title: Molecular characterization of methoprene-tolerant gene (Met) in the swimming crab Portunus trituberculatus: Its putative role in methyl farnesoate-mediated vitellogenin transcriptional activation.
abstract: Methoprene-tolerant (Met) belongs to the basic helix-loop-helix (bHLH)-Per-Arnt-Sim (PAS) family of nuclear transcriptional regulators, and is the leading candidate receptor for the insect Juvenile hormone (JH) and the crustacean methyl farnesoate (MF). In the present study, a full-length cDNA of Met was cloned from the swimming crab, Portunus trituberculatus (PtMet). The PtMet amino acid sequence was found to contain domains characteristic of the bHLH-PAS family proteins and to have several conserved amino acid residues specifically responsible for JH or MF binding. In addition to its extensive tissue expression, PtMet mRNA is highly expressed in the female hepatopancreas, the primary site of vitellogenin (Vg) synthesis in P. trituberculatus. PtMet expression was significantly increased in the early-vitellogenic stage of ovarian development, which indicated that likely involvement in vitellogenesis regulation. In vitro, MF induced up-regulation of PtMet and PtVg expression in the hepatopancreas, but not in the ovary. In vivo, MF induced PtMet and PtVg expression in the hepatopancreas,and only PtMet expression was induced in the ovary. Taken together, these results suggest that Met can potentially serve as a MF receptor in crustaceans. In addition, the binding of Met to MF might transcriptionally regulate Vg synthesis in the hepatopancreas.
authors.affiliation: Key laboratory of Applied Marine Biotechnology of Ministry of Education, Ningbo University, Ningbo 315211, China.
authors.forename: Mingxin
authors.initials: M
authors.lastname: Liu
authors.affiliation: Key laboratory of Applied Marine Biotechnology of Ministry of Education, Ningbo University, Ningbo 315211, China.
authors.forename: Xi
authors.initials: X
authors.lastname: Xie
authors.affiliation: Key laboratory of Applied Marine Biotechnology of Ministry of Education, Ningbo University, Ningbo 315211, China.
authors.forename: Tian
authors.initials: T
authors.lastname: Tao
authors.affiliation: Key laboratory of Applied Marine Biotechnology of Ministry of Education, Ningbo University, Ningbo 315211, China.
authors.forename: Qinghua
authors.initials: Q
authors.lastname: Jiang
authors.affiliation: Key laboratory of Applied Marine Biotechnology of Ministry of Education, Ningbo University, Ningbo 315211, China.
authors.forename: Juan
authors.initials: J
authors.lastname: Shao
authors.affiliation: Key laboratory of Applied Marine Biotechnology of Ministry of Education, Ningbo University, Ningbo 315211, China. Electronic address: zhudongfa@nbu.edu.cn.
authors.forename: Dongfa
authors.initials: D
authors.lastname: Zhu
mesh_terms: D000818:Animals; D003386:Brachyura / Q000502:physiology*; D005231:Fatty Acids, Unsaturated / Q000378:metabolism*; D005260:Female; D005786:Gene Expression Regulation / Q000502:physiology*; D012313:RNA / Q000235:genetics / Q000378:metabolism; D014819:Vitellogenins / Q000235:genetics / Q000378:metabolism*
chemical_list: D005231:Fatty Acids, Unsaturated; D014819:Vitellogenins; C032429:methyl farnesoate; D012313:RNA
keywords: Gene expression; Methoprene-tolerant; Methyl farnesoate; Portunus trituberculatus; Vitellogenin