Retroviral origins of theCaenorhabditis elegansorphan gene F58H7.5

Abstract

AbstractThis work describes the results of the genome-scale analysis of endogenous retrovirus insertions in twoC. elegansisolates: the prototype N2 (Bristol) and CB4856 (Hawaii). In total thirteen, identification of potentially replication competent, endogenous retroviral elements is described. Ten elements were identified as conserved between N2 and CB4856 by the reciprocal match of paired LTRs. The description focuses on the particular endogenous retrovirus insertion wich is identified on the proximal arm of the chromosome IV (located at positions IV: 912,948 – 921,658 and IV: 899,767 – 908,485 of the N2 and CB4856 respectively). In both isolates the inserted provirus is flanked by the predicted long terminal repeats (LTR)s of the length of 415 bp and of identical sequence. Provided the absolute LTR sequence identity this particular provirus represents insertion acquired prior to split from the common ancestor, suggesting this insertion event is evolutionary recent. The identified insertion of the endogenous retrovirus embeds the orphan gene F58H7.5, specific toC. eleganslineage. This unprecedented example establishes that in the evolutionary pastC. elegans, had acquired the gene of the retroviral origins presumably via mechanisms involving the RNA intermediate.ImportanceThis work describes the retroviral origins ofC. elegansorphan gene F58H7.5. Presented work implies that in the evolutionary past theC. eleganshave acquired new gene as a result of the infection event.C. elegansis presently regarded as genetic model organism widely used in genetic research. The genome ofC. eleganshave been sequenced nearly 20 years ago. This unprecedented example establishes that in the evolutionary past C. elegans genome, had acquired the gene of the retroviral origins presumably via mechanisms involving the RNA intermediate.