Van Dijk A M, King G B, Schotman P, Gispen W H
Neurochem Res. 1981 Aug;6(8):847-61. doi: 10.1007/BF00965043.
The effect of ACTH1-24 and cyclic nucleotides on the endogenous phosphorylation of proteins from a postmitochondrial supernatant from rat brainstem was investigated in the presence and absence of GTP. Phosphorylation and its modulation by these compounds were studied in vitro by incorporation of labeled phosphate from [gamma-32P]ATP added to the incubation mixture. Phosphoproteins were subsequently analyzed by autoradiography after one- and two-dimensional separation. Eight ACTH-sensitive phosphoproteins of molecular weights 75 (IEP 4.0), 67, 64, 50 (IEP 4.7), 47 (IEP 4.8), 38, 34, and 24K were found. The effects of ACTH on phosphorylation were mainly inhibitory, and the affected protein bands did not coincide with the phosphoproteins sensitive to cyclic AMP and cyclic GMP. Phosphorylation of those phosphoprotein bands and its ACTH sensitivity appeared to be highly sensitive to GTP. It is suggested that the activity of protein kinases involved in hormone-sensitive phosphorylation in a postmitochondrial rat brainstem fraction is regulated by GTP-dependent mechanisms.
在有和没有GTP的情况下，研究了促肾上腺皮质激素1-24（ACTH1-24）和环核苷酸对大鼠脑干线粒体后上清液中蛋白质内源性磷酸化的影响。通过将添加到孵育混合物中的[γ-32P]ATP中的标记磷酸盐掺入，在体外研究了这些化合物对磷酸化及其调节作用。随后，在一维和二维分离后通过放射自显影分析磷蛋白。发现了8种分子量分别为75（等电点4.0）、67、64、50（等电点4.7）、47（等电点4.8）、38、34和24K的ACTH敏感磷蛋白。ACTH对磷酸化的影响主要是抑制性的，受影响的蛋白带与对环磷酸腺苷（cAMP）和环磷酸鸟苷（cGMP）敏感的磷蛋白不一致。这些磷蛋白带的磷酸化及其对ACTH的敏感性似乎对GTP高度敏感。提示大鼠脑干线粒体后部分中参与激素敏感磷酸化的蛋白激酶活性受GTP依赖性机制调节。
