Propofol activates and allosterically modulates recombinant protein kinase C epsilon.
Propofol activates and allosterically modulates recombinant protein kinase C epsilon.
复制标题
异丙酚激活并变构调节重组蛋白激酶 C epsilon。
DOI：
10.1097/aln.0b013e3181a3274b
复制
发表时间：
2009
期刊：
影响因子：
8.8
通讯作者：
Damron,DerekS
中科院分区：
文献类型：
--
作者：
Wickley,PeterJ;Yuge,Ryo;Martin,BradA;Meyer,JacobS;Damron,DerekS
Background Myocardial protection by anesthetics is known to involve activation of protein kinase C epsilon (PKCε). A key step in the activation process is auto-phosphorylation of the enzyme at serine 729. Our objectives were to identify the extent to which propofol interacts with PKCε and to identify the molecular mechanism(s) of interaction. Methods Immuno-blot analysis of recombinant PKCε was used to assess auto-phosphorylation of PKCε at serine 729 before and after exposure to propofol. An enzyme-linked immuno-absorbant assay kit was used for measuring PKC activity. Spectral shifts in fluorescence emission maxima of the C1B subdomain of PKCε in combination with the fluorescent phorbol ester, sapintoxin D, was used to identify molecular interactions between propofol and the phorbol ester/diacylglycerol binding site on the enzyme. Results Propofol (1 μM) caused a 6-fold increase in immuno-detectable, serine 729 phosphorylated PKCε and increased catalytic activity of the enzyme in a dose-dependent manner. DOG- or phorbol myristic acetate-induced activation of recombinant PKCε activity was enhanced by preincubation with propofol. Both propofol and phorbol myristic acetate quenched the intrinsic fluorescence spectra of the PKCε C1B subdomain in a dose-dependent manner, and propofol caused a further leftward-shift in the fluorescence emission maxima of sapintoxin D following addition of the C1B subdomain. Conclusions These results demonstrate that propofol interacts with recombinant PKCε causing auto-phosphorylation and activation of the enzyme. Moreover, propofol enhances phorbol ester-induced catalytic activity suggesting propofol binds to a region near the phorbol ester binding site allowing for allosteric modulation of PKCε catalytic activity.
