Toktarova M V, Kulichkova V A, Mittenberg A G, Kozhukharova I V, Volkova I V, Ermolaeva Iu B, Peshekhonov A V, Ignatova T N, Gauze L N, Konstantinova I M
Institute of Cytology RAS, St. Petersburg.
Tsitologiia. 2004;46(3):283-90.
It has been shown that endoribonuclease activity of alpha-RNP particles and 26S proteasomes are changed under the action of inductors of programmed cell death. Treatment of K562 cells with inductors of apoptosis--doxorubicin (adriamycin) and diethylmaleate--lead to a significant stimulation of RNAse activity of alpha-RNP and to reduction of proteasome RNase activity. The enzymatic activity under study has been shown to be specifically and selectively dependent on phosphorylation of subunits of alpha-RNP particles and 26S proteasomes. The characteristics of RNAse activity of different subpopulations of proteasomes differ. The specificity of a subpopulation of proteasomes exported from the cell has been demonstrated. Proteasome and alpha-RNP involvement in the coordinated control of stability of various specific messenger RNA molecules is suggested, and one of the mechanisms of this control might be the export of specific subpopulation of proteasomes from the cell.
研究表明，在程序性细胞死亡诱导剂的作用下，α - RNP颗粒和26S蛋白酶体的核糖核酸内切酶活性会发生变化。用凋亡诱导剂——阿霉素（ Adriamycin ）和马来酸二乙酯处理K562细胞，会导致α - RNP的核糖核酸酶活性显著增强，而蛋白酶体核糖核酸酶活性降低。研究表明，所研究的酶活性特异性且选择性地依赖于α - RNP颗粒和26S蛋白酶体亚基的磷酸化。不同亚群的蛋白酶体核糖核酸酶活性特征不同。已证实从细胞中输出的蛋白酶体亚群具有特异性。有人提出蛋白酶体和α - RNP参与了对各种特定信使RNA分子稳定性的协调控制，这种控制的机制之一可能是特定亚群的蛋白酶体从细胞中输出。
