The ability to introduce and express foreign genes can greatly facilitate i
n vitro studies of the molecular biology of an organism. We report here the
first use of modified retroviral vectors to achieve foreign gene expressio
n in primary cultured cells from the Oka organ and ovary of the blue shrimp
Penaeus stylirostris (Litopenaeus) stylirostris (Holthuis 1980). Of the he
terologous promoters tested, the Moloney murine leukemia virus and Rous sar
coma virus promoters mediated the highest levels of reporter gene expressio
n. Firefly luciferase and Escherichia coli beta -galactosidase were success
fully used as reporter genes in cultured cells from both Oka organ and ovar
y. These in vitro systems can be exploited for the study of shrimp cellular
biology and regulation of gene expression.