TY - JOUR
T1 - Regulation of WNK1 by an autoinhibitory domain and autophosphorylation
AU - Xu, Bing e.
AU - Min, Xiaoshan
AU - Stippec, Steve
AU - Lee, Byung Hoon
AU - Goldsmith, Elizabeth J.
AU - Cobb, Melanie H.
PY - 2002/12/13
Y1 - 2002/12/13
N2 - WNK family protein kinases are large enzymes that contain the catalytic lysine in a unique position compared with all other protein kinases. These enzymes have been linked to a genetically defined form of hypertension. In this study we introduced mutations to test hypotheses about the position of the catalytic lysine, and we examined mechanisms involved in the regulation of WNK1 activity. Through the analysis of enzyme fragments and sequence alignments, we have identified an autoinhibitory domain of WNK1. This isolated domain, conserved in all four WNKs, suppressed the activity of the WNK1 kinase domain. Mutation of two key residues in this autoinhibitory domain attenuated its ability to inhibit WNK kinase activity. Consistent with these results, the same mutations in a WNK1 fragment that contain the autoinhibitory domain increased its kinase activity. We also found that WNK1 expressed in bacteria is autophosphorylated; autophosphorylation on serine 382 in the activation loop is required for its activity.
AB - WNK family protein kinases are large enzymes that contain the catalytic lysine in a unique position compared with all other protein kinases. These enzymes have been linked to a genetically defined form of hypertension. In this study we introduced mutations to test hypotheses about the position of the catalytic lysine, and we examined mechanisms involved in the regulation of WNK1 activity. Through the analysis of enzyme fragments and sequence alignments, we have identified an autoinhibitory domain of WNK1. This isolated domain, conserved in all four WNKs, suppressed the activity of the WNK1 kinase domain. Mutation of two key residues in this autoinhibitory domain attenuated its ability to inhibit WNK kinase activity. Consistent with these results, the same mutations in a WNK1 fragment that contain the autoinhibitory domain increased its kinase activity. We also found that WNK1 expressed in bacteria is autophosphorylated; autophosphorylation on serine 382 in the activation loop is required for its activity.
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U2 - 10.1074/jbc.M207917200
DO - 10.1074/jbc.M207917200
M3 - Article
C2 - 12374799
AN - SCOPUS:2242435334
SN - 0021-9258
VL - 277
SP - 48456
EP - 48462
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 50
ER -