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Angela SanchezMentor: Pamela Larsen

Mechanisms of LongevityGene by Environment Interactions

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How can we live a long healthy life?23-26% of longevity is geneticRemaining 75% is environmentalHerskind 1996

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How can I live a long healthy life? GENETICS

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Environmental influences on aging and longevity

Sun exposureSmokingAlcoholBMIDivorceGuyuron 2009Christensen 2009

We know what associates with shorter life. What if your normal not tanning bed mom what if you dont smoke you use spf you drink in moderation you are not obese, so thats what we want to know.3

We must understand each component G, E, and GxE

Whats the probability that you will live a long healthy life?

What can we do to maximize our longevity potential?Life span is a complex traitPhenotype = G + E + (G x E)

We want to understand the molecular mechanism and understand GxE in a way that is predictive.4

Qa

Genetic and environmental manipulations that alter lifespanTemperaturedaf-2 Identify mechanisms of aging and longevity by systematic analysisEnvironmental Genetic

MAKE GRAPHS CONSISTENT5

Qa

Further rationale for genotype selectiondaf-2 25CWild type 25C

daf-2 15CWild type 15C

Homologous to human insulin/IGF receptorPhenocopies aspects of cool temperatureAbnormal response to different cultivation temperatures

Larsen et al 1995 Gems et al 1998

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Lifespan of independent daf-2 alleles all missense

daf-2 involved in acclimatization to temperatureunlike daf-2, temperature response is daf-16 independent

Animate so slopes show first7

TEMPERATURE REGULATIONdaf-2 REGULATONWTWT15C25Cdaf-2daf-215C25Cvsvsvsvs

Microarray comparisons: daf-2 and temperature

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TEMPERATURE REGULATIONdaf-2 Wild type ++15C25C

15C25Cvsvsvsvs

Microarray comparisons: daf-2 and temperature e1370m41m596m577m579e1370m41m596m577m579daf-2 REGULATION

For all we know I am m577 you are m41 and so and so is e1370 and 596 is whoever (how many variants 14 IGF1 snps and 16 in IGF1 binding protein. NIH hapmap SNPs look at this9

QaNumber of Temperature Regulated Genes(Curtis, Tavare, Takano S. Larsen P. et al.)700 shared between all daf-2 mutants

WTWT15C25Cdaf-2daf-215C25C

1000

2000

3000

4000HIGHER at 25CLOWER at 25C

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QaQaNumber of daf-2 regulated genes(Curtis, Tavare, Takano S. Larsen P. et al.)

WT15Cdaf-215CWT25Cdaf-225C

m41 m577 e1370 m596 m579 m41 m577 e1370 m596 m579 HIGHERLOWER200

400

6002000

4000

6000

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Types of regulated genes(Curtis, Tavare, Takano S. Larsen P. et al.)Protein synthesisLysosomal proteasesER resident proteins

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HYPOTHESIS

Proteostasis is a key mechanismfor healthy long-term survival

SIGNIFICANCEEnvironmental changes trigger beneficial and detrimental responses. By associating molecular signatures with life expectancy we can predict phenotypic outcome in different genotypes and environments.

Cool core temperature genotype response not universal phenotype outcome. Genetically complex trait of healthy long-term survival. 13

Specific Aim 1Determine whether genes that are lowered at 25C in all genotypes cause longevity or aging .Validate by qPCRDetermine if organelle structures are altered by temperatureDetermine the effect of RNAi of selected genes at 15C and 25C on life span

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QaIs lysosome structure or number altered by elevated temperature?

25C 15C

DAY 1MRLT

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QaIs lysosome structure or number altered by elevated temperature?

25C 15C DAY 1MRLT

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QaIs lysosome structure or number altered by elevated temperature?

25C 15C DAY 1MRLT

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Specific Aim 1Validate by qPCRDetermine if organelle structures are altered by temperatureDetermine the effect of RNAi of selected genes at 15C and 25C on life span

Determine whether genes that are lowered at 25C in all genotypes cause longevity or aging .

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Effect of lysosomal inhibitors on lifespan

Temperature dependent phenotype of proteostasis inhibition15C25Cn=75p= 0.0028*n=64p=