Nucleotide sequences responsible for the thermal inducibility of the Drosophila small heat-shock protein genes in monkey COS cells.
The promoter regions of the Drosophila melanogaster small heat-shock protein genes have been analysed in order to localize those sequences responsible for their heat-shock transcriptional inducibility. Different lengths of the 5' DNA sequences of these four genes were each fused individually to the Herpes simplex virus thymidine kinase (HSV-tk) transcription unit. These hybrid genes were constructed in a simian virus 40 recombinant vector for transfection in permissive monkey COS cells and tested for their heat-shock inducibility. The hsp22/HSV-tk and hsp26/HSV-tk fusion genes were found to be heat-inducible at 43 degrees C, giving rise to correctly initiated transcripts, but transcriptionally quiescent at 37 degrees C (control temperature). The hsp23 and hsp27 fusion gene constructs are, however, not heat-shock-inducible; no transcripts being detectable from hsp27/HSV-tk constructs at either temperature and all hsp23/HSV-tk clones being faithfully but constitutively expressed at low levels at both temperatures. By testing a series of 5' deletion mutants in hsp22/HSV-tk, a homologous sequence located adjacent to the TATA box in both the hsp22 and hsp26 genes was identified as being responsible for their heat-shock activation. This control element corresponds to the Pelham "consensus sequence", previously described for the Drosophila hsp70 genes. The possible modes of transcriptional induction of all four genes are discussed.
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D000818:Animals; D001483:Base Sequence; D002478:Cells, Cultured; D004247:DNA; D004262:DNA Restriction Enzymes; D004331:Drosophila melanogaster; D004591:Electrophoresis, Polyacrylamide Gel; D005796:Genes; D000882:Haplorhini; D006360:Heat-Shock Proteins / Q000235:genetics*; D006358:Hot Temperature; D009876:Operon; D012313:RNA / Q000032:analysis; D014158:Transcription, Genetic
D006360:Heat-Shock Proteins; D012313:RNA; D004247:DNA; D004262:DNA Restriction Enzymes