Convergent origins and rapid evolution of spliced leader trans-splicing in metazoa: insights from the ctenophora and hydrozoa.

ABSTRACT: Replacement of mRNA 5' UTR sequences by short sequences trans-spliced from specialized, noncoding, spliced leader (SL) RNAs is an enigmatic phenomenon, occurring in a set of distantly related animal groups including urochordates, nematodes, flatworms, and hydra, as well as in Euglenozoa and dinoflagellates. Whether SL trans-splicing has a common evolutionary origin and biological function among different organisms remains unclear. We have undertaken a systematic identification of SL exons in cDNA sequence data sets from non-bilaterian metazoan species and their closest unicellular relatives. SL exons were identified in ctenophores and in hydrozoan cnidarians, but not in other cnidarians, placozoans, or sponges, or in animal unicellular relatives. Mapping of SL absence/presence obtained fro

SUBMITTER: Derelle R 

PROVIDER: S-EPMC2844618 | biostudies-literature | 2010 Apr

REPOSITORIES: biostudies-literature