RNA recognition motif (RRM)-containing proteins in Bombyx mori

Abstract

RNA recognition motif (RRM)-containing proteins play important roles in the processing of RNA and regulation of protein synthesis. Bombyx mori is a model species of Lepidoptera whose genome sequence is available; however, its RRM-containing proteins have not been thoroughly analyzed. In this study, 134 RRM-containing protein genes in Drosophila melanogaster were used to perform BLAST search against B. mori genome- and EST databases. Results showed that 123 genes have orthologues in the B. mori genome database and 89 in B. mori EST database, indicating some of the genes were not expressed in B. mori. 23 RRM-containing protein genes that have complete open reading frame were obtained through contig assembly in B. mori EST database and then registered in NCBI. Cluster analysis showed that these 23 new proteins formed two distinct clades. Especially, TAR DNA-binding
protein-43(TBPH) gene of B. mori is different from that of other species in that it does not have introns. Moreover, the length of TBPH of B. mori is much shorter than that of other species’ TBPH, suggesting
that it may play some roles in emergency responses.