Mutual interaction study between dnak-groel-ftsh with heat shock regulator σ32 to explain prokaryotic heat shock regulation

Abstract

Heat shock response in Escherichia coli is mainly controlled by the alternative transcription factor σ32. This response leads to an up-regulation of heat shock proteins including chaperones and proteases. The activity and stability of σ32 is in turn altered through mutual interactions with these heat shock proteins. The work reported here mainly deals with the docking of σ32 with the chaperone GroEL and protease FtsH. The findings of the above studies together with the σ32—DnaK docking study reported earlier suggest that the binding of σ32 with GroEL and DnaK at normal temperature is stronger compared to those at high temperature. With rise in temperature σ32 adopts an open conformation and this probably favors binding with FtsH and renders it for degradation by FtsH.