The Drosophila homolog of the immunoglobulin recombination signal-binding protein regulates peripheral nervous system development

Abstract

The J κ RBP binds to the immunoglobulin recombination signal sequence flanking the κ-type J segment. We previously Isolated the highly conserved homolog of the J κ RBP gene from D. melanogaster, which is not thought to have immunoglobulin molecules. Using many deficiency mutants and in situ hybridization, we mapped the Drosophila J κ RBP gene in a region containing two recessive lethal mutations, i.e., br26 and br7, which shows the dominant Suppressor of Hairless (Su(H)) phenotype in heterozygotes. All six Su(H) alleles analyzed at the DNA level contained mutations in the Drosophila J κ RBP gene. Since the Su(H) mutation affects peripheral nervous system development, the Drosophila J κ RBP gene product is involved in gene regulation of peripheral nervous system development. The results also imply that the immunoglobulin recombination signal sequence and the target sequence of the Drosophila J κ RBP protein might have a common evolutionary origin.