TY - JOUR
T1 - Characterization of VAMP isoforms in 3T3-L1 adipocytes
T2 - implications for GLUT4 trafficking
AU - Sadler, Jessica B.A.
AU - Bryant, Nia J.
AU - Gould, Gwyn W.
PY - 2015/2/1
Y1 - 2015/2/1
N2 - The fusion of GLUT4-containing vesicles with the plasma membrane of adipocytes is a key facet of insulin action. This process is mediated by the formation of functional soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) complexes between the plasma membrane t-SNARE complex and the vesicle v-SNARE or VAMP. The t-SNARE complex consists of Syntaxin4 and SNAP23, and whereas many studies identify VAMP2 as the v-SNARE, others suggest that either VAMP3 or VAMP8 may also fulfil this role. Here we characterized the levels of expression, distribution, and association of all the VAMPs expressed in 3T3-L1 adipocytes to provide the first systematic analysis of all members of this protein family for any cell type. Despite our finding that all VAMP isoforms form SDS-resistant SNARE complexes with Syntaxin4/SNAP23 in vitro, a combination of levels of expression (which vary by >30-fold), subcellular distribution, and coimmunoprecipitation analyses lead us to propose that VAMP2 is the major v-SNARE involved in GLUT4 trafficking to the surface of 3T3-L1 adipocytes.
AB - The fusion of GLUT4-containing vesicles with the plasma membrane of adipocytes is a key facet of insulin action. This process is mediated by the formation of functional soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) complexes between the plasma membrane t-SNARE complex and the vesicle v-SNARE or VAMP. The t-SNARE complex consists of Syntaxin4 and SNAP23, and whereas many studies identify VAMP2 as the v-SNARE, others suggest that either VAMP3 or VAMP8 may also fulfil this role. Here we characterized the levels of expression, distribution, and association of all the VAMPs expressed in 3T3-L1 adipocytes to provide the first systematic analysis of all members of this protein family for any cell type. Despite our finding that all VAMP isoforms form SDS-resistant SNARE complexes with Syntaxin4/SNAP23 in vitro, a combination of levels of expression (which vary by >30-fold), subcellular distribution, and coimmunoprecipitation analyses lead us to propose that VAMP2 is the major v-SNARE involved in GLUT4 trafficking to the surface of 3T3-L1 adipocytes.
KW - vamp isoforms
KW - 3T3-L1 adipocytes
KW - GLUT4 trafficking
UR - http://www.scopus.com/inward/record.url?scp=84921830579&partnerID=8YFLogxK
U2 - 10.1091/mbc.E14-09-1368
DO - 10.1091/mbc.E14-09-1368
M3 - Article
C2 - 25501368
AN - SCOPUS:84921830579
VL - 26
SP - 530
EP - 536
JO - Molecular Biology of the Cell
JF - Molecular Biology of the Cell
SN - 1059-1524
IS - 3
ER -
