EFFICIENT ISOLATION OF NOVEL MOUSE GENES DIFFERENTIALLY EXPRESSED IN EARLY POSTIMPLANTATION EMBRYOS

Most genes with regulatory functions in embryogenesis are expressed in highly specific patterns, suggesting that expression patterns can ser ve as criteria to define potential candidates for developmentally rele vant genes. To isolate such genes, we selected and partially sequenced 80 cDNA clones from a 10.5-day mouse embryo Library. Forty-one clones that represented novel mouse genes were analyzed for expression in em bryos of the same stage by whole-mount in situ hybridization. A high p roportion (24%) of these genes, including a homologue of the Drosophil a Delta gene, were expressed in specific spatially restricted patterns , suggesting that selection based on expression patterns is a useful s trategy to isolate novel genes that may play pivotal roles in mammalia n development. (C) 1995 Academic Press, Inc.