title: Retroviral-like element in a marine invertebrate.
abstract: Retroviral-like elements (RL elements) include retroviruses and long terminal repeat (LTR)-containing retrotransposons. We report the presence of sea urchin RL elements (termed SURL) in eight species of sea urchins and find that these RL elements belong to several subfamilies. The complete DNA sequence of one SURL element in Tripneustes gratilla is 5266 base pairs long, including 254-nucleotide-long identical long terminal repeats (LTRs). It contains a single open reading frame nearly 4 kilobases long including the gag and pol genes. Comparison of conserved DNA sequences of RL elements from different sea urchin species indicates that active elements have been inserting copies into echinoid genomes for at least 200 million years.
authors.affiliation: Division of Biology, California Institute of Technology, Pasadena 91125.
authors.forename: M S
authors.initials: MS
authors.lastname: Springer
authors.forename: E H
authors.initials: EH
authors.lastname: Davidson
authors.forename: R J
authors.initials: RJ
authors.lastname: Britten
mesh_terms: D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D004254:DNA Nucleotidyltransferases / Q000235:genetics; D004251:DNA Transposable Elements; D005796:Genes; D019426:Integrases; D008969:Molecular Sequence Data; D012194:RNA-Directed DNA Polymerase / Q000235:genetics; D012091:Repetitive Sequences, Nucleic Acid; D012617:Sea Urchins / Q000235:genetics*; D016415:Sequence Alignment
chemical_list: D004251:DNA Transposable Elements; D004254:DNA Nucleotidyltransferases; D019426:Integrases; D012194:RNA-Directed DNA Polymerase