Mammalian HSP90 alpha and HSP90 beta are encoded by two individual genes, O
n the basis of the upstream sequences of the human hsp90 alpha gene, GenBan
k accession number U25822,,ve have constructed CAT reporter plasmids driven
by individual fragments of the hsp90 alpha gene. We found that (1) the pro
ximal heat shock element complex located at -96/-60 enhances hsp90a promote
r expression; (2) heat shock induction depends upon the coexistence of dist
al heat shock element at -1031/-1022 and the proximal heat shock element co
mplex of the hsp90 alpha gene; (3) unlike hsp90 beta, downstream sequences
of the transcription start site inhibit hsp90a expression, We conclude that
the regulatory mechanisms for the expression of hsp90 alpha and hsp90 beta
genes are different, (C) 1999 Federation of European Biochemical Societies
.