TY - JOUR
T1 - Phosphorylation of helix-loop-helix proteins ID1, ID2 and ID3
AU - Nagata, Yuka
AU - Shoji, Wataru
AU - Obinata, Masuo
AU - Todokoro, Kazuo
PY - 1995/2/27
Y1 - 1995/2/27
N2 - Id is a helix-loop-helix protein which forms heterodimer with ubiquitous and/or tissue-specific basic helix-loop-helix proteins and inhibits their DNA binding. It has been noted that putative phosphorylation sites for various protein kinases exist in rat Id1, Id2 and Id3. We show here that Id1 and Id2 can be phosphorylated in vitro by cAMP-dependent protein kinase, Id2 and Id3 by cdc2 kinase, and all three Ids by protein kinase C. The phosphorylated Id1 was actually immunoprecipitated in nerve-growth-factor-stimulated PC12 cells. Gel mobility shift assays, however, demonstrated that neither phosphorylation of Id proteins by cAMP-dependent protein kinase nor phosphorylation of E47 by protein kinase C affected the inhibition of E47 homodimer formation and its DNA binding. Taken together with other observations, phosphorylation of Id proteins may play a role in regulation of cell differentiation but not directly in the dimerization and DNA binding.
AB - Id is a helix-loop-helix protein which forms heterodimer with ubiquitous and/or tissue-specific basic helix-loop-helix proteins and inhibits their DNA binding. It has been noted that putative phosphorylation sites for various protein kinases exist in rat Id1, Id2 and Id3. We show here that Id1 and Id2 can be phosphorylated in vitro by cAMP-dependent protein kinase, Id2 and Id3 by cdc2 kinase, and all three Ids by protein kinase C. The phosphorylated Id1 was actually immunoprecipitated in nerve-growth-factor-stimulated PC12 cells. Gel mobility shift assays, however, demonstrated that neither phosphorylation of Id proteins by cAMP-dependent protein kinase nor phosphorylation of E47 by protein kinase C affected the inhibition of E47 homodimer formation and its DNA binding. Taken together with other observations, phosphorylation of Id proteins may play a role in regulation of cell differentiation but not directly in the dimerization and DNA binding.
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U2 - 10.1006/bbrc.1995.1273
DO - 10.1006/bbrc.1995.1273
M3 - Article
C2 - 7864897
AN - SCOPUS:0028929206
VL - 207
SP - 916
EP - 926
JO - Biochemical and Biophysical Research Communications
JF - Biochemical and Biophysical Research Communications
SN - 0006-291X
IS - 3
ER -