Abstract We isolated and characterized the tilapia (Oreochromis
mossambicus) HSP70 gene, highly homologous to other
HSP70 genes. A dramatic increase of tilapia HSP70 mRNA
levels was observed after heat shock of whole animals in all
organs tested. Reporter constructs were tested for transient
expression in carp cells and in microinjected zebrafish embryos.
The entire isolated regulatory region (3851/+157) was able to
mediate heat shock inducible expression of the reporter gene,
with no preference for a particular tissue. Our studies represent
the first transcriptional analysis of a HSP70 promoter from fish,
revealing a powerful tool to direct controlled, tissue-independent
gene expression in fish.