title: Molecular characterization of a novel ovary-specific gene fem-1 homolog from the oriental river prawn, Macrobrachium nipponense.
abstract: The feminization-1 (fem-1) gene is characterized by one of the most common protein-protein interaction motifs, ankyrin repeat motifs, displays many expression patterns in vertebrates and invertebrates, and plays an essential role in the sex-determination/differentiation pathway in Caenorhabditis elegans. In this study, a fem-1 homolog, designated as Mnfem-1, was first cloned from the oriental river prawn Macrobrachium nipponense. The prawn Mnfem-1 gene consists of six exons and five introns. The full-length cDNA (2603bp) of Mnfem-1 contains an open reading frame (ORF) encoding a protein of 622 amino acids. The Mnfem-1 RNA and protein are exclusively expressed in the ovary in adult prawns as revealed by RT-PCR and immunofluorescence analysis, respectively. In situ hybridization results showed that strong positive signals were concentrated at the edge of the previtellogenic and vitellogenic oocyte. During embryogenesis, Mnfem-1 is highly expressed in both unfertilized eggs and embryos at cleavage stage and thereafter dropped to a low level from blastula to zoea, indicating that the Mnfem-1 in early embryos is maternal. After hatching, the Mnfem-1 expression significantly increased in the larvae at length of 2cm, an important stage of sex differentiation. Yeast two hybridization results showed that the Mnfem-1 protein can be potentially interactive with cathepsin L and proteins containing the domains of insulinase, ankyrin or ubiquitin. Our results suggested that Mnfem-1 could have roles in prawn ovarian development and sex determination/differentiation.
authors.affiliation: Key Laboratory of Freshwater Aquatic Genetic Resources Certificated by Ministry of Agriculture, College of Fisheries and Life Science, Shanghai Ocean University, Shanghai 201306, PR China.
authors.forename: Ke-Yi
authors.initials: KY
authors.lastname: Ma
authors.affiliation: Key Laboratory of Freshwater Aquatic Genetic Resources Certificated by Ministry of Agriculture, College of Fisheries and Life Science, Shanghai Ocean University, Shanghai 201306, PR China.
authors.forename: Zhi-Qiang
authors.initials: ZQ
authors.lastname: Liu
authors.affiliation: Key Laboratory of Freshwater Aquatic Genetic Resources Certificated by Ministry of Agriculture, College of Fisheries and Life Science, Shanghai Ocean University, Shanghai 201306, PR China.
authors.forename: Jing-Yun
authors.initials: JY
authors.lastname: Lin
authors.affiliation: Key Laboratory of Freshwater Aquatic Genetic Resources Certificated by Ministry of Agriculture, College of Fisheries and Life Science, Shanghai Ocean University, Shanghai 201306, PR China; E-Institute of Shanghai Universities, Shanghai Ocean University, Shanghai 201306, PR China. Electronic address: jlli@shou.edu.cn.
authors.forename: Jia-Le
authors.initials: JL
authors.lastname: Li
authors.affiliation: Key Laboratory of Freshwater Aquatic Genetic Resources Certificated by Ministry of Agriculture, College of Fisheries and Life Science, Shanghai Ocean University, Shanghai 201306, PR China; E-Institute of Shanghai Universities, Shanghai Ocean University, Shanghai 201306, PR China. Electronic address: gfqiu@shou.edu.cn.
authors.forename: Gao-Feng
authors.initials: GF
authors.lastname: Qiu
mesh_terms: D000818:Animals; D060829:Arthropod Proteins / Q000235:genetics / Q000378:metabolism*; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism*; D005260:Female; D010053:Ovary / Q000254:growth & development*; D033541:Palaemonidae / Q000235:genetics / Q000378:metabolism*; D019849:Sex Determination Processes / Q000502:physiology*
chemical_list: D060829:Arthropod Proteins; D018797:Cell Cycle Proteins
keywords: Ankyrin; Crustaceans; Macrobrachium nipponense; Ovary; fem-1