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.
Ayme
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Southgate
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Tissières
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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