an-giotensin and molecular biology of the tissue renin angioten-sin systems. Regul Pept 43:1–20

86. Bader M, Paul M, Fernandez-Alfonso M, Kaling M, GantenD (1994) Molecular biology and biochemistry of the renin-angiotensin system. In: Swales JD (ed) Textbook of hyperten-sion. Blackwell, Oxford, pp 214–232

87. Paul M, Bachmann J, Ganten D (1992) The tissue renin-an-giotensin systems in cardiovascular disease. Trends Cardio-vasc Med 2:94–99

88. Bader M, Wagner J, Lee M, Ganten D (1994) The role of therenin-angiotensin system in cardiovascular disease. Hyper-tens Res 17:1–16

89. Sigmund CD, Okuyama K, Ingelfinger J, Jones CA, MullinsJJ, Kane C, Kim U, Wu C, Kenny L, Rustum Y, Dzau VJ,Gross KW (1990) Isolation and characterization of renin-ex-pression cell lines from transgenic mice containing a renin-promoter viral oncogene fusion construct. J Biol Chem 265:19916–19922

90. Jones CA, Petrovic N, Novak EK, Swank RT, Sigmund CD,Gross KW (1997) Biosynthesis of renin in mouse kidney tu-mor As4.1 cells. Eur J Biochem 243:181–190

91. Petrovic N, Black TA, Fabian JR, Kane C, Jones CA, LoudonJA, Abonia JP, Sigmund CD, Gross KW (1996) Role of prox-imal promoter elements in regulation of renin gene transcrip-tion. J Biol Chem 271:22499–22505

92. Germain S, Konoshita T, Philippe J, Corvol P, Pinet F (1996)Transcriptional induction of the human renin gene by cyclicAMP requires cyclic AMP response element-binding protein(CREB) and a factor binding a pituitary-specific trans-actingfactor (Pit-1) motif. Biochem J 316:107–113

93. Germain S, Konoshita T, Fuchs S, Philippe J, Corvol P, PinetF (1997) Regulation of human renin gene transcription bycAMP. Clin Exp Hypertens 19:543–550

94. Germain S, Philippe J, Fuchs S, Lengronne A, Corvol P,Pinet F (1997) Regulation of human renin secretion and genetranscription in Calu-6 cells. FEBS Lett 407:177–183

95. Ying L, Morris BJ, Sigmund CD (1997) Transactivation ofthe human renin promoter by the cyclic AMP/protein kinaseA pathway is mediated by both cAMP-responsive elementbinding protein-1 (CREB)-dependent and CREB-independentmechanisms in Calu-6 cells. J Biol Chem 272:2412–2420

96. Sun J, Oddoux C, Gilbert MT, Yan Y, Lazarus A, CampbellWG, Catanzaro DF (1994) Pituitary specific transcriptionfactor (Pit-1) binding site in the human renin gene 5’-flank-ing DNA stimulates promoter activity in placental cell prima-ry cultures and pituitary lactosomatotropic cell lines. CircRes 75:624–629

97. Borensztein P, Germain S, Fuchs S, Philippe J, Corvol P,Pinet F (1994) Cis-regulatory elements and trans-acting fac-tors directing basal and cAMP-stimulated human renin geneexpression in chorionic cells. Circ Res 74:764–773

98. Gilbert MT, Sun J, Yan Y, Oddoux C, Lazarus A, Tansey WP,Lavin TN, Catanzaro DF (1994) Renin gene promoter activi-ty in GC cells is regulated by cAMP and thyroid hormonethrough Pit-1-dependent mechanisms. J Biol Chem 269:28049–28054

99. Sun J, Oddoux C, Lazarus A, Gilbert MT, Catanzaro DF(1993) Promoter activity of human renin 5’-flanking DNAsequences is activated by the pituitary-specific transcriptionfactor Pit-1. J Biol Chem 268:1505–1508

100. Tamura K, Umemura S, Yamaguchi S, Iwamoto T, KobayashiS, Fukamizu A, Murakami K, Ishii M (1994) Mechanism ofcAMP regulation of renin gene transcription by proximalpromoter. J Clin Invest 94:1959–1967

101. Tamura K, Tanimoto K, Murakami K, Fukamizu A (1993) Acombination of upstream and proximal elements is requiredfor efficient expression of the mouse renin promoter in cul-tured cells. Nucleic Acids Res 20:3617–3623

102. Tamura K, Umemura S, Nyui N, Yamaguchi S, Ishigami T,Hibi K, Yabana M, Kihara M, Fukamizu A, Murakami K,Ishii M (1997) A novel proximal element mediates the regu-

lation of mouse Ren-1C promoter by retinoblastoma proteinin cultured cells. J Biol Chem 272:16845–16851

103. Tamura K, Tanimoto K, Murakami K, Fukamizu A (1993)Activation of mouse renin promoter by cAMP and c-Jun in akidney-derived cell line. Biochim Biophys Acta 1172:306–310

104. Tamura K, Umemura S, Nyui N, Yabana M, Toya Y,Fukamizu A, Murakami K, Ishii M (1998) Possible role of c-Jun in transcription of the mouse renin gene. Kidney Int54:382–393

105. Horiuchi M, Nakamura N, Tang S-S, Barrett G, Dzau VJ(1991) Molecular mechanism of tissue-specific regulation ofmouse renin gene expression by cAMP. Identification of aninhibitory protein that binds nuclear transcriptional factor. JBiol Chem 266:16247–16254

106. Barrett GL, Horiuchi M, Paul M, Nakamura N, Pratt RE,Dzau VJ (1992) Identification of a negative element involvedin tissue specific expression of mouse renin genes. Proc NatlAcad Sci USA 89:885–889

107. Horiuchi M, Pratt RE, Nakamura N, Dzau VJ (1993) Distinctnuclear proteins competing for an overlapping sequence ofcAMP and negative-regulatory elements regulate tissue-specif-ic mouse renin gene expression. J Clin Invest 92:1805–1811

108. Yamada T, Horiuchi M, Morishita R, Zhang L, Pratt RE,Dzau VJ (1995) In vivo identification of a negative regulato-ry element in the mouse renin gene using direct gene transfer.J Clin Invest 96:1230–1237

109. Tomita S, Tomita N, Yamada T, Zhang L, Kaneda Y,Morishita R, Ogihara T, Dzau VJ, Horiuchi J (2000) Tran-scription factor decoy to study the molecular mechanism ofnegative regulation of renin gene expression in the liver in vi-vo. Circ Res 84:1059–1066

110. Mullins JJ, Sigmund CD, Kane-Haas C, McGowan RA,Gross KW (1989) Expression of the DBA/2 J Ren-2 gene inthe adrenal gland of transgenic mice. EMBO J 8:4065–4072

111. Tronik D, Rougeon F (1988) Thyroxine and testosteronetranscriptionally regulate renin gene expression in the sub-maxillary gland of normal and transgenic mice carrying extracopies of the Ren2 gene. FEBS Lett 234:336–340

112. Tronik D, Dreyfus M, Babinet C, Rougeon F (1987) Regulat-ed expression of the Ren-2 gene in transgenic mice derivedfrom parental strains carrying only the Ren-1 gene. EMBO J6:983–987

113. Jacob HJ, Sigmund CD, Shockley TR, Gross KW, Dzau VJ(1991) Renin promoter SV40 T-antigen transgenic mouse.Hypertension 17:1167–1172

114. Sigmund CD, Jones CA, Jacob HJ, Ingelfinger J, Kim U,Gamble D, Dzau VJ, Gross KW (1991) Pathophysiology ofvascular smooth muscle in renin promoter-T-antigen trans-genic mice. Am J Physiol 260:F249–F257

115. Sigmund CD, Jones CA, Fabian JR, Mullins JJ, Gross KW(1990) Tissue and cell specific expression of a renin promot-er-reporter gene construct in transgenic mice. Biochem Bio-phys Res Commun 170:344–350

116. Sigmund CD, Jones CA, Mullins JJ, Kim U, Gross KW(1990) Expression of murine renin genes in subcutaneousconnective tissue. Proc Natl Acad Sci USA 87:7993–7997

117. Sola C, Tronik D, Dreyfus M, Babinet C, Rougeon F (1989)Renin-promoter SV40 large T-antigen transgenes induce tu-mors irrespective of normal cellular expression of reningenes. Oncogene Res 5:149–153

118. Miller CCJ, Carter AT, Brooks JI, Lovell-Badge RH, Bram-mar WJ (1989) Differential extra-renal expression of themouse renin genes. Nucleic Acids Res 17:3117–3128

119. Fukamizu A, Seo MS, Hatae T, Yokoyama M, Nomura T,Katsuki M, Murakami K (1989) Tissue-specific expression ofthe human renin gene in transgenic mice. Biochem BiophysRes Commun 165:826–832

120. Sigmund CD, Jones CA, Kane CM, Wu C, Lang JA, GrossKW (1992) Regulated tissue- and cell-specific expression ofthe human renin gene in transgenic mice. Circ Res 70:1070–1079

138

136. Di Nicolantonio R, Lan L, Wilks A (1998) Nucleotide varia-tions in intron 1 of the renin gene of the spontaneously hy-pertensive rat. Clin Exp Hypertens 20:27–40

137. Germain S, Bonnet F, Fuchs S, Philippe J, Corvol P, Pinet F(1999) Dissection of silencer elements in first intron control-ling the human renin gene. J Hypertens 17:899–905

138. Yu H, Di Nicolantonio R (1998) Altered nuclear proteinbinding to the first intron of the renin gene of the spontane-ously hypertensive rat. Clin Exp Hypertens 20:817–832

139. Voigtländer T, Ganten D, Bader M (1999) Transcriptionalregulation of the rat renin gene by regulatory elements in in-tron I. Hypertension 333:303–311

140. Lang JA, Ying L-H, Morris BJ, Sigmund CD (1996) Tran-scriptional and posttranscriptional mechanisms regulate hu-man renin gene expression in Calu-6 cells. Am J Physiol271:F94–F100

141. Lee-Kirsch MA, Gaudet F, Cardoso MC, Lindpaintner K(1999) Distinct renin isoforms generated by tissue-specifictranscription initiation and alternative splicing. Circ Res84:240–246

142. Clausmeyer S, Stürzebecher R, Peters J (1999) An alternativetranscript of the rat renin gene can result in a truncated prore-nin that is transported into adrenal mitochondria. Circ Res84:337–344

143. Peters J, Obermuller N, Woyth A, Peters B, Maser Gluth C,Kranzlin B, Gretz N (1999) Losartan and angiotensin II in-hibit aldosterone production in anephric rats via different ac-tions on the intraadrenal renin-angiotensin system. Endocri-nology 140:675–682

144. Chen M, Schnermann J, Smart AM, Brosius FC, Killen PD,Briggs JP (1993) Cyclic AMP selectively increases reninmRNA stability in cultured juxtaglomerular granular cells. JBiol Chem 268:24138–24144

145. Sinn PL, Sigmund CD (1999) Human renin mRNA stabilityis increased in response to cAMP in Calu-6 cells. Hyperten-sion 33:900–905

146. Tillmann-Bogush M, Heaton JH, Gelehrter TD (1999) Cyclicnucleotide regulation of PAI-1 mRNA stability – identifica-tion of cytosolic proteins that interact with an A-rich se-quence. J Biol Chem 274:1172–1179

147. Stec DE, Sigmund CD (1998) Modifiable gene expression inmice: kidney-specific deletion of a target gene via the cre-loxP system. Exp Nephrol 6:568–575

148. Davisson RL, Ding Y, Stec DE, Catterall JF, Sigmund CD(1999) Novel mechanism of hypertension revealed by cell-specific targeting of human angiotensinogen in transgenicmice. Physiol Genomics 1:3–9

149. Schinke M, Baltatu O, Böhm M, Peters J, Rascher W, BriccaG, Lippoldt A, Ganten D, Bader M (1999) Blood pressure re-duction and diabetes insipidus in transgenic rats deficient inbrain angiotensinogen. Proc Natl Acad Sci USA 96:3975–3980

150. Bader M, Kang N, Walther T, Fukamizu A, Murakami K,Ganten D (1996) Phenotypic rescue of angiotensinogen-knock-out mice by tissue-specific expression of a rat angio-tensinogen transgene (abstract). Hypertension 28:708

139

121. Thompson MW, Smith SB, Sigmund CD (1996) Regulationof human renin mRNA expression and protein release intransgenic mice. Hypertension 28:290–296

122. Yan Y, Chen R, Pitarresi T, Sigmund CD, Gross KW, SealeyJE, Laragh JH, Catanzaro DF (1998) Kidney is the onlysource of human plasma renin in 45-kb human renin trans-genic mice. Circ Res 83:1279–1288

123. Sinn PL, Zhang X, Sigmund CD (1999) JG cell expressionand partial regulation of a human renin genomic transgenedriven by a minimal renin promoter. Am J Physiol 277:F634–F642

124. Ganten D, Wagner J, Zeh K, Bader M, Michel J-B, Paul M,Zimmermann F, Ruf P, Hilgenfeldt U, Ganten U, Kaling M,Bachmann S, Fukamizu A, Mullins JJ, Murakami K (1992)Species specificity of renin kinetics in transgenic rats harbor-ing the human renin and angiotensinogen genes. Proc NatlAcad Sci USA 89:7806–7810

125. Bohlender J, Fukamizu A, Lippoldt A, Nomura T, Dietz R,Menard J, Murakami K, Luft FC, Ganten D (1997) High hu-man renin hypertension in transgenic rats. Hypertension29:428–434

126. Yan Y, Hu L, Chen R, Sealey JE, Laragh JH, Catanzaro DF(1998) Appropriate regulation of human renin gene expres-sion and secretion in 45-kb human renin transgenic mice. Hy-pertension 32:205–214

127. Catanzaro DF, Chen R, Yan Y, Hu LF, Sealey JE, Laragh JH(1999) Appropriate regulation of renin and blood pressure in45-kb human renin/human angiotensinogen transgenic mice.Hypertension 33:318–322

128. Sinn PL, Davis DR, Sigmund CD (1999) Highly regulatedcell type-restricted expression of human renin in mice con-taining 140-or 160-kilobase pair P1 phage artificial chromo-some transgenes. J Biol Chem 274:35785–35793

129. Fukamizu A, Sugimura K, Takimoto E, Sugiyama F, Seo MS,Takahashi S, Hatae T, Kajiwara N, Yagami K, Murakami K(1993) Chimeric renin angiotensin system demonstrates sus-tained increase in blood pressure of transgenic mice carryingboth human renin and human angiotensinogen genes. J BiolChem 268:11617–11621

130. Merrill DC, Thompson MW, Carney CL, Granwehr BP,Schlager G, Robillard JE, Sigmund CD (1996) Chronic hy-pertension and altered baroreflex responses in transgenicmice containing the human renin and human angiotensinogengenes. J Clin Invest 97:1047–1055

131. Yan Y, Jones CA, Sigmund CD, Gross KW, Catanzaro DF(1997) Conserved enhancer elements in human and mouserenin genes have different transcriptional effects in AS4.1cells. Circ Res 81:558–566

132. Shi Q, Black TA, Gross KW, Sigmund CD (1999) Species-specific differences in positive and negative regulatory ele-ments in the renin gene enhancer. Circ Res 85:479–488

133. Germain S, Bonnet F, Philippe J, Fuchs S, Corvol P, Pinet F(1998) A novel distal enhancer confers chorionic expressionon the human renin gene. J Biol Chem 273:25292–25300

134. Smith DL, Morris BJ (1991) Transient expression analyses ofDNA extending 2.4 kb upstream of the human renin gene.Mol Cell Endocrinol 80:139–146

135. Voigtländer T, Ripperger A, Ganten D, Bader M (1995) Tran-scriptional silencer in intron I of the rat renin gene. Adv ExpMed Biol 377:285–292