The transcripts of several components of the protein synthesis machinery are cold-regulated in a chloroplast-dependent manner in barley and wheat

Nine clones coding different components of the protein synthesis machinery were selected from an EST barley library prepared from cold exposed plants and tested for their expression at low temperature. Northern analysis revealed that expression of elongation factor (EF) 1Bβ and two ribosomal protein (RP) genes S7 and L7A was enhanced following exposure to 3°C, but not during dehydration or exogenous ABA treatment. The mRNA levels of EF1Bβ, RPS7, and RPL7A did not vary between cultivars with different frost tolerance, but differences in expression were found between different species. Experiments with an albino mutant and etiolated plants revealed that the cold-dependent regulation of EF1Bβ, RPS7, and RPL7A transcripts is controlled by a chloroplast-related pathway impaired in the mutant.