TY - JOUR
T1 - Nonneuronal expression of Rab3A
T2 - Induction during adipogenesis and association with different intracellular membranes than Rab3D
AU - Baldini, G.
AU - Scherer, P. E.
AU - Lodish, H. F.
PY - 1995/5/9
Y1 - 1995/5/9
N2 - Rab3A is a small GTP-binding protein expressed predominantly in brain and neuroendocrine cells, in which it is associated with synaptic and synaptic- like vesicles, respectively. Here we report that adult mouse fat cells and 3T3-L1 adipocytes also express Rab3A mRNA and protein. They do not express synaptophysin, an abundant protein in synaptic vesicles or synaptic-like vesicles. The amount of Rab3A mRNA and protein, like that of the highly homologous isoform Rab3D, increases severalfold during differentiation of 3T3-L1 fibroblasts into mature adipocytes. In fat cells, most Rab3D and Rab3A protein is bound to membrane, irrespective of insulin addition. Rab3A and Rab3D are localized in different subcellular compartments, since about half of the Rab3A, but none of the Rab3D, is associated with a low-density organelle(s). Rab3D and Rab3A may be involved in different pathways of regulated exocytosis in adipocytes. Moreover, in adipocytes Rab3A may define an exocytic organelle that is different from synaptic vesicles or synaptic- like microvesicles found in neuronal and endocrine cells.
AB - Rab3A is a small GTP-binding protein expressed predominantly in brain and neuroendocrine cells, in which it is associated with synaptic and synaptic- like vesicles, respectively. Here we report that adult mouse fat cells and 3T3-L1 adipocytes also express Rab3A mRNA and protein. They do not express synaptophysin, an abundant protein in synaptic vesicles or synaptic-like vesicles. The amount of Rab3A mRNA and protein, like that of the highly homologous isoform Rab3D, increases severalfold during differentiation of 3T3-L1 fibroblasts into mature adipocytes. In fat cells, most Rab3D and Rab3A protein is bound to membrane, irrespective of insulin addition. Rab3A and Rab3D are localized in different subcellular compartments, since about half of the Rab3A, but none of the Rab3D, is associated with a low-density organelle(s). Rab3D and Rab3A may be involved in different pathways of regulated exocytosis in adipocytes. Moreover, in adipocytes Rab3A may define an exocytic organelle that is different from synaptic vesicles or synaptic- like microvesicles found in neuronal and endocrine cells.
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U2 - 10.1073/pnas.92.10.4284
DO - 10.1073/pnas.92.10.4284
M3 - Article
C2 - 7753798
AN - SCOPUS:0029018297
SN - 0027-8424
VL - 92
SP - 4284
EP - 4288
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
IS - 10
ER -