RNA interference screen to identify genes required for Drosophila embryonic nervous system development.

RNA interference (RNAi) has been shown to be a powerful method to study the function of genes in vivo by silencing endogenous mRNA with double-stranded (ds) RNA. Previously, we performed in vivo RNAi screening and identified 43 Drosophila genes, including 18 novel genes required for the development of the embryonic nervous system. In the present study, 22 additional genes affecting embryonic nervous system development were found.

Genes required for Drosophila nervous system development identified by RNA interference.

RNA interference was used to screen 3,314 Drosophila double-stranded RNAs, corresponding to approximately 25% of Drosophila genes, for genes that affect the development of the embryonic nervous system. RNA-interference-mediated gene silencing in Drosophila embryos resulted in loss-of-function mutant phenotypes for 43 genes, which is 1.3% of the genes that were screened.

Identification of Hedgehog pathway components by RNAi in Drosophila cultured cells.

Classical genetic screens can be limited by the selectivity of mutational targeting, the complexities of anatomically based phenotypic analysis, or difficulties in subsequent gene identification. Focusing on signaling response to the secreted morphogen Hedgehog (Hh), we used RNA interference (RNAi) and a quantitative cultured cell assay to systematically screen functional roles of all kinases and phosphatases, and subsequently 43% of predicted Drosophila genes. Two gene products reported to function in Wingless (Wg) signaling were identified as Hh pathway components: a cell surface protein (Dally-like protein) required for Hh signal reception, and casein kinase 1alpha, a candidate tumor suppressor that regulates basal activities of both Hh and Wg pathways.

Mouse Sebox homeobox gene expression in skin, brain, oocytes, and two-cell embryos.

Sebox is a mouse paired-like homeobox gene, previously named OG-9. Sebox genomic DNA and cDNA were cloned and sequenced. In addition, rat and human Sebox genomic DNAs were cloned and sequenced, and the predicted amino acid sequences were compared.

The mouse Nkx-1.2 homeobox gene: alternative RNA splicing at canonical and noncanonical splice sites.

A mouse homeobox gene, Nkx-1.2, (previously termed Sax-1) that is closely related to the Drosophila NK-1/S59 gene was cloned, and genomic DNA and cDNA were sequenced. Nine Nkx-1.