HSF1 activation occurs at different temperatures in somatic and male germ cells in the poikilotherm rainbow trout.
The heat shock factor 1 (HSF1) is the central actor of the response to hyperthermia in eukaryotic cells. In mammals, male germ cells are an exception among all cellular populations for their HSF1 activation occurs at low temperature. This feature was believed to be specific of homeotherms whose testicular compartment is located outside the main body cavity, where temperature is lower. In the present study, we show that in the poikilotherm rainbow trout, the maximal heat shock response of male germ cells, that are located in the same body compartment than the other organs, occurs also at a significantly lower temperature (22 degrees C) than for somatic cells (28 degrees C), regardless of culture conditions before heat shock. In addition, the acquisition of the HSE-binding activity of HSF1 upon heat shock is not associated with the classical hsp70 mRNA accumulation. Taken together, these results strongly suggest the existence of a particular mode of heat shock response that could be specific of male germ cells but not restricted to homeotherms.
Le Goff
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P
UPRES-A 6026 CNRS, Université de Rennes, 1, Campus de Beaulieu, Rennes Cedex, 35042, France. pascale.le-goff@univ-rennes1.fr
Michel
D
D
D000064:Acclimatization; D000818:Animals; D002460:Cell Line; D004268:DNA-Binding Proteins / Q000378:metabolism*; D005854:Germ Cells / Q000378:metabolism*; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics; D000076249:Heat Shock Transcription Factors; D008297:Male; D009687:Nuclear Proteins / Q000032:analysis; D017686:Oncorhynchus mykiss / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013696:Temperature; D013737:Testis / Q000378:metabolism; D014157:Transcription Factors; D014158:Transcription, Genetic
D004268:DNA-Binding Proteins; D018840:HSP70 Heat-Shock Proteins; D000076249:Heat Shock Transcription Factors; D009687:Nuclear Proteins; D012333:RNA, Messenger; D014157:Transcription Factors