Generation of a micro-RNA knockout using homologous recombination in Drosophila melanogaster Böhm U. L. and Cohen S.M

micro-RNAs are small, 21-24 nt long RNA molecues that regulate gene activity by binding specifically to the 3'-untranslated region of target messenger RNAs. micro-RNAs are believed to play important roles in controll and regulation of many cellular processes but for most of them very little is known about their concrete functions. Two micro-RNA genes, miR-314 and miR1014, were chosen to generate a gene knockout using 'ends-out' homologous recombination. Homologous recombination provides the possibility to specifically target a single gene and therefore makes it a valuable tool for any forward genetics approach. The results here describe the different steps of the method and show its successful application to one of the targeted genes. Recombination was observed with a frequency of $\sim$1 in 63 crosses. Furthermore this report describes the possibilities to use the knockout construct in subsequent expression analysis and to create a clean null allele of the knockout