A 7-kb genomic segment containing the coding sequence for the Drosophila melanogaster Formosa variant of salivary gland secretion protein 3 (sgs3) has been inserted into the snw y, bw, st strain of D. melanogaster using the P transformation vector p.6.1. The inserted sequence codes for a shorter RNA which can be distinguished from that of the host gene. The amount of RNA, and its stage- and tissue-specific synthesis is identical to that of the host gene, which suggests that all the cis-acting regulatory DNA sequences for this gene are contained within this 7-kb segment.
