Exon-intron structure and sequence variation of the hsp-90 gene in the entomopathogenic nematode Heterorhabditis bacteriophora

The hsp-90 represents one of the most abundant and evolutionarily conserved proteins that are present in a wide range of organisms from bacteria to humans, functioning both as molecular chaperones and stress proteins. Nematodes are among the most successful organisms in withstanding stress conditions. Little is known about biochemical and molecular events underpinning entomopathogenic nematode responses to environmental stresses, in particular cold and heat stresses. In this study, we report the isolation and molecular characterization of the full-length cDNA of hsp-90 and its correspondlng gene from the entomopathogenic nematodes Heterorhabdltis bacteriophora. Sequencing analyses of several cDNA and genomic clones revealed the presence of different transcripts and genes. The unexpected finding of intron presence-absence in the hsp-90 genes of H. bacteriophora opens some questions about their functlon and their evolutionary significance. Further investigations are ongoing in order to assess the function of the different transcripts in response to different temperature stresses.