Cloning, Characterization, and Transcriptional Analysis of a Gene Encoding an α-Crystallin-Related, Small Heat Shock Protein from the Thermophilic Cyanobacterium Synechococcus vulcanus

hspA, a gene encoding a 16-kDa heat-induced protein from the thermophilic cyanobacterium Synechococcus vulcanus, has been cloned and sequenced. The deduced amino acid sequence of the gene product showed significant homology to sequences of the family of α-crystallin-related, small heat shock proteins. A monocistronic mRNA of hspA increased transiently in response to heat shock. The heat shock induction occurred at a vegetative promoter but without the CIRCE (controlling inverted repeat of chaperone expression) element.