Möglich Andreas, Ayers Rebecca A, Moffat Keith
Department of Biochemistry and Molecular Biology, Institute for Biophysical Dynamics, University of Chicago, Chicago, IL 60637, USA.
J Mol Biol. 2009 Feb 6;385(5):1433-44. doi: 10.1016/j.jmb.2008.12.017. Epub 2008 Dec 14.
Signal transduction proteins are organized into sensor (input) domains that perceive a signal and, in response, regulate the biological activity of effector (output) domains. We reprogrammed the input signal specificity of a normally oxygen-sensitive, light-inert histidine kinase by replacing its chemosensor domain by a light-oxygen-voltage photosensor domain. Illumination of the resultant fusion kinase YF1 reduced net kinase activity by approximately 1000-fold in vitro. YF1 also controls gene expression in a light-dependent manner in vivo. Signals are transmitted from the light-oxygen-voltage sensor domain to the histidine kinase domain via a 40 degrees -60 degrees rotational movement within an alpha-helical coiled-coil linker; light is acting as a rotary switch. These signaling principles are broadly applicable to domains linked by alpha-helices and to chemo- and photosensors. Conserved sequence motifs guide the rational design of light-regulated variants of histidine kinases and other proteins.
信号转导蛋白被组织成传感(输入)结构域,这些结构域感知信号,并相应地调节效应器(输出)结构域的生物活性。我们通过用一个光氧电压光传感器结构域替换其化学传感器结构域,对一种通常对氧敏感、对光不敏感的组氨酸激酶的输入信号特异性进行了重新编程。对所得融合激酶YF1进行光照,在体外使净激酶活性降低了约1000倍。YF1在体内也以光依赖的方式控制基因表达。信号通过α-螺旋卷曲螺旋连接子内40度-60度的旋转运动从光氧电压传感器结构域传递到组氨酸激酶结构域;光起着旋转开关的作用。这些信号传导原理广泛适用于由α-螺旋连接的结构域以及化学传感器和光传感器。保守的序列基序指导组氨酸激酶和其他蛋白质的光调节变体的合理设计。