Dribble, the Drosophila KRR1p homologue, is involved in rRNA processing

The Drosophila dribble (dbe) gene encodes a KH domain protein, homologous t o yeast KRR1p. Expression of dbe transcripts is ubiquitous during embryogen esis. Overexpressed Dribble protein is localized in the nucleus and in some cell types in a subregion of the nucleolus. Homozygous dbe mutants die at first instar larval stage. Clonal analyses suggest that dbe(+) is required for survival of dividing cells. In dbe mutants, a novel rRNA-processing def ect is found and accumulation of an abnormal rRNA precursor is detected.