Table 1.

Physiological regulation of GSC lineages by diet-dependent pathways

Pathway	Organism	Role
AMPK	C. elegans	Inhibits germline proliferation during larval starvation (Fukuyama et al. 2012; Narbonne and Roy 2006b)
	Drosophila	Inhibits follicle cell growth in the ovary (Haack et al. 2013)
	mouse	Sertoli cell LKB1 promotes SSC proliferation and maintenance (Tanwar et al. 2012)
TOR	C. elegans	Promotes larval progenitor proliferation (Korta et al. 2012)
	Drosophila	Levels control GSC maintenance and proliferation (LaFever et al. 2010; Sun et al. 2010) and germline cyst survival (LaFever et al. 2010) in the ovary
		Regulates ovarian cyst growth intrinsically and via follicle cells (LaFever et al. 2010; Sun et al.)
	A. aegypti	Elevated in ovary following blood meal (Hansen et al. 2005; Roy and Raikhel 2012)
		Required in the fat body for vitellogenesis (Hansen et al. 2004; Hansen et al. 2005; Roy and Raikhel 2012, 2011; Carpenter et al. 2012)
	mouse (mTOR)	Promotes germline proliferation and meiosis during development (Busada et al. 2015)
		Global hyperactivation inhibits SSC maintenance (Hobbs et al. 2010)
		Overactivation in Sertoli cells leads to intrinsic polarity defects, reduced SSC proliferation, and SSC loss (Tanwar et al. 2012)
Insulin	C. elegans	Promotes PGC proliferation (Michaelson et al. 2010)
	Drosophila	Promotes ovarian GSC proliferation, cyst growth, and vitellogenesis (LaFever and Drummond-Barbosa 2005)
		Controls ovarian GSC maintenance via cap cells (Hsu and Drummond-Barbosa 2009)
		Promotes GSC proliferation and maintenance in testis (Roth et al. 2012; McLeod et al. 2010)
	A. aegypti	Required for progression through vitellogenesis (reviewed in Attardo et al. 2005)
	mouse	Global requirement for InR and Igf1r for testicular development (Pitetti et al. 2013a)
		InR and Igf1r promote developmental Sertoli cell proliferation (Pitetti et al. 2013b)
		Global IRS2 mice have small testes and progressive germ cell loss as adults (Griffeth et al. 2013)
		Global Igf1 mice have reduced spermatogenesis (Baker et al. 1996)
Ecdysone	Drosophila	Promotes ovarian GSC maintenance, proliferation (Ables and Drummond- Barbosa 2010), and vitellogenesis (Buszczak et al. 1999)
		Required in escort cells for germline differentiation (Konig et al. 2011; Morris and Spradling 2012)
		Required in CySCs for GSC maintenance and progeny survival in the testis (Li et al. 2014)
	A. aegypti	After a blood meal, ecdysone response genes expressed in ovary (Pierceall et al. 1999)
		Required in the fat body for vitellogenesisa (Martin et al. 2001)
Retinoic acid	mouse	Germ cell RARα and Sertoli cell RARγ are together required for meiosis (Gely-Pernot et al. 2015)
		Required in Sertoli cells for germ cell meiosis (Tong et al. 2013; Raverdeau et al. 2012)
Androgen receptor	mouse	Required in Sertoli cells for cell survival and meiosis (Abel et al. 2008; Hobbs et al. 2010; De Gendt et al. 2004)
		Required intrinsically by PTMs for normal sperm counts (Zhang et al. 2006)
AdipoR	C. elegans	Global mutation reduces brood size (Svensson et al. 2011)
	Drosophila	Required for ovarian GSC maintenance (Laws et al. 2015)
	mouse	AdipoR2 global mutants are aspermic (Bjursell et al. 2007)
Leptin	Drosophila	Required in fat body to promote ILP secretion from the brain (Rajan and Perrimon 2012)
	mouse	Promotes fertility (Mounzih et al. 1997) and germ cell survival (Bhat et al. 2006)