ABSTRACT
Feminization-1 homolog b (Fem1b) is one of the genes essential for male development and play central roles in sex determination of Caenorhabditis elegans. In this study, we cloned and characterized the full-length Fem1b cDNA from the freshwater prawn Macrobrachium nipponense (MnFem1b) in different tissues and at different developmental stages. Real-time quantitative reverse polymerase chain reaction (RT-qPCR) showed that the MnFem1b gene was expressed in all investigated tissues, with the highest expression level found in the testes. The results revealed that the MnFem1b gene might play roles in aspects of development of the male prawn phenotype. The RT-qPCR also revealed that MnFem1b mRNA expression was significantly increased at 10 days after metamorphosis. The expression levels in all investigated tissues showed a certain degree of sexually dimorphism, the expression levels in males were significantly higher than those in females (P < 0.05). Notably, the highest expression of MnFem1b was found in the testes. The expression of MnFem1b in different tissues indicates that it plays multiple biological functions in M. nipponense.
Subject(s)
Androgen-Insensitivity Syndrome/genetics , Arthropod Proteins/genetics , Metamorphosis, Biological/genetics , Palaemonidae/genetics , Sex Determination Processes , Amino Acid Sequence/genetics , Animals , Caenorhabditis elegans/genetics , Cloning, Molecular , DNA, Complementary/genetics , Female , Gene Expression Regulation, Developmental , Male , Ovary/growth & development , Ovary/metabolism , Palaemonidae/growth & development , Phylogeny , RNA, Messenger/biosynthesis , RNA, Messenger/geneticsABSTRACT
Increasing evidence suggests that the insulin-like androgenic gland hormone (IAG) gene plays an important role in male sexual differentiation, metabolism, and growth in crustaceans. In the present study, we isolated the full-length genome sequence of IAG by genome walking based on the cDNA sequence in Macrobrachium nipponense. Four novel single nucleotide polymorphisms (SNPs) were studied, including 509G>T, 529G>T, 590A>T in intron 1, and 2226A>G in intron 2. The association of genetic variation with growth traits [body length (BL) and body weight (BW)] was analyzed. Individuals with GG geno- type at locus 2226A>G maintained higher mean BL (P < 0.01) and BW (P < 0.05) than AA and GA individuals. These results suggest that IAG SNPs may be useful molecular markers for selecting growth traits in M. nipponense.
Subject(s)
Genetic Association Studies , Gonadal Hormones/genetics , Sex Differentiation/genetics , Androgens/genetics , Androgens/metabolism , Animals , Cloning, Molecular , Gene Expression Regulation, Developmental , Gonadal Hormones/biosynthesis , Insulin/genetics , Insulin/metabolism , Male , Palaemonidae/genetics , Palaemonidae/growth & development , Polymorphism, Single NucleotideABSTRACT
A serotyping system for Vibrio cholerae non-OI was reported in this paper. With this typing system, 549 strains isolated from Guangdong province, Fujian province and Henan province were typed. The 55 serotypes were found in these strains. Among this, the dominant types were VBO 2, 7 and 9. The distribution of serotypes related with the different region. In our experiment, 19 serotypes were new types, different from sakazaki or smith strains. 83.79% tested strains can be typed with this VBO serotyping system.
