Phosphorylation of the alpha-subunit of plant eukaryotic initiation factor 2 prevents its association with polysomes but does not considerably suppress protein synthesis.

Phosphorylation of the α-subunit of eukaryotic initiation factor 2 (eIF2α) and subsequent inhibition of protein synthesis is a major survival response to different stresses in animal and yeast cells. However, the role of this regulatory mechanism in plants is not unambiguously established to date. Here we describe a slight reduction of polysome abundance in Nicotiana benthamiana after the transient expression of a cDNA, AteIF2α(S56D), encoding a phosphomimetic form of Arabidopsis thaliana eIF2α.

Evidence That Phosphorylation of the -Subunit of eIF2 Does Not Essentially Inhibit mRNA Translation in Wheat Germ Cell-Free System.

A mechanism based on reversible phosphorylation of the -subunit of eukaryotic initiation factor 2 (eIF2) has been confirmed as an important regulatory pathway for the inhibition of protein synthesis in mammalian and yeast cells, while plants constitute the significant exception. We studied the induction of eIF2 phosphorylation in germinated wheat () embryos subjected to different adverse conditions. Data confirmed that formation of eIF2(P) was not a general response, as no phosphorylation was observed under salt, oxidative, or heat stress.