![]()
|
|
||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Papers In Press, published online ahead of print December 29, 2005
Dept. of Biology, Kansas State University, Manhattan, Kansas 66506
Corresponding Author: mora{at}ksu.edu
Adiponectin (Acrp30) is an insulin-sensitizing hormone produced and secreted exclusively by adipose tissue. Confocal fluorescent microscopy demonstrated the colocalization of adiponectin with the Golgi membrane markers p115,-COP and the trans-Golgi Network marker, Syntaxin 6. Treatment of cells with Brefeldin A redistributed adiponectin to the endoplasmic reticulum where it colocalized with the chaperone protein BIP and inhibited secretion of adiponectin demonstrating a requirement for a functional Golgi apparatus for adiponectin release. Confocal fluorescent microscopy also demonstrated a colocalization of endogenous adiponectin with that of expressed GGA1myc (Golgi-localizing -adaptin ear homology ARF binding protein), but with no significant overlap between adiponectin and the GGA2myc or GGA3myc isoforms. Consistent with confocal fluorescent microscopy, transmission electron microscopy demonstrated the colocalization of GGA1 with adiponectin. Although GGA1 did not directly interact with the adiponectin protein, adipocytes adiponectin enriched membrane compartments were precipitated by a GST-GGA1 cargo binding domain (VHS) fusion protein but not with a GST-GGA2 VHS or GST-GGA3 VHS fusion proteins. Moreover, co-expression of adiponectin with a GGA1 dominant interfering mutant (GGA1-VHS GAT domain) resulted in a marked inhibition of adiponectin secretion in both 3T3L1 adipocytes and HEK293 cells, whereas no inhibition was detected with the truncated mutants GGA2-VHSGAT or GGA3-VHSGAT. Moreover, co-expression of wild type GGA1 with adiponectin enhanced secretion of adiponectin. Interestingly, leptin secretion was unaffected by neither the wild type form or GGA1 nutant. Taken together these data demonstrate that the trafficking of adiponectin through its secretory pathway is dependent on GGA coated vesicles.
J. Biol. Chem, 10.1074/jbc.M511313200
Submitted on October 18, 2005
Revised on November 28, 2005
Accepted on December 29, 2005
Intracellular trafficking and secretion of adiponectin is dependent on GGA coated vesicles
![]()
CiteULike
Complore
Connotea
Del.icio.us
Digg
Reddit
Technorati What's this?
This article has been cited by other articles:
![]() |
M. Itoh, T. Suganami, N. Satoh, K. Tanimoto-Koyama, X. Yuan, M. Tanaka, H. Kawano, T. Yano, S. Aoe, M. Takeya, et al. Increased Adiponectin Secretion by Highly Purified Eicosapentaenoic Acid in Rodent Models of Obesity and Human Obese Subjects Arterioscler. Thromb. Vasc. Biol., September 1, 2007; 27(9): 1918 - 1925. [Abstract] [Full Text] [PDF] |
||||
![]() |
X. Chen, B. M. Sebastian, and L. E. Nagy Chronic ethanol feeding to rats decreases adiponectin secretion by subcutaneous adipocytes Am J Physiol Endocrinol Metab, February 1, 2007; 292(2): E621 - E628. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. Williams, S. W. Hicks, C. E. Machamer, and J. E. Pessin Golgin-160 Is Required for the Golgi Membrane Sorting of the Insulin-responsive Glucose Transporter GLUT4 in Adipocytes Mol. Biol. Cell, December 1, 2006; 17(12): 5346 - 5355. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
| All ASBMB Journals | Molecular and Cellular Proteomics |
| Journal of Lipid Research | ASBMB Today |