Inhibition of nucleoside diphosphate kinase activity by in vitro phosphorylation by protein kinase CK2. Differential phosphorylation of NDP kinases in HeLa cells in culture.
Although a number of nucleoside diphosphate kinases (NDPKs) have been reported to act as inhibitors of metastasis or as a transcription factor in mammals, it is not known whether these functions are linked to their enzymatic activity or how this protein is regulated. In this report, we show that in vitro protein kinase CK2 catalyzed phosphorylation of human NDPK A inhibits its enzymatic activity by inhibiting the first step of its ping-pong mechanism of catalysis: its autophosphorylation. Upon in vivo 32P labeling of HeLa cells, we observed that both human NDPKs, A and B, were autophosphorylated on histidine residues, however, only the B isoform appeared to be serine phosphorylated.
Biondi
R M
RM
Cátedra de Microbiologá, Facultad de Agronomía, Universidad de Buenos Aires, CIBYF (CONICET), Argentina.
Engel
M
M
Sauane
M
M
Welter
C
C
Issinger
O G
OG
Jiménez de Asúa
L
L
Passeron
S
S
D047390:Casein Kinase II; D002384:Catalysis; D006367:HeLa Cells; D006801:Humans; D009701:Nucleoside-Diphosphate Kinase / Q000037:antagonists & inhibitors* / Q000378:metabolism; D010766:Phosphorylation; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D011994:Recombinant Proteins / Q000378:metabolism
D011994:Recombinant Proteins; D047390:Casein Kinase II; D017346:Protein Serine-Threonine Kinases; D009701:Nucleoside-Diphosphate Kinase