PgmNr W4012: Maternal diet influences intergenerational phenotypic plasticity affecting progeny size and starvation resistance.

Authors:
Jonathan Hibshman; Anthony Hung; Ryan Baugh


Institutes
Duke University, Durham, NC.


Keyword: Gametogenesis, Fertilization, Egg-embryo transition

Abstract:

Dietary restriction (DR) delays aging but reduces fertility. We demonstrate maternal effects of DR in the roundworm C. elegans, suggesting physiological regulation of maternal provisioning. Compared to being fed ad libitum (AL), worms cultured under DR are smaller, delay reproduction, and produce fewer but larger progeny. Furthermore, progeny of DR worms are buffered from advearse consequences of early-larval starvation: They grow faster and are more fertile than control progeny following extended starvation, suggesting a fitness advantage. Nutrient availability is assessed during oogenesis, in late larvae and young adults, rather than affecting a set point in young larvae. Insulin-like signaling mediates effects of nutrient availability on progeny size. Reduced signaling through the insulin-like receptor daf-2/InsR in the soma causes constitutively large progeny, and its effector daf-16/FoxO is required for this effect. Additional regulators of energy homeostasis including the nuclear hormone receptor nhr-49/Hnf4, pha-4/FoxA, and skn-1/Nrf are also required for progeny size plasticity in response to diet. Disruption of daf-2/InsR does not require nhr-49/Hnf4, pha-4/FoxA, or skn-1/Nrf for increased embryo size, suggesting they act upstream or in parallel to insulin-like signaling. This work presents an invertebrate model for maternal effects of DR, demonstrates potentially adaptive intergenerational phenotypic plasticity, and identifies conserved pathways mediating these effects.



Wormbase Genetic Index
1. daf-2
2. daf-16
3. nhr-49
4. skn-1
5. pha-4