title: An insulin-like androgenic gland hormone gene in the mud crab, Scylla paramamosain, extensively expressed and involved in the processes of growth and female reproduction.
abstract: Insulin-like androgenic gland hormone (IAG) produced by androgenic gland (AG) in male crustaceans is regarded as a key regulator of sex differentiation. As a member of the insulin/insulin-like growth factor family, IAG is also likely involved in regulating somatic growth. In this study, a full-length cDNA of IAG (termed Sp-IAG) was isolated from the mud crab, Scylla paramamosain. Genomic DNA of Sp-IAG was also cloned, analysis of which reveals that Sp-IAG gene is organized in a 4 exon/3 intron manner. RNA in situ hybridization analysis detected positive signals in both type I and type II AG cells. Reverse transcription-polymerase chain reaction (RT-PCR) analysis showed that Sp-IAG was expressed not only in AG, but also in many other tissues. Sp-IAG expression levels in ovaries were examined at different stages of ovarian development (stages I to V); it was found that the expression was maintained at low levels during undeveloped stage (stage I) to late vitellogenic stage (stage IV) and then increased significantly at mature stage (stage V), suggesting that Sp-IAG may participate in inhibiting oocyte growth and vitellogenesis. The expression pattern of Sp-IAG during the molting cycle of the first stage crabs (C1) was also determined. Sp-IAG expression level continuously decreased from 0 h C1 (postmolt) crabs to 96 h C1 (premolt) crabs, and then increased significantly in the newly molted second stage crabs (C2, postmolt). The combined results suggested for the first time that IAG is involved in regulating ovarian development and somatic growth in crustaceans.
authors.affiliation: College of Ocean and Earth Sciences, Xiamen University, Xiamen 361005, China.
authors.forename: Xiaoshuai
authors.initials: X
authors.lastname: Huang
authors.affiliation: College of Ocean and Earth Sciences, Xiamen University, Xiamen 361005, China. Electronic address: haihuiye@xmu.edu.cn.
authors.forename: Haihui
authors.initials: H
authors.lastname: Ye
authors.affiliation: Center for Marine Biotechnology, Xiamen University, Xiamen 361005, China. Electronic address: huiyang@xmu.edu.cn.
authors.forename: Huiyang
authors.initials: H
authors.lastname: Huang
authors.affiliation: College of Ocean and Earth Sciences, Xiamen University, Xiamen 361005, China.
authors.forename: Yanan
authors.initials: Y
authors.lastname: Yang
authors.affiliation: College of Ocean and Earth Sciences, Xiamen University, Xiamen 361005, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Gong
mesh_terms: D000595:Amino Acid Sequence; D000728:Androgens / Q000378:metabolism*; D000818:Animals; D003386:Brachyura / Q000235:genetics*; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D005088:Exocrine Glands / Q000378:metabolism; D005260:Female; D017403:In Situ Hybridization; D007328:Insulin / Q000235:genetics*; D007447:Invertebrate Hormones / Q000235:genetics*; D008297:Male; D008969:Molecular Sequence Data; D009866:Oogenesis / Q000235:genetics; D010053:Ovary / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid; D012733:Sex Differentiation / Q000235:genetics; D014818:Vitellogenesis / Q000502:physiology
chemical_list: D000728:Androgens; D018076:DNA, Complementary; D007328:Insulin; D007447:Invertebrate Hormones; D012333:RNA, Messenger
keywords: Androgenic gland; Insulin/insulin-like growth factor family; Molting cycle; Ovarian development; Scylla paramamosain