Gil C, Plana M, Riera M, Itarte E
Departament de Bioquímica i de Biologia Molecular, Universitat Autònoma de Barcelona, Bellaterra, Spain.
Biochem Biophys Res Commun. 1996 Aug 23;225(3):1052-7. doi: 10.1006/bbrc.1996.1293.
Comparison of the amino acid sequences of two peptides derived from proteolysis of rat liver pp49 identified it as composed of the beta-subunit and the gamma-subunit of eukaryotic initiation factor-2 (eIF-2). Partial purification of rat liver eIF-2 showed that its trimeric form (alpha beta gamma) co-eluted with protein kinase CK2. Heat-inactivated preparations of the trimeric form of eIF-2 inhibited CK2, increasing its Km for beta-casein, as observed with pp49. The form of eIF-2 that lacks the beta-subunit had no effect on CK2. These data indicate that the beta gamma subunits of eIF-2 may complex with CK2 and modulate its activity.
对源自大鼠肝脏pp49蛋白水解的两种肽的氨基酸序列进行比较后，确定其由真核生物起始因子2（eIF-2）的β亚基和γ亚基组成。大鼠肝脏eIF-2的部分纯化表明，其三聚体形式（αβγ）与蛋白激酶CK2共同洗脱。eIF-2三聚体形式的热失活制剂抑制CK2，增加其对β-酪蛋白的Km值，正如pp49所观察到的那样。缺乏β亚基的eIF-2形式对CK2没有影响。这些数据表明，eIF-2的βγ亚基可能与CK2结合并调节其活性。
