Identification of stathmin as a novel substrate for p38 delta.
p38 mitogen-activated protein kinases (MAPK) are a family of kinases that are activated by cellular stresses and inflammatory cytokines. Although there are many similarities shared by the isoforms of p38 (alpha, beta, gamma, and delta), p38 delta differs from the others in some respects such as inhibitor sensitivity and substrate specificity. Utilizing in a solution kinase assay, we identified a novel p38 delta substrate as stathmin. Stathmin is a cytoplasmic protein that was previously reported to be a substrate of several intracellular signaling kinases and has recently been linked to regulation of microtubule dynamics. p38 delta has significantly higher in vitro phosphorylating activity against stathmin than other p38 isoforms or related MAPKs. In transient expression studies, we found that in addition to different stimuli osmotic stress activates p38 delta to phosphorylate stathmin. The sites of phosphorylation were mapped to Ser-25 and Ser-38, both in vitro and in cells.
Parker
C G
CG
Amgen Inc., Boulder Colorado 80301, USA.
Hunt
J
J
Diener
K
K
McGinley
M
M
Soriano
B
B
Keesler
G A
GA
Bray
J
J
Yao
Z
Z
Wang
X S
XS
Kohno
T
T
Lichenstein
H S
HS
D001483:Base Sequence; D001665:Binding Sites / Q000235:genetics; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000378:metabolism*; D002460:Cell Line; D017931:DNA Primers / Q000235:genetics; D004789:Enzyme Activation; D004926:Escherichia coli / Q000235:genetics; D006801:Humans; D066298:In Vitro Techniques; D048031:JNK Mitogen-Activated Protein Kinases; D048369:MAP Kinase Kinase 1; D008868:Microtubule Proteins; D020929:Mitogen-Activated Protein Kinase Kinases; D020928:Mitogen-Activated Protein Kinases; D009997:Osmotic Pressure; D010750:Phosphoproteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D010766:Phosphorylation; D016133:Polymerase Chain Reaction; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D011505:Protein-Tyrosine Kinases / Q000378:metabolism; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D012694:Serine / Q000737:chemistry; D050777:Stathmin; D013379:Substrate Specificity; D014162:Transfection; D048051:p38 Mitogen-Activated Protein Kinases
D017931:DNA Primers; D008868:Microtubule Proteins; D010750:Phosphoproteins; D011994:Recombinant Proteins; C493995:STMN1 protein, human; D050777:Stathmin; D012694:Serine; D011505:Protein-Tyrosine Kinases; D017346:Protein Serine-Threonine Kinases; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D048031:JNK Mitogen-Activated Protein Kinases; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases; D048369:MAP Kinase Kinase 1; C482125:MAP2K1 protein, human; D020929:Mitogen-Activated Protein Kinase Kinases