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Francesc Piferrer - One of the best experts on this subject based on the ideXlab platform.

  • Gene expression analysis at the onset of Sex Differentiation in turbot (Scophthalmus maximus).
    BMC genomics, 2015
    Co-Authors: Diego Robledo, Francesc Piferrer, Laia Ribas, Rosa Cal, Laura Sánchez, Paulino Martínez, Ana Viñas
    Abstract:

    Controlling Sex ratios is essential for the aquaculture industry, especially in those species with Sex dimorphism for relevant productive traits, hence the importance of knowing how the Sexual phenotype is established in fish. Turbot, a very important fish for the aquaculture industry in Europe, shows one of the largest Sexual growth dimorphisms amongst marine cultured species, being all-female stocks a desirable goal for the industry. Although important knowledge has been achieved on the genetic basis of Sex determination (SD) in this species, the master SD gene remains unknown and precise information on gene expression at the critical stage of Sex Differentiation is lacking. In the present work, we examined the expression profiles of 29 relevant genes related to Sex Differentiation, from 60 up to 135 days post fertilization (dpf), when gonads are differentiating. We also considered the influence of three temperature regimes on Sex Differentiation. The first Sex-related differences in molecular markers could be observed at 90 days post fertilization (dpf) and so we have called that time the onset of Sex Differentiation. Three genes were the first to show differential expression between males and females and also allowed us to Sex turbot accurately at the onset of Sex Differentiation (90 dpf): cyp19a1a, amh and vasa. The expression of genes related to primordial germ cells (vasa, gsdf, tdrd1) started to increase between 75–90 dpf and vasa and tdrd1 later presented higher expression in females (90-105 dpf). Two genes placed on the SD region of turbot (sox2, fxr1) did not show any expression pattern suggestive of a Sex determining function. We also detected changes in the expression levels of several genes (ctnnb1, cyp11a, dmrt2 or sox6) depending on culture temperature. Our results enabled us to identify the first Sex-associated genetic cues (cyp19a1a, vasa and amh) at the initial stages of gonad development in turbot (90 dpf) and to accurately Sex turbot at this age, establishing the correspondence between gene expression profiles and histological Sex. Furthermore, we profiled several genes involved in Sex Differentiation and found specific temperature effects on their expression.

  • HORMONAL CONTROL OF REPRODUCTION AND GROWTH | Endocrine Control of Sex Differentiation in Fish
    Encyclopedia of Fish Physiology, 2011
    Co-Authors: Francesc Piferrer
    Abstract:

    Sex Differentiation is the development of an undifferentiated gonad and its transformation into either a testis or ovary. This produces the phenotypic Sex on an individual basis and the Sex ratio on a population basis. Sex Differentiation in fish is highly dependent on steroid hormones, the androgens and estrogens. These Sex steroids are synthesized by steroidogenic enzymes, among which aromatase plays a central role, and exert their actions through specific receptors. The genes involved are quite conserved across vertebrates. However, Sex Differentiation is particularly labile in fish and thus in many species this process can be affected by changes in the biotic or abiotic conditions.

  • fish gonadogenesis part ii molecular biology and genomics of Sex Differentiation
    Reviews in Fisheries Science, 2008
    Co-Authors: Francesc Piferrer, Yann Guiguen
    Abstract:

    The combined result of the mechanisms of Sex determination and Sex Differentiation is the Sex ratio of a population. Because Sex-related growth dimorphism in fish is quite common, Sex ratios influence population reproductive capacity and contribute to size variation and growth patterns before and after Sexual maturation. This may have practical consequences for aquaculture and explains the interest in Sex control to favor the Sex with superior growth, better food conversion efficiency, later Sexual maturation, or to prevent reproduction if both Sexes mature before harvest. This review concentrates on recent research using molecular biology tools to broaden our understanding of the different aspects related to fish Sex Differentiation, both in model fish species and economically important species. The contribution of genomics to this field is mainly through the use of microarrays for the analysis of the transcriptome, to identify expression signatures associated with the development of a particular phenoty...

  • Fish gonadogenesis. Part II: molecular biology and genomics of Sex Differentiation
    Reviews in Fisheries Science, 2008
    Co-Authors: Francesc Piferrer, Yann Guiguen
    Abstract:

    The combined result of the mechanisms of Sex determination and Sex Differentiation is the Sex ratio of a population. Because Sex-related growth dimorphism in fish is quite common, Sex ratios influence population reproductive capacity and contribute to size variation and growth patterns before and after Sexual maturation. This may have practical consequences for aquaculture and explains the interest in Sex control to favor the Sex with superior growth, better food conversion efficiency, later Sexual maturation, or to prevent reproduction if both Sexes mature before harvest. This review concentrates on recent research using molecular biology tools to broaden our understanding of the different aspects related to fish Sex Differentiation, both in modal fish species and economically important species. The contribution of genomics to this field is mainly through the use of microarrays for the analysis of the transcriptome, to identify expression signatures associated with the development of a particular phenotype, or genes involved in the process of Sex Differentiation, both under normal conditions and after exposure to a particular natural or aquaculture environment.

Yann Guiguen - One of the best experts on this subject based on the ideXlab platform.

  • The Tambaqui (Colossoma macropomum) transcriptome at Sex Differentiation stage
    2018
    Co-Authors: I. Lobo, Yann Guiguen, A. Nascimento, M. Yamagishi, G.f. Silva, F.l. Almeida
    Abstract:

    The Tambaqui (Colossoma macropomum) transcriptome at Sex Differentiation stage. 11. International Symposium on Reproductive Physiology of Fish

  • fish gonadogenesis part ii molecular biology and genomics of Sex Differentiation
    Reviews in Fisheries Science, 2008
    Co-Authors: Francesc Piferrer, Yann Guiguen
    Abstract:

    The combined result of the mechanisms of Sex determination and Sex Differentiation is the Sex ratio of a population. Because Sex-related growth dimorphism in fish is quite common, Sex ratios influence population reproductive capacity and contribute to size variation and growth patterns before and after Sexual maturation. This may have practical consequences for aquaculture and explains the interest in Sex control to favor the Sex with superior growth, better food conversion efficiency, later Sexual maturation, or to prevent reproduction if both Sexes mature before harvest. This review concentrates on recent research using molecular biology tools to broaden our understanding of the different aspects related to fish Sex Differentiation, both in model fish species and economically important species. The contribution of genomics to this field is mainly through the use of microarrays for the analysis of the transcriptome, to identify expression signatures associated with the development of a particular phenoty...

  • Fish gonadogenesis. Part II: molecular biology and genomics of Sex Differentiation
    Reviews in Fisheries Science, 2008
    Co-Authors: Francesc Piferrer, Yann Guiguen
    Abstract:

    The combined result of the mechanisms of Sex determination and Sex Differentiation is the Sex ratio of a population. Because Sex-related growth dimorphism in fish is quite common, Sex ratios influence population reproductive capacity and contribute to size variation and growth patterns before and after Sexual maturation. This may have practical consequences for aquaculture and explains the interest in Sex control to favor the Sex with superior growth, better food conversion efficiency, later Sexual maturation, or to prevent reproduction if both Sexes mature before harvest. This review concentrates on recent research using molecular biology tools to broaden our understanding of the different aspects related to fish Sex Differentiation, both in modal fish species and economically important species. The contribution of genomics to this field is mainly through the use of microarrays for the analysis of the transcriptome, to identify expression signatures associated with the development of a particular phenotype, or genes involved in the process of Sex Differentiation, both under normal conditions and after exposure to a particular natural or aquaculture environment.

  • Endocrine and environmental aspects of Sex Differentiation in gonochoristic fish.
    EXS, 2001
    Co-Authors: Jean-françois Baroiller, Yann Guiguen
    Abstract:

    This paper reviews current knowledge concerning the endocrine and environmental regulation of gonadal Sex Differentiation in gonochoristic fish. In gonochoristic fish, although potentially active around this period, the hypothalamo-pituitary axis is probably not involved in triggering Sex Differentiation. Although steroids and steroidogenic enzymes are probably not the initial triggers of Sex Differentiation, new data, including molecular approaches, have confirmed that they are key physiological steps in the regulation of this process. Environmental factors can strongly influence Sex Differentiation in gonochoristic fish. The most important environmental determinant of Sex would appear to be temperature. Interactions between environmental factors and genotype have been suggested for gonochoristic fish.

  • Implication of steroids in fish gonadal Sex Differentiation and Sex inversion
    Current Topics in Steroid Research, 2000
    Co-Authors: Yann Guiguen
    Abstract:

    This paper reviews the current knowledge concerning the implication of steroid hormones in both gonadal Sex Differentiation in gonochoristic fish and gonadal Sex inversion in hermaphroditic fish. Although steroids and steroidogenic enzymes are probably not the initial triggers of gonadal Sex Differentiation or gonadal Sex-inversion, new data, including molecular approaches, confirm that they are key physiological steps in the regulation of these processes. The importance of estrogens in fish gonadal Differentiation is now more and more documented, and aromatase is probably one of the key enzymes needed for both ovarian Differentiation in gonochoristic fish and for Sex inversion in hermaphroditic fish. However, the implication of 11-oxygenated androgens in fish Sex Differentiation or Sex inversion also deserve attention and we hypothesise that the balance between gonadal 11-oxygenated androgens and estrogens would directed either male (excess of androgens) or female (excess of estrogens) gonadal Sex Differentiation.

Takeshi Kitano - One of the best experts on this subject based on the ideXlab platform.

  • Endocrine and Environmental Control of Sex Differentiation in Gonochoristic Fish
    Diversity and Commonality in Animals, 2018
    Co-Authors: Takeshi Kitano
    Abstract:

    Sex in vertebrates, including fish, is usually determined by genotype. In medaka (Oryzias latipes), a gonochoristic fish with the XX/XY Sex determination system, a gene that encodes the DM domain on the Y chromosome is identified as the master Sex-determining gene. However, the Sex-determining genes in many nonmammalian vertebrates remain unclarified. In contrast, Sex determination in some reptiles, amphibians, and fish is influenced greatly by environmental factors. For example, although the genotypic Sex determination mechanism in Japanese flounder (Paralichthys olivaceus) is basically the XX/XY type, genotypic females can be Sex reversed to phenotypic males by rearing the larvae at high or low water temperatures during gonadal Sex Differentiation. In addition, the phenotypic Sex of many teleost fish, including flounder, can be experimentally altered by treatment with Sex steroid hormones, suggesting an important role for Sex steroid hormones in gonadal Sex Differentiation in fish. In this chapter, we review general information and recent knowledge on the basic mechanisms of Sex determination and gonadal Sex Differentiation, and present the effects of Sex steroid hormones and water temperature on gonadal Sex Differentiation in gonochoristic fish.

  • Mechanism of gonadal Sex Differentiation in Japanese flounder (Paralichthys olivaceus)
    2006
    Co-Authors: Takeshi Kitano
    Abstract:

    * Abstract Japanese flounder (Paralichthys olivaceus) is a teleost fish which has a XX (female)/XY (male) Sex determination mechanism. Genetic females can be experimentally Sex-reversed to phenotypic males when the larvae are reared at high water temperature or treated with androgens, providing an excellent model to study mechanisms of gonadal Sex Differentiation in teleost fishes. In the present paper, I review recent findings on gonadal Sex Differentiation in Japanese flounder, and then discuss mainly about roles of Sex steroid hormones on the Sex differen- tiation.

  • Sexually dimorphic expression of a teleost homologue of mullerian inhibiting substance during gonadal Sex Differentiation in japanese flounder paralichthys olivaceus
    Biochemical and Biophysical Research Communications, 2004
    Co-Authors: Norifumi Yoshinaga, Eri Shiraishi, Takashi Yamamoto, Taisen Iguchi, Shin Ichi Abe, Takeshi Kitano
    Abstract:

    Mullerian inhibiting substance (MIS), also known as anti-Mullerian hormone, is a glycoprotein belonging to transforming growth factor beta superfamily. In mammals, MIS is responsible for regression of Mullerian ducts, anlagen of the female reproductive ducts, in the male fetus. However, the role of MIS in gonadal Sex Differentiation of teleost fishes, which do not have the Mullerian ducts, has yet to be clarified. To address the role of MIS on gonadal Sex Differentiation in fishes, we isolated a MIS cDNA from the Japanese flounder testis and examined the expression pattern of MIS mRNA in gonads of both Sexes during Sex Differentiation period. In this study, we present the first demonstration of Sexually dimorphic expression of MIS mRNA during Sex Differentiation in teleost fishes, similarly to amniote vertebrates which possess the Mullerian ducts.

Zhenmin Bao - One of the best experts on this subject based on the ideXlab platform.

  • FOXL2 and DMRT1L Are Yin and Yang Genes for Determining Timing of Sex Differentiation in the Bivalve Mollusk Patinopecten yessoensis
    Frontiers in physiology, 2018
    Co-Authors: Lingling Zhang, Yang Zhang, Meiwei Zhang, Liang Zhao, Shi Wang, Zhenmin Bao
    Abstract:

    Sex determination and Differentiation have long been a research hotspot in metazoans. However, little is known about when and how Sex Differentiation occurs in most mollusks. In this study, we conducted a combined morphological and molecular study on Sex Differentiation in the Yesso scallop Patinopecten yessoensis. Histological examination on gonads from 5- to 13-month-old juveniles revealed that the morphological Sex Differentiation occurred at 10 months of age. To determine the onset of molecular Sex Differentiation, molecular markers were screened for early identification of Sex. The gonadal expression profiles of eight candidate genes for Sex determination or Differentiation showed that only two genes displayed Sexually dimorphic expression, with FOXL2 being abundant in ovaries and DMRT1L in testes. In situ hybridization revealed that both of them were detected in germ cells and follicle cells. We therefore developed LOG10(DMRT1L/FOXL2) for scallop Sex identification and confirmed its feasibility in differentiated individuals. By tracing its changes in 5- to 13-month-old juveniles, molecular Sex Differentiation time was determined: some scallops differentiate early in September when they are 7 months old, and some do late in December when they are 10 months old. Two kinds of coexpression patterns were found between FOXL2 and DMRT1L: expected antagonism after Differentiation and unexpected coordination before Differentiation. Our results revealed that scallop Sex Differentiation co-occurs with the formation of follicles, and molecular Sex Differentiation is established prior to morphological Sex Differentiation. Our study will assist in a better understanding of the molecular mechanism underlying bivalve Sex Differentiation.

May Penrad-mobayed - One of the best experts on this subject based on the ideXlab platform.

  • Early aspects of gonadal Sex Differentiation inXenopus tropicalis with reference to an antero-posterior gradient
    Journal of Experimental Zoology Part A: Ecological Genetics and Physiology, 2008
    Co-Authors: Anwar El Jamil, Solange Magre, André Mazabraud, May Penrad-mobayed
    Abstract:

    International audienceIn an effort to contribute to the development of Xenopus tropicalis as an amphibian model system, we carried out a detailed histological analysis of the process of gonadal Sex Differentiation and were able to find evidence that gonadal Differentiation in X. tropicalis follows an antero-posterior gradient. Although the main reason for the presence of a gradient of Sex Differentiation is still unknown, this gradient enabled us to define the early events that signal ovarian and testicular Differentiation and to identify the undifferentiated gonad structure. Given the various advantages of this emerging model, our work paves the way for experiments that should contribute to our understanding of the dynamics and mechanisms of gonadal Sex Differentiation in amphibians. J. Exp. Zool. 309A, 2008. (c) 2008 Wiley-Liss, Inc

  • Early aspects of gonadal Sex Differentiation in Xenopus tropicalis with reference to an antero-posterior gradient.
    Journal of experimental zoology. Part A Ecological genetics and physiology, 2008
    Co-Authors: Anwar El Jamil, Solange Magre, André Mazabraud, May Penrad-mobayed
    Abstract:

    In an effort to contribute to the development of Xenopus tropicalis as an amphibian model system, we carried out a detailed histological analysis of the process of gonadal Sex Differentiation and were able to find evidence that gonadal Differentiation in X. tropicalis follows an antero-posterior gradient. Although the main reason for the presence of a gradient of Sex Differentiation is still unknown, this gradient enabled us to define the early events that signal ovarian and testicular Differentiation and to identify the undifferentiated gonad structure. Given the various advantages of this emerging model, our work paves the way for experiments that should contribute to our understanding of the dynamics and mechanisms of gonadal Sex Differentiation in amphibians.

  • Early aspects of gonadal Sex Differentiation in Xenopus tropicalis with reference to an antero-posterior gradient.
    Journal of Experimental Zoology Part A Ecological Genetics and Physiology, 2008
    Co-Authors: Anwar El Jamil, Solange Magre, André Mazabraud, May Penrad-mobayed
    Abstract:

    In an effort to contribute to the development of Xenopus tropicalis as an amphibian model system, we carried out a detailed histological analysis of the process of gonadal Sex Differentiation and were able to find evidence that gonadal Differentiation in X. tropicalis follows an antero-posterior gradient. Although the main reason for the presence of a gradient of Sex Differentiation is still unknown, this gradient enabled us to define the early events that signal ovarian and testicular Differentiation and to identify the undifferentiated gonad structure. Given the various advantages of this emerging model, our work paves the way for experiments that should contribute to our understanding of the dynamics and mechanisms of gonadal Sex Differentiation in amphibians. J. Exp. Zool. 309A, 2008. (c) 2008 Wiley-Liss, Inc.