Function of lipid storage droplet-1 and 2 in development of Drosophila melanogaster

ショウジョウバエlipid storage droplet-1および 2遺伝子の発生過程における機能

2019-09-25

2019-09-25

Lipid droplets comprise neutral lipids that are enclosed by a monolayer of phospholipids. The surface of a lipid droplet is decorated with several types of proteins such as structural proteins, lipid-synthesis enzymes, lipases, and membrane-trafficking proteins. Notably, Drosophila and mammals share these lipid metabolism-related genes and basic metabolism function. Perilipins are known to be involved in regulating the accessibility of lipases; e.g., mammalian adipose triglyceride lipase (ATGL) and hormone-sensitive lipase (HSL), by either recruiting these enzymes or preventing their access to lipid droplets. Perilipins regulate ATGL activation through the interaction with comparative gene identification 58 (CGI-58), which is an ATGL coactivator. Also, the role of perilipin 1 locus was identified as obesity risk factors, and perilipin 2 participates in the pathogenesis of diet-induced insulin resistance. Drosophila encodes two perilipin family member, Lsd-1/perilipin-1 and Lsd-2/perilipin-2. LSD-1 indiscriminately labels lipid droplets of varying size whereas LSD-2 localizes to smaller lipid droplets. LSD-1 exclusively locates on lipid droplets while LSD-2 presents both in the cytoplasm and on lipid droplets. However, the roles of these genes in development remain unclear. This present study, we found that LSD-1 expresses not only in wing pouch but also detection in notum of wing imaginal disc. Specific knockdown of Lsd-1 by pannir-GAL4 driver in wing disc leads to split thorax phenotype, suggesting that an essential role of Lsd-1 in development of Drosophila thorax. This role of Lsd-1 is dependent on the activity of the Drosophila c-Jun N-terminal kinase, as overexpression of basket suppresses split thorax induced by Lsd-1 knockdown. Besides these events, depletion of Lsd-1 causes an enhancement apoptosis cell death in wing notum. Moreover, we also demonstrated that knockdown of Lsd-2 led to dramatic cell death and developmental defects in the wing blade. Also, Lsd-2 knockdown-induced apoptosis cell death was shown to be mediated by dFoxO. Taken together, these data indicate Lsd-1 and Lsd-2 have main role in Drosophila development.

博士(学術)

京都工芸繊維大学

14303甲第933号

http://hdl.handle.net/10212/2543

eng

none

3

Thesis or Dissertation

Thesis