presentation by jennifer unterbrink pcdu seminar november 11th, 2015

presentation by Jennifer UnterbrinkPCDU seminar

November 11th, 2015

ESCRT Complex and Retromer

Endosomes in plants

Endosomes in plants

www.illuminatedcell.com

Endosomes in plants heterogenous collection of organelles

function:

sorting and delivery from the cell surface

transport from TGN to lysosome/ vacuole

biosynthetic AND endocytotic pathway

Multivesicular bodies

Winter and Hauser, 2006. Trends in Plant Sc. Vol.11 No.3

Endosomal trafficking

retrograde transportanterograde transport

biosynthetical/ secretory transportBruce Alberts (Ed.), Molecular biology of the cell

ER

Golgi

EE

secretory vesicles

PM

LE

V/ L

Coats of the late endosomal system

Retromer schematic

Schellmann and Pimpl, 2009: Curr. Opinion in Plant Biol. 12

SNX: phox-homology domain, allows association with phospholipids (PI3P)

BAR domain

Bin-Amphiphysin-Rvs

Retromer structure

SNXs important for Retromer function

Rojas et al., 2007. Mol. and Cell. Biol. 02/2007

Plant Retromer

Schellmann and Pimpl, 2009: Curr. Opinion in Plant Biol. 12

ESCRTs

ESCRT subunits in plants

Schellmann and Pimpl, 2009: Curr. Opinion in Plant Biol. 12

ESCRT subunits in plants

Schellmann and Pimpl, 2009: Curr. Opinion in Plant Biol. 12

ESCRTs in cytokinesis

Spitzer et al., 2006. Development 133

The coat to perdition

www.nature.com, 2015/11/08

ESCRT-dependent protein sorting

Winter and Hauser, 2006. Trends in Plant Sc. 11

Ubiquitin

www.nobelprize.org/nobel_prizes/chemistry/laureates/2004/chempub1high.jpg

ESCRT-dependent vesicle formation

Cai et al., 2014. Plant Physiol. Vol.165 No.3c

Figure 7.Immunogold detection of VSRs in wild-type and transgenic Arabidopsis plants with induced expression of ESCRT-III mutants. Six-day-old wild-type plants (A and B) and transgenic plants (C–J) germinated and cultured in the absence of inducers were transferred onto medium containing 10 μM β-estradiol for 24 h to induce the expression of VPS20.1-1-112-YFP (C and D), SNF7.1(L22W)-YFP (E and F), VPS24.1-1-152-YFP (G and H), or VPS2.1-1-179-YFP (I and J). Arabidopsis roots were subjected to high-pressure frozen/freeze substitution followed by ultrathin sectioning and immunogold labeling using VSR antibodies. Bar = 100 nm.

FREE1

peripheral membrane-associated protein

Gao et al., 2014. Curr. Biol. 24

binds to PI3P via the FYVE domain

FYVE domainFYVE zinc finger domainnamed after the Cys-rich proteins Fab1, YOTB, Vac1, EEA1

binds PI3P

is composed of two small β-hairpins (zinc knuckles)followed by a α-helix

FYVE finger binds to two Zn-ions

FREE1 function

transposon insertion in A.thaliana

Gao et al., 2014. Curr. Biol. 24

homozygous free1 mutants are not viable

expression of GFP-tagged FREE1 rescued the seedling lethality

FREE1 function

Gao et al., 2014. Curr. Biol. 24

https://www.youtube.com/watch?v=_4DM48ZPR0A