2006 Fiscal Year Final Research Report Summary

Identification and characterization of active glucose transport membrane domain in adipocytes

Research Project

Project/Area Number	17590934
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Single-year Grants
Section	一般
Research Field	Metabolomics
Research Institution	Yamaguchi University
Principal Investigator	EMOTO Masahiro Yamaguchi University, Hospital, research associate, 医学部附属病院, 助手 (50294640)
Co-Investigator(Kenkyū-buntansha)	TSURU Masatoshi Yamaguchi University, Hospital, research associate, 医学部附属病院, 助手 (20379960)
Project Period (FY)	2005 – 2006
Keywords	membrane microdomain / insulin / glucose transporter / actin / molecular motors / GPI anchored proteins
Research Abstract	We determined the active microdomains for glucose-transport "Hot-spots" in adipocytes. These areas are well actin-reorganized membranes and activated by insulin. We found two independent proteins ; Rmel and GPI anchored protein p69, as regulators of glucose transport activity. Rmel inhibits GLUT4 entry into caveolin rafts; in contrast, p69 promotes it. These data suggests that membrane microdomains are important for glucose homeostasis. Furthermore, we identified IRS1 foci just beneath the "hot-spots" area, where insulin signaling are inhibited by signal cross-talk with TNF alpha. This micro-structures are also functional for normal regulation for glucose metabolism. These results suggest that membrane microdomains/ microstructures are functional organization for normal glucose metabolism.