Expression from two Drosophila promoters in embryos of the migratory locust

We have accomplished gene transfer into embryos of Locusta migratoria, the African migratory locust. Freshly oviposited eggs were injected with circular or linear plasmids containing the Drosophila hsp70 promoter and the choramphenicol acetyltransferase (CAT) reporter gene (hsp-cat), or with circular plasmid containing the Drosophila copia promoter fused to CAT (copia-cat). Southern blot analysis showed that the hsp-cat plasmid persisted extrachromosomally for at least 8 days after injection. There was no evidence for plasmid replication. Transient expression from the introduced promoters was determined by monitoring CAT enzyme activity. After injection of hsp-cat, activity was detected at varying levels in 6–8% of day 3 and day 9 embryos. Embryos injected with copia-cat, assayed on day 3, had a greater frequency but no higher level of expression. The described gene transfer system is promising for analysis of other promoters, including those of Locusta.