A set of X chromosome mutant stocks derived by insertional mutagenesis using the P-element construct P{lacW}; most lines have a lethal or semi-lethal phenotype. The P{lacW} construct carries a w+mC mini-white visible marker, Ecol\lacZ enhancer trap sequences, and bacterial sequences that allow plasmid rescue (FBrf0049800).
Insertion lines from this collection were assessed for inclusion in the Gene Disruption Project collection.
A genetic screen allowing selection of lethal or semi-lethal insertions on the X chromosome was carried out. Mobilization of the P{lacW} element occurred in males carrying a w[-] allele on the X chromosome, P{lacW} on the second chromosome and P{Δ2-3}99B, a stable source of P transposase, on a marked third chromosome. The selection scheme produced balanced stocks of X chromosome insertions; 501 lines that were hemizygously lethal or semi-lethal were established.
Markers in stocks (as originally submitted to the BDSC):w67c23.
Flanking genomic sequences for 496 lines were obtained by sequencing of plasmid rescued or inverse PCR products, and were mapped by alignment to the genomic sequence. The cytological insertion sites of 401 strains were determined by in situ hybridization on polytene chromosome squashes. These analyses indicated that >90% of the lines contained single insertions.
