Hovland R, Eikhom T S, Proud C G, Cressey L I, Lanotte M, Døskeland S O, Houge G
Department of Anatomy and Cell Biology, University of Bergen, Norway.
FEBS Lett. 1999 Feb 5;444(1):97-101. doi: 10.1016/s0014-5793(99)00039-3.
Treatment of IPC-81 cells led to inhibition of protein synthesis, which was accompanied by an increase in the average size of polysomes and a decreased rate of elongation, indicating that it involved inhibition of peptide chain elongation. This inhibition was also associated with increased phosphorylation of elongation factor eEF2 (which inhibits its activity) and enhanced Ca2+/calmodulin-independent activity of eEF2 kinase. Previous work has shown that phosphorylation of eEF2 kinase by cAMP-dependent protein kinase (cAPK) in vitro induces such activator-independent activity, and the present data show that such a mechanism can occur in intact cells to link physiological levels of cAPK activation with inhibition of protein synthesis.
对IPC - 81细胞的处理导致蛋白质合成受到抑制，同时伴随着多核糖体平均大小的增加和延伸速率的降低，这表明其涉及肽链延伸的抑制。这种抑制还与延伸因子eEF2的磷酸化增加（抑制其活性）以及eEF2激酶的Ca2 + /钙调蛋白非依赖性活性增强有关。先前的研究表明，在体外，cAMP依赖性蛋白激酶（cAPK）使eEF2激酶磷酸化可诱导这种非激活剂依赖性活性，目前的数据表明这种机制可在完整细胞中发生，将cAPK激活的生理水平与蛋白质合成的抑制联系起来。
