G. Sconzo et al., ACTIVATION BY HEAT-SHOCK OF HSP70 GENE-TRANSCRIPTION IN SEA-URCHIN EMBRYOS, Biochemical and biophysical research communications, 217(3), 1995, pp. 1032-1038
We had previously shown that P. lividus embryos subjected to heat shoc
k are unable to synthesize proteins of the hsp70 family at a detectabl
e level before the hatching blastula stage. We show here that this is
not due to the inability to synthesize the hsp70 mRNAs, which are dete
ctable following heat shock also in early stages, although in much low
er amounts per embryo than in later stages. These mRNAs are also trans
lated, as judged by the facts that they are present in the polysomal p
ellet, and that they are translatable in a cell free system. As to the
question of the amount of hsp70 RNAs per nucleus, we conclude that th
is is also higher in later than in earlier stages. The presence of hsp
70 mRNAs is already detectable after heating at 4 centigrades above 20
and their amount increases with the increase of temperature in the ra
nge between 24 degrees C and 28 degrees C. (C) 1995 Academic Press, In
c.