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. 1984 Nov;81(22):6998–7002. doi: 10.1073/pnas.81.22.6998

Distribution of reversing factor in reticulocyte lysates during active protein synthesis and on inhibition by heme deprivation or double-stranded RNA.

N S Thomas, R L Matts, R Petryshyn, I M London
PMCID: PMC392063  PMID: 6594676

Abstract

We have recently shown a direct correlation between protein synthetic activity and the function of reversing factor (RF) as a catalyst of GDP-GTP exchange in whole reticulocyte lysates under normal conditions and on inhibition of protein synthesis by heme deficiency, double-stranded RNA, or oxidized glutathione. In this paper we report that RF is detectable as a nonribosomal complex with eukaryotic initiation factor 2 phosphorylated in its alpha subunit [eIF-2(alpha P)] in whole lysates inhibited by heme deprivation or by double-stranded RNA. The complex contains no unphosphorylated eIF-2 alpha, and the GDP present is freely dissociable. All nonribosomal eIF-2(alpha P) is complexed with RF in fully inhibited lysates; we have not detected free eIF-2(alpha P). RF in this [RF X eIF-2(alpha P)] complex is unavailable to catalyze the release of GDP from eIF-2-GDP. Dephosphorylation of eIF-2(alpha P) present in nonribosomal fractions releases active RF, which is able to carry out its normal guanine nucleotide exchange function.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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