Phosphorylation of Rabphilin-3A by calmodulin-dependent protein kinase II.
Rabphilin-3A is a putative target protein for Rab3A small GTP-binding protein which is implicated in neurotransmitter release. We have examined here whether Rabphilin-3A is phosphorylated by calmodulin-dependent protein kinase II (CaMKII). Recombinant Rabphilin-3A was phosphorylated by CaMKII purified from rat brain. Two moles of phosphate were maximally incorporated into one mole of Rabphilin-3A. The phosphorylation sites were Ser34, Thr205, Thr209, and Thr537. These results suggest that the CaMKII-catalyzed phosphorylation of Rabphilin-3A may modulate neurotransmitter release.
Kato
M
M
Department of Molecular Biology and Biochemistry, Osaka University Medical School, Suita, Japan.
Sasaki
T
T
Imazumi
K
K
Takahashi
K
K
Araki
K
K
Shirataki
H
H
Matsuura
Y
Y
Ishida
A
A
Fujisawa
H
H
Takai
Y
Y
D048868:Adaptor Proteins, Signal Transducing; D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites / Q000235:genetics; D001921:Brain / Q000201:enzymology; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000378:metabolism*; D002474:Cell-Free System; D003001:Cloning, Molecular; D019204:GTP-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D066298:In Vitro Techniques; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism*; D018377:Neurotransmitter Agents / Q000378:metabolism; D010766:Phosphorylation; D051381:Rats; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D018411:Spodoptera; D033921:Vesicular Transport Proteins; D020691:rab GTP-Binding Proteins; D000097624:Rabphilin-3A
D048868:Adaptor Proteins, Signal Transducing; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D019204:GTP-Binding Proteins; D009419:Nerve Tissue Proteins; D018377:Neurotransmitter Agents; D011994:Recombinant Proteins; D033921:Vesicular Transport Proteins; D020691:rab GTP-Binding Proteins; D000097624:Rabphilin-3A