Ral and Rab3a are major GTP-binding proteins of axonal rapid transport and synaptic vesicles and do not redistribute following depolarization stimulated synaptosomal exocytosis.
We have employed high-resolution SDS polyacrylamide gels to demonstrate that there are two major low-molecular-weight GTP-binding proteins associated with axonal membranes including synaptic vesicles, rapid transported membranes and clathrin-coated vesicles. We demonstrate that one of the major proteins is Ral and that the other is Rab3A. Following the depolarization of synaptosomes resulting in increased neurotransmitter release, we see no significant dissociation of either Ral or Rab3a from synaptic vesicle derived membranes in contrast to results reported previously.
Bielinski
D F
DF
Department of Biochemistry, Boston University School of Medicine, MA 02118.
Pyun
H Y
HY
Linko-Stentz
K
K
Macara
I G
IG
Fine
R E
RE
D000595:Amino Acid Sequence; D000818:Animals; D000906:Antibodies / Q000276:immunology; D002118:Calcium / Q000494:pharmacology; D002417:Cattle; D005089:Exocytosis / Q000187:drug effects; D019204:GTP-Binding Proteins / Q000276:immunology / Q000302:isolation & purification / Q000378:metabolism*; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D010446:Peptide Fragments / Q000032:analysis; D011817:Rabbits; D051381:Rats; D013572:Synaptic Vesicles / Q000378:metabolism*; D013574:Synaptosomes / Q000378:metabolism; D014357:Trypsin; D020692:rab3 GTP-Binding Proteins; D020725:ral GTP-Binding Proteins
D000906:Antibodies; D009419:Nerve Tissue Proteins; D010446:Peptide Fragments; D014357:Trypsin; D019204:GTP-Binding Proteins; D020692:rab3 GTP-Binding Proteins; D020725:ral GTP-Binding Proteins; D002118:Calcium