title: Nucleotide sequence and expression of relaxin-like gonad-stimulating peptide gene in starfish Asterina pectinifera.
abstract: Starfish gonad-stimulating substance (GSS) is the only known invertebrate peptide hormone responsible for final gamete maturation, rendering it functionally analogous to gonadotropins in vertebrates. Because GSS belongs to the relaxin-like peptide family, we propose renaming for starfish gonadotropic hormone as relaxin-like gonad-stimulating peptide (RGP). This study examined the primary structure and expression regulation of the RGP gene in starfish Asterina pectinifera. RGP consisted of 3896 base pairs (bp) divided over two exons, exon 1 of 208 bp and exon 2 of 2277 bp, and one intron of 1411 bp. Promoter sequences, CAAT and TATA boxes, were present in the 5'-upstream region of the coding DNA sequence of RGP. The transcript was 2485 bases (b) in length. The AAUAAA polyadenylation signal was found in 3'-untranslated region over 2kb away from the stop codon. This showed that only 14% of the RGP mRNA was translated into the peptide, because a size of the open-reading frame was 351 b. Furthermore, an analysis by using real-time quantitative PCR with specific primers for RGP showed that mRNA of RGP was expressed at high levels in the radial nerves. Expression was also observed in the cardiac stomachs, although the level was low, and trace levels were detected in the gonads, pyloric caeca and tube feet. This result suggests that the RGP gene is transcribed mainly in the radial nerves of A. pectinifera.
authors.affiliation: Department of Biology, Faculty of Education, Tokyo Gakugei University, Nukuikita-machi 4-1-1, Koganei-shi, Tokyo 184-8501, Japan; Laboratory of Integrative Brain Sciences, Department of Biology and Center for Medical Life Science, Waseda University, Wakamatsucho 2-2, Shinjuku-ku, Tokyo 162-8480, Japan.
authors.forename: Shogo
authors.initials: S
authors.lastname: Haraguchi
authors.affiliation: Department of Biology, Faculty of Education, Tokyo Gakugei University, Nukuikita-machi 4-1-1, Koganei-shi, Tokyo 184-8501, Japan.
authors.forename: Narumi
authors.initials: N
authors.lastname: Ikeda
authors.affiliation: Department of Biology, Faculty of Education, Tokyo Gakugei University, Nukuikita-machi 4-1-1, Koganei-shi, Tokyo 184-8501, Japan.
authors.forename: Michiko
authors.initials: M
authors.lastname: Abe
authors.affiliation: Laboratory of Integrative Brain Sciences, Department of Biology and Center for Medical Life Science, Waseda University, Wakamatsucho 2-2, Shinjuku-ku, Tokyo 162-8480, Japan.
authors.forename: Kazuyoshi
authors.initials: K
authors.lastname: Tsutsui
authors.affiliation: Department of Biology, Faculty of Education, Tokyo Gakugei University, Nukuikita-machi 4-1-1, Koganei-shi, Tokyo 184-8501, Japan. Electronic address: bio-mita@u-gakugei.ac.jp.
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Mita
mesh_terms: D000818:Animals; D047288:Asterina / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D006066:Gonads / Q000378:metabolism*; D007447:Invertebrate Hormones / Q000235:genetics / Q000378:metabolism*; D009479:Neuropeptides / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012065:Relaxin / Q000235:genetics / Q000378:metabolism*
chemical_list: C425158:GSS protein, Asteroidea; D007447:Invertebrate Hormones; D009479:Neuropeptides; D012333:RNA, Messenger; D012065:Relaxin
keywords: Coding-DNA sequence; Gene; Relaxin-like gonad-stimulating peptide (RGP); Starfish; Transcription