Genetic organization of theci-M-panregion on chromosome IV inDrosophila melanogaster

Abstract

The genes cubitus interruptus (ci), ribosomal protein S3A (RpS3A), and pangolin (pan) are localized within 73 kb in the cytological region 101F-102A on chromosome IV in Drosophila melanogaster. A region of 13 kb harbours the regulatory regions of both ci and pan, transcribed in opposite directions, and a 1.1-kb gene encoding RpS3A. This dense clustering gives rise to very complicated complementation patterns between different alleles in these loci. We investigated this region genetically and molecularly by use of an enhancer trap line (IA5), where the P-element was found to be inserted into the first intron of pan. Screens for imprecise excisions of the P-element were performed, and complementations between new and old established mutant lines were investigated. We found that when mutated or deleted the RpS3A gene gives rise to a Minute phenotype, and we conclude that M(4)101 encodes the ribosomal protein S3A.

DrosophilaPlexin B is a Sema-2a receptor required for axon guidance

“…The KG00878 line was a generous gift from the P-element Screen/Gene Disruption Project (Bellen et al, 2004). Mutations on the fourth chromosome were identified in embryos by first crossing the lines to either of the following lacZ-containing genetic elements: l(4)P{lacW}IA5/ey D (Kronhamn and Rasmuson-Lestander, 1999), P{LacW}ci Dplac (Eaton and Kornberg, 1990), or P{lacZ}Pax2 ⌬122 (Hirth et al, 2003). The desired embryos were selected after an X-gal reaction was performed to detect ␤-galactosidase activity as described (Yu et al, 1998).…”