Identification of phosphorylation sites on glial fibrillary acidic protein for cdc2 kinase and Ca(2+)-calmodulin-dependent protein kinase II.
We identified the phosphorylation sites of glial fibrillary acidic protein (GFAP) for cdc2 kinase and Ca(2+)-calmodulin (CaM)-dependent protein kinase II. GFAP was phosphorylated to approximately 0.2 mol of phosphate/mol of GFAP by cdc2 kinase, and this phosphorylation did not induce disassembly of the filament structure. On the other hand, GFAP was phosphorylated to approximately 1.9 mol of phosphate/mol of GFAP by Ca(2+)-CaM-dependent protein kinase II, and this phosphorylation did induce disassembly of the filament. Sequential analysis of the purified phosphopeptides revealed that only Ser8 on GFAP was phosphorylated by cdc2 kinase, whereas Ser13, Ser17, Ser34, and Ser389 on GFAP were phosphorylated by Ca(2+)-CaM-dependent protein kinase II.
Tsujimura
K
K
Department of Neurophysiology, Tokyo Metropolitan Institute of Gerontology.
Tanaka
J
J
Ando
S
S
Matsuoka
Y
Y
Kusubata
M
M
Sugiura
H
H
Yamauchi
T
T
Inagaki
M
M
D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D016203:CDC2 Protein Kinase / Q000378:metabolism*; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000378:metabolism*; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism* / Q000648:ultrastructure*; D007381:Intermediate Filament Proteins / Q000378:metabolism; D008938:Mitosis / Q000502:physiology; D008969:Molecular Sequence Data; D010766:Phosphorylation; D051381:Rats
D005904:Glial Fibrillary Acidic Protein; D007381:Intermediate Filament Proteins; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D016203:CDC2 Protein Kinase