Abstract
We have previously identified four homologues of the molecular chaperone dnaJ (dnaJ1 ~ dnaJ4 ) in the genome of unicellular cyanobacterium Synechococcus sp. PCC7942, with only DnaJ3 protein was localized to thylakoid membrane. Our genetic analysis revealed that syc1092 null mutation suppresses temperature sensitive mutation of dnaJ3 gene. Syc1092 was widely conserved from cyanobacteria to higher plant, but the function is unknown.To investigate Syc1092 function, we carried out yeast two-hybrid screening suggested a specific interaction between Syc1092 and beta subunit of RNA polymerase complex. In addition, Syc1092 overexpressing strain showed temperature sensitive and the heat shock induction of hspA transcripts was compared with that of the wild type strain by using RT-PCR. The results indicated that Syc1092 negatively regulated the hspA induction.
