抄録
RNA helicases play important roles in various aspects of RNA metabolism, such as ribosome biogenesis, translation initiation and mRNA degradation. In general, RNA helicases are enzymes that unwind base paired RNAs. In the present study, we mutated the crhL gene for a cold-inducible RNA helicase with complete segregation of the native copy of the gene in Synechocystis sp. PCC 6803. The mutant of the RNA helicase (ΔcrhL) exhibited a phenotype of slow growth at low temperatures. DNA microarray and Northern blotting analyses indicated that the ΔcrhL mutation decreased the transcript levels of the groESL1 operon that encode the 10-kDa chaperonin and the 60-kDa chaperonin1 and the groEL2 gene that encode 60-kDa chaparonin2 under cold stress. The ΔcrhL mutation did not affect the stability of groESL1 transcript under cold stress. The involvement of RNA helicase in regulation of the expression of groESL1 and groEL2 genes will be discussed.
