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Day Date Subject To be read prior to this class period: Th 3/12 Chapter 7T 3/17 students = epigenetics RichieTh 3/19 students = toxicology and cancer Anna, Bouradee T 3/24 Th 3/26T 3/31 no class - Spring BreakTh 4/2 no class - Spring BreakT 4/7 students = life cyclesTh 4/9 Chapter 9second short writing assignment due at the start of class on Thurs, 4/9T 4/14 students = nutrients and development Meg, ZebTh 4/16 T 4/21 students = evolution GregTh 4/23 Chapter 10T 4/28Th 4/30 Capstone Papers due Chapter 8T 5/5 Discussion of Capstone PapersTh 5/7 Chapter 8

Comprehensive Final Exam, Thursday, May 7th, 8:00 – 10:00 AM 

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second short writing assignment for your Capstone project:

1)Describe your career goals.2)Describe you past, current, and future career plans and efforts.3) Explain which college course has had the most impact on yourcareer plans and why (not this class). 4) Connect your career goals, plans, and efforts with your Capstone project efforts in as many ways as you can. These can be similaritiesand/or differences.5) What kind of sources/references could be include in this writing?Incorporate at least five sources/references.

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toxicology and cancer

epigenetics

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epigenetics (narrow definition) = DNA methylation and/or histone modification

DNA methylation stories:

1) promoter of the glucocorticoid receptor

2) thrifty phenotype in mammmals

3) folic acid (methyl donor) in obesity of agouti rats

4) queen ants

5) transgenerational

6) Richie’s paper on the “methylome” imprinting embryonic stem cells

In the promoter for the glucocorticoid receptor

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I Googled:

glucocorticoid receptor DNA methylation brain

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epigenetics (narrow definition) = DNA methylation and/or histone modification

DNA methylation stories:

1) promoter of the glucocorticoid receptor

2) thrify phenotype in mammmals

3) folic acid (methyl donor) in obesity of agouti rats

4) queen ants

5) transgenerational

6) Richie’s paper on the “methylome” imprinting embryonic stem cells

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There are many examples of maladaptive responses in Chapter 7 plus new examples that aren’t maladaptive.maladaptive = a misinterpretation of the environment

Dutch Hunger Winter

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There are many examples of maladaptive responses in Chapter 7 plus new examples that aren’t maladaptive.maladaptive = a misinterpretation of the environment

Dutch Hunger Winter

The thrifty phenotype hypothesis is a example of a Predictive Adaptive Response.

All the examples from the first third of the course were PARs.

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There are many examples of maladaptive responses in Chapter 7 plus new examples that aren’t maladaptive.maladaptive = a misinterpretation of the environment

Dutch Hunger Winter

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correlation of adult blood pressure and birth rate:

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Molecular mechanism might be in the kidney?

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thrifty phenotype in mammals

KIDNEY:Poor nutrition during fetal life reduces the number of nephrons predisposing the person to high blood pressure later in life.

PANCREAS:Poor nutrition during fetal life reduces the number of insulin-secreting cells predisposing the person to type 2 diabetes later in life.

LIVER:Poor nutrition during fetal life changes histology and gene expression of the liver. One result is that more glucose is made and less is degraded.

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Thrifty Phenotype Hypothesis: Malnourished fetuses are “programmed” to expect poor nutrients postnatally and set their biochemical parameters to conserve energy and store fat.

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Thrifty Phenotype Hypothesis: Malnourished fetuses are “programmed” to expect poor nutrients postnatally and set their biochemical parameters to conserve energy and store fat.

The thrifty phenotype appears to be triggered by either poor nutrients or stress. (???)

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epigenetics (narrow definition) = DNA methylation and/or histone modification

DNA methylation stories:

1) promoter of the glucocorticoid receptor

2) thrifty phenotype in mammmals

3) folic acid (methyl donor) in obesity of agouti rats

4) queen ants

5) transgenerational

6) Richie’s paper on the “methylome” imprinting embryonic stem cells

Environment can affect phenotype.Environment = nutrients = folic acid (a methyl donor)Phenotype = fur color and obesity Plasticity caused by = methylation patterns of the agouti gene

Reaction Norm

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epigenetics (narrow definition) = DNA methylation and/or histone modification

DNA methylation stories:

1) promoter of the glucocorticoid receptor

2) thrifty phenotype in mammmals

3) folic acid (methyl donor) in obesity of agouti rats

4) queen ants

5) transgenerational

6) Richie’s paper on the “methylome” imprinting embryonic stem cells

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The environment (nutrients in the form of ‘royal jelly’) acts to increase hormones (juvenile hormone + insulin signaling) and their effects include decreased DNA methylation, which increases expression of genes needed to form queens.

EXPERIMENT:

When fed methylation inhibitors, larvae develop into queens.

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epigenetics (narrow definition) = DNA methylation and/or histone modification

DNA methylation stories:

1) promoter of the glucocorticoid receptor

2) thrifty phenotype in mammmals

3) folic acid (methyl donor) in obesity of agouti rats

4) queen ants

5) transgenerational

6) Richie’s paper on the “methylome” imprinting embryonic stem cells

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Definition from Genetics:

allele = one version of a gene.

chromatin = DNA plus associated proteins. Chromosomes are composed of chromatin.

Looking ahead to Chapter 10:

Altered chromatin can be inherited and is called an epiallele.

Pregnant rats fed a low-protein diet have offspringpredisposed to obesity. In Chapter 7, thereare changes in DNA methylation on the PPARalpha and Dnmt1 genes (involved in fat production).

Transgenerational

Multigenerational

We have had examples of maladaptive responses that involve DNA methylation:

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epigenetics (narrow definition) = DNA methylation and/or histone modification

DNA methylation stories:

1) promoter of the glucocorticoid receptor

2) thrifty phenotype in mammmals

3) folic acid (methyl donor) in obesity of agouti rats

4) queen ants

5) transgenerational

6) Richie’s paper on the “methylome” imprinting embryonic stem cells

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research article Richie selected

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11.5 germ cell migration

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In primordial germ cells (PGCs) representing the precursorsof SSCs and all other germ cells, the genome is demethylatedand, in particular, the genomic imprints, i.e. the parent-specific methylationmarks of imprinted genes, of the previous generation are erasedfrom the grandparental chromosomes (with respect to the newembryo). In the mouse, this wave of genome-wide epigenetic reprogrammingstarts between day 10.5 post conceptionem (p.c.) beforemigration of PGCs into the genital ridge and is completed by day 13.5p.c. (Hajkova et al., 2002; Yamazaki et al., 2003). In the male germline,the establishment of novel methylation marks for imprinted genes beginsaround day 15.5 p.c., but is finished only after birth (Davis et al., 1999,2000; Li et al., 2004). After fertilization, a second wave of genome-wideepigenetic reprogramming takes place in which the vast majority of maleand female germline-derived methylation patterns are erased again andnew somatic methylation patterns for development of the new organismare established (Mayer et al., 2000a, b). To the extent of present knowledge,imprinted genes escape this second wave and maintain theirgermline-specific methylation and parent-specific expression patternsthroughout further development (Morgan et al., 2005). Thus, imprintedgenes display a differential methylation of their parental alleles and maintenanceof genomic imprinting in both ESCs and somatic cells. In contrast,pluripotency marker genes such as Oct4 and Nanog switch froma transcriptionally active and demethylated state in ESCs to a transcriptionallyrepressed and fully methylated state in somatic cells (Okita et al.,2007; Wernig et al., 2007).

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In primordial germ cells (PGCs) representing the precursorsof SSCs and all other germ cells, the genome is demethylatedand, in particular, the genomic imprints, i.e. the parent-specific methylationmarks of imprinted genes, of the previous generation are erasedfrom the grandparental chromosomes (with respect to the newembryo).

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In primordial germ cells (PGCs) representing the precursorsof SSCs and all other germ cells, the genome is demethylatedand, in particular, the genomic imprints, i.e. the parent-specific methylationmarks of imprinted genes, of the previous generation are erasedfrom the grandparental chromosomes (with respect to the newembryo). In the mouse, this wave of genome-wide epigenetic reprogrammingstarts between day 10.5 post conceptionem (p.c.) beforemigration of PGCs into the genital ridge and is completed by day 13.5p.c. (Hajkova et al., 2002; Yamazaki et al., 2003).

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In primordial germ cells (PGCs) representing the precursorsof SSCs and all other germ cells, the genome is demethylatedand, in particular, the genomic imprints, i.e. the parent-specific methylationmarks of imprinted genes, of the previous generation are erasedfrom the grandparental chromosomes (with respect to the newembryo). In the mouse, this wave of genome-wide epigenetic reprogrammingstarts between day 10.5 post conceptionem (p.c.) beforemigration of PGCs into the genital ridge and is completed by day 13.5p.c. (Hajkova et al., 2002; Yamazaki et al., 2003). In the male germline,the establishment of novel methylation marks for imprinted genes beginsaround day 15.5 p.c., but is finished only after birth (Davis et al., 1999,2000; Li et al., 2004). After fertilization, a second wave of genome-wideepigenetic reprogramming takes place in which the vast majority of maleand female germline-derived methylation patterns are erased again andnew somatic methylation patterns for development of the new organismare established (Mayer et al., 2000a, b). To the extent of present knowledge,imprinted genes escape this second wave and maintain theirgermline-specific methylation and parent-specific expression patternsthroughout further development (Morgan et al., 2005). Thus, imprintedgenes display a differential methylation of their parental alleles and maintenanceof genomic imprinting in both ESCs and somatic cells. In contrast,pluripotency marker genes such as Oct4 and Nanog switch froma transcriptionally active and demethylated state in ESCs to a transcriptionallyrepressed and fully methylated state in somatic cells (Okita et al.,2007; Wernig et al., 2007).

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In primordial germ cells (PGCs) representing the precursorsof SSCs and all other germ cells, the genome is demethylatedand, in particular, the genomic imprints, i.e. the parent-specific methylationmarks of imprinted genes, of the previous generation are erasedfrom the grandparental chromosomes (with respect to the newembryo). In the mouse, this wave of genome-wide epigenetic reprogrammingstarts between day 10.5 post conceptionem (p.c.) beforemigration of PGCs into the genital ridge and is completed by day 13.5p.c. (Hajkova et al., 2002; Yamazaki et al., 2003). In the male germline,the establishment of novel methylation marks for imprinted genes beginsaround day 15.5 p.c., but is finished only after birth (Davis et al., 1999,2000; Li et al., 2004). After fertilization, a second wave of genome-wideepigenetic reprogramming takes place in which the vast majority of maleand female germline-derived methylation patterns are erased again andnew somatic methylation patterns for development of the new organismare established (Mayer et al., 2000a, b). To the extent of present knowledge,imprinted genes escape this second wave and maintain theirgermline-specific methylation and parent-specific expression patternsthroughout further development (Morgan et al., 2005). Thus, imprintedgenes display a differential methylation of their parental alleles and maintenanceof genomic imprinting in both ESCs and somatic cells. In contrast,pluripotency marker genes such as Oct4 and Nanog switch froma transcriptionally active and demethylated state in ESCs to a transcriptionallyrepressed and fully methylated state in somatic cells (Okita et al.,2007; Wernig et al., 2007).