MacDonald J A, Eto M, Borman M A, Brautigan D L, Haystead T A
Department of Pharmacology, Duke University Medical Center, PO Box 3813, Durham, NC 27710, USA.
FEBS Lett. 2001 Mar 30;493(2-3):91-4. doi: 10.1016/s0014-5793(01)02277-3.
Phosphorylation of CPI-17 and PHI-1 by the MYPT1-associated kinase (M110 kinase) was investigated. M110 kinase is a recently identified serine/threonine kinase with a catalytic domain that is homologous to that of ZIP kinase (ZIPK. GST-rN-ZIPK, a constitutively active GST fusion fragment, phosphorylates CPI-17 (but not PHI-1) to a stoichiometry of 1.7 mol/mol. Phosphoamino acid analysis revealed phosphorylation of both Ser and Thr residues. Phosphorylation sites in CPI-17 were identified as Thr 38 and Ser 12 using Edman sequencing with (32)P release and a point mutant of Thr 38.
研究了与MYPT1相关的激酶（M110激酶）对CPI-17和PHI-1的磷酸化作用。M110激酶是最近鉴定出的一种丝氨酸/苏氨酸激酶，其催化结构域与ZIP激酶（ZIPK）的催化结构域同源。GST-rN-ZIPK是一种组成型活性GST融合片段，它以1.7摩尔/摩尔的化学计量比使CPI-17（而非PHI-1）磷酸化。磷酸氨基酸分析显示丝氨酸和苏氨酸残基均发生了磷酸化。使用(32)P释放的埃德曼测序法和苏氨酸38的点突变体，确定了CPI-17中的磷酸化位点为苏氨酸38和丝氨酸12。
