Eukaryotic protein synthesis initiation factor 2

• Published in: European journal of biochemistry Vol. 197; no. 3; pp. 623 - 629
• Main Authors: KUDLICKI, Wieslaw, PICKING, William D., KRAMER, Gisela, HARDESTY, Boyd, SMAILOV, Salim K., MUKHAMEDZHANOV, Bektas G., LEE, Anatoly V., ISKAKOV, Bulat K.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.05.1991
• ISSN: 0014-2956; 1432-1033
• DOI: 10.1111/j.1432-1033.1991.tb15952.x

Polyproanthocyanidin (PPA), a phenolic polymer isolated from the plant Alhagi kirgisorum S. was found to interact strongly with eukaryotic initiation factor 2 (eIF‐2), thereby inhibiting reactions involving this protein. When added to a rabbit reticulocyte lysate system, PPA blocks in vitro translation and it appears to selectively bind and precipitate a relatively small number of proteins including eIF‐2 and regulin. The phosphorylation of purified regulin and eIF‐2 by casein kinase II (CK II) and the heme‐sensitive eIF‐2α kinase, respectively, was also inhibited by the polyphenolic compound. The natural fluorescence of PPA was utilized to compare its interaction with eIF‐2 and regulin to that with other natural and synthetic polypeptides.