9752978 Vierling This is a POWRE Research Enhancement Award. The immediate goal of this project is to establish a genetic approach, using the cyanobacterium Synechocystis sp. PCC 6803, for structure and function analysis of a new class of molecular chaperone, the small heat shock proteins (sHSPs). These ubiquitous stress proteins, found in both eukaryotes and prokaryotes, accumulate during heat stress in virtually all organisms, and appear to also have a role in certain developmental and growth stage transitions in many organisms. While a working model for the sHSPs exists, there are essentially no data on the mechanistic details of sHSP action, and very little direct in vivo data to support the model. Recently, Dr. H. Fukuzawa at Kyoto University discovered that deletion of the single sHSP gene in the cyanobacterium Synechocystis, HSP16.6, leads to inability to develop thermotolerance but does not affect normal cell growth. This is the first demonstration that a prokaryotic sHSP is required for high temperature tolerance, and is the first phenotype associated with an sHSP mutant in any organism other than the fungus Neurospora. Since Synechocystis can be easily manipulated genetically, this discovery affords an excellent opportunity for detailed analysis of sHSP structure and function. Synechocystis carries the further advantage that its complete genome has been sequenced. The project will be carried out in collaboration with H. Fukuzawa at Kyoto University in Japan. This award provides support toward the acquisition of equipment necessary for the culture of the cyanobacteria in Dr. Vierling's laboratory. The acquisition of this equipment is critical to the initiation of this project. ***
