Ad hoc Seminar – Ryusuke Niwa
“Neuroendocrine control of germline stem cell proliferation and energy homeostasis in the fruit fly Drosophila melanogaster”
Communication between different organs is essential for responding to environmental cues or changes in the physiological status of an organism. Recent studies have revealed the existence of humoral factors or hormones, which are transported by the circulatory system to different organs and achieve coordination between them. However, the underlying mechanisms have not been extensively explored.
To investigate how interorgan communication contributes to the regulation of various biological phenomena, the fruit fly Drosophila melanogaster serves as an excellent model system. We have previously found that the peptide hormone Neuropeptide F (NPF) is released from the midgut enteroendocrine cells (EECs) and then received in the ovary to positively regulate proliferation of female germline stem cells (GSCs) [Ameku & Niwa. PLOS Genetics 2016; Ameku et al. PLOS Biology 2018]. This study suggests an essential interaction between the digestive system and the ovary, which regulates the size of stem cell populations.
In this presentation, I am presenting 2 of our recent findings regarding interorgan communications in Drosophila. First, we report that mating-induced GSC proliferation in female Drosophila is regulated by some monoaminergic neurons in the ventral nerve cord, which directly project to the ovary. Second, we identify the NPF-positive EECs in the adult midgut as nutrient-sensing cells that control an insulin counter-regulatory hormone, resulting in affecting fat storage and energy homeostasis. Our findings would further extend the importance of organ-organ interactions in the systematic regulation of biological systems.
University of Tsukuba & AMED, Japan