D. Briant et al., EFFECT OF HERBIMYCIN-A ON HSP30 AND HSP70 HEAT-SHOCK-PROTEIN GENE-EXPRESSION IN XENOPUS CULTURED-CELLS, Biochemistry and cell biology, 75(6), 1997, pp. 777-782
We have examined the effect of herbimycin A, a benzoquinoid ansamycin
antibiotic, on the pattern of gene expression in amphibians. Exposure
of Xenopus laevis A6 kidney epithelial cells to 1 mu g/mL herbimycin A
induced the synthesis of the heat shock proteins hsp30 and hsp70 as w
ell as 33- and 45-kDa proteins. Enhanced synthesis of a 34-kDa protein
appears to be specific to herbimycin A because its synthesis did not
increase after heat shock (35 degrees C). In addition, the synthesis o
f hsp30 and hsp70 induced by herbimycin A was accompanied by an increa
se in their mRNAs. Herbimycin A induced a transient accumulation of hs
p30 and hsp70 mRNA, which peaked between 4 and 6 h. Finally, concurren
t treatment of cells with 0.5 mu g/mL herbimycin A anti a mild heat sh
ock of 27 degrees C yielded a synergistic accumulation of hsp30 and hs
p70 mRNA. These studies demonstrate that herbimycin A can induce the e
xpression of a set of stress proteins in amphibians and that concurren
t treatment with herbimycin A and mild heat shock has a synergistic ef
fect on the accumulation of hsp30 and hsp70 mRNA.