Department of Physiology Zoom seminar TODAY, Tuesday, June 9, at 3:30PM

Dr. Demarco will present a Zoom seminar entitled “Metabolic regulation of the male germline stem cell niche in Drosophilia” TODAY, Tuesday, June 9, 2020, from 3:30-4:30 pm. Zoom call-in particulars are included below. PLEASE NOTE: This is a password-protected login.

Dr. Demarco received his Ph.D. in Cell, Molecular, and Developmental Biology from the University of Kansas. He then continued into postdoctoral work in the laboratory of Dr. Leanne Jones (first at the Salk Institute in San Diego and now at UCLA). In Dr. Jones laboratory, Dr. Demarco started to study how mitochondrial dynamics and metabolism impact stem cell behavior, using the male germline stem cell niche in Drosophilia melanogaster as a model.

Abstract: The capacity of stem cells to self-renew or differentiate has been attributed to distinct metabolic states. A genetic screen targeting regulators of mitochondrial dynamics revealed that mitochondrial fusion is required for male germline stem cell (GSC) maintenance in Drosophilia melanogaster. Depletion of Mitofusin (dMfn) or Optic atrophy 1 (OPA1) led to dysfunctional mitochondria, activation of Target of Rapamycin (TOR), and a dramatic accumulation of lipid droplets. Enhancement of lipid utilization by the mitochondria attenuated TOR activation and rescued GSC loss caused by inhibition of mitochondrial fusion. Moreover, constitutive activation of the TOR-pathway target and lipogenesis factor Sterol regulation element binding protein (SREBP) also resulted in GSC loss, whereas inhibition of SREBP rescued GSC loss triggered by depletion of dMfn. My findings highlight a critical role for mitochondrial fusion and lipid homeostasis in GSC maintenance, providing insight into the potential impact of mitochondrial and metabolic diseases on stem and/or germ cell fusion.

We look forward to seeing everyone this afternoon!