کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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1934943 | 1050653 | 2008 | 5 صفحه PDF | دانلود رایگان |

Purified recombinant human subunits of eukaryotic initiation factor 2 (eIF2) expressed in bacteria are found to interact with each other to form αβ, αγ, and βγ complexes in a pull-down experiment. Recombinant phosphorylated human eIF2α that cannot interact with purified eIF2B, the GDP/GTP exchange factor of eIF2, however interacts efficiently with eIF2B along with the β-subunit of eIF2 of the rabbit reticulocyte lysates and also with the purified recombinant β-subunit. These findings therefore suggest that the β-subunit of eIF2 mediates the productive and non-productive interactions between eIF2 and 2B. Recombinant α and β-subunits serve as substrates for not only kinases but also for caspase 3 and interestingly phosphorylated subunits resist caspase action. Phosphorylation also modifies the β-subunit’s interaction with Nck1, a cofactor of eIF2α phosphatase, but not with eIF5, the GTPase activating protein. These findings suggest that subunits of mammalian eIF2 interact with each other and the β-subunit plays a critical role both in the regulation and function of eIF2.
Journal: Biochemical and Biophysical Research Communications - Volume 374, Issue 2, 19 September 2008, Pages 336–340