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Ching-fong Chang - One of the best experts on this subject based on the ideXlab platform.
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Robust gdf9 and bmp15 expression in the oocytes of ovotestes through the Figla-independent pathway in the hermaphroditic black porgy, Acanthopagrus schlegelii
2017Co-Authors: Jia-wun Luo, Chen-hsiu Huang, Ching-fong ChangAbstract:More than 1,500 fish species are hermaphroditic, but no hermaphroditic lineage appears to be evolutionarily ancient in fishes. Thus, whether more than one sex at a time was present during the evolutionary shift from Gonochorism to hermaphroditism in fishes is an intriguing question. Ectopic oocytes were created in the ovotestes of protandrous black porgy via the withdrawal of estradiol (E2) administration. These ectopic oocytes reprogrammed the surrounding cells, which changed from Sertoli cells to follicle-like cells. We observed that gdf9 and bmp15 expression was localized in the primary oocytes and gradually decreased after oocytes entered a secondary oocyte stage. Robust expression of gdf9 and bmp15 in ectopic oocytes was associated with the surrounding Sertoli cells. However, blocking Cyp19a1a activity and increasing androgen levels did not stimulate the expression of gdf9 and bmp15. Thus, the robust gdf9 and bmp15 expression was not related to the inappropriate male microenvironment. Furthermore, in vitro data demonstrated that gdf9 and bmp15 were not downstream genes of Figla signaling. Therefore, our results suggest that there are two independent mechanisms, a Figla-dependent pathway and a Figla-independent pathway, by which oocyte-surrounding cells are altered from a male somatic fate to a female somatic fate. This functional switch might clarify how oocytes created an appropriate microenvironment during the transition from the ancient Gonochorism to the present hermaphroditism.
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The Potential Role of Amh to Prevent Ectopic Female Development in Testicular Tissue of the Protandrous Black Porgy, Acanthopagrus schlegelii 1 Running Title: ECTOPIC FEMALE GROWTH IS ARRESTED BY Amh SIGNALING
2016Co-Authors: Jia-wun Luo, Chi Chen, Ching-fong ChangAbstract:In most vertebrates, hermaphroditism results in infertility. However, hermaphroditism occurs in 6 % of teleosts, which primarily undergo protogyny. Here, to elucidate the transient stage from Gonochorism to hermaphroditism, juvenile black porgies as a model animal were fed a diet containing estradiol (E2) for 3-mo, followed by withdrawal of E2 treatment. The E2-terminated fish had ectopically-located oocytes in the regenerated testes. anti-mullerian hormone (amh) was strongly expressed in the Sertoli cells with type A spermatogonia and follicle cells with vitellogenic oocytes. Amh was robustly expressed in the ectopic oocytes-bordering region of regenerated testes and in testes with non-synchronous spermatogenesis. This Amh was released by Sertoli cells and aggregated in the area containing type A spermatogonia in the ectopic oocytes-bordering region. Our in vitro results show that exogenous recombinant Amh (rAmh) can inhibit type A spermatogonia proliferation in the testis, but not oogonia proliferation in the ovary. We suggest that Amh-arrested spermatogonia A may act as a boundary to block inter-cellular communication (i.e., prevent peptide factors released from female tissue to alter the sexual fate of type A spermatogonia) and further inhibit female growth. These results suggest that black porgy can prevent ectopic femal
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the potential role of amh to prevent ectopic female development in testicular tissue of the protandrous black porgy acanthopagrus schlegelii
Biology of Reproduction, 2015Co-Authors: Jia-wun Luo, Chi Chen, Ching-fong ChangAbstract:In most vertebrates, hermaphroditism results in infertility. However, hermaphroditism occurs in 6% of teleosts, which primarily undergo protogyny. Here, to elucidate the transient stage from Gonochorism to hermaphroditism, juvenile black porgies as a model animal were fed a diet containing estradiol (E2) for 3 mo, followed by withdrawal of E2 treatment. The E2-terminated fish had ectopically located oocytes in the regenerated testes. Antimullerian hormone (amh) was strongly expressed in the Sertoli cells with type A spermatogonia and follicle cells with vitellogenic oocytes. Amh was robustly expressed in the ectopic oocytes-bordering region of regenerated testes and in testes with nonsynchronous spermatogenesis. This Amh was released by Sertoli cells and aggregated in the area containing type A spermatogonia in the ectopic oocytes-bordering region. Our in vitro results show that exogenous recombinant Amh (rAmh) can inhibit type A spermatogonia proliferation in the testis but not oogonia proliferation in the ovary. We suggest that Amh-arrested spermatogonia A may act as a boundary to block intercellular communication (i.e., prevent peptide factors released from female tissue to alter the sexual fate of type A spermatogonia) and further inhibit female growth. These results suggest that black porgy can prevent ectopic female growth in the testis and maintain male function of the digonic gonad (testes and ovary separated by the connective tissue) through Amh action. This function of amh might shed light on why the majority of syngonic fish undergo protogyny (female-to-male sex change).
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oocytes survive in the testis by altering the soma fate from male to female in the protandrous black porgy acanthopagrus schlegeli
Biology of Reproduction, 2013Co-Authors: Ching-fong ChangAbstract:In fish, hermaphroditism is derived from Gonochorism. No ancient ancestry and no single sex-determining mechanism are involved in the hermaphroditic fish. Furthermore, hermaphroditic fish have a common set of transcriptional regulators that are involved in gonadal differentiation. However, the origins and evolution of hermaphroditism in fish remain far from understood. In the protandrous black porgy (Acanthopagrus schlegeli Bleeker), the ovotestis is separated by connective tissue, and no intersex (ectopic germ cell) characteristics are observed in either part. We generated the abnormal testicular part of the ovotestis with estradiol-17beta (E2) treatment, in which newly regenerated testis has ectopic oocytes. In this study, we performed a detailed phenotypic and molecular analysis of these E2-induced ectopic oocytes in the testicular part of the ovotestis. We showed that the oocytes in the regenerated testis do not undergo apoptosis; thus, a number of oocytes are in the testis. In these oocytes, Figla has a prolonged expression with ectopic expression of Cyp19a1a. Strikingly, the cells surrounding the oocytes are Dmrt1-positive cells (putative Sertoli cells) with high Figla expression in the oocytes at an early stage. Then, as the Dmrt1 expression diminishes, Cyp19a1a-positive cells (putative follicle cells) with low Figla expression appear in the oocytes at a later stage. This finding indicates that oocytes are competent to create a microenvironment to protect against a testicular environment in black porgy fish. Furthermore, Figla likely is the key factor in the pathway of Sertoli cell transformation into follicle-like cells. These results shed light on why the presence of more than one sex at a time existed during an evolutionary transition from Gonochorism to hermaphroditism in fish.
Costas S Tsigenopoulos - One of the best experts on this subject based on the ideXlab platform.
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the sex specific transcriptome of the hermaphrodite sparid sharpsnout seabream diplodus puntazzo
BMC Genomics, 2014Co-Authors: Tereza Manousaki, Alexandros Tsakogiannis, Jacques Lagnel, Elena Sarropoulou, Jenny Xiang, Nikos Papandroulakis, Constantinos C Mylonas, Costas S TsigenopoulosAbstract:Teleosts are characterized by a remarkable breadth of sexual mechanisms including various forms of hermaphroditism. Sparidae is a fish family exhibiting Gonochorism or hermaphroditism even in closely related species. The sparid Diplodus puntazzo (sharpsnout seabream), exhibits rudimentary hermaphroditism characterized by intersexual immature gonads but single-sex mature ones. Apart from the intriguing reproductive biology, it is economically important with a continuously growing aquaculture in the Mediterranean Sea, but limited available genetic resources. Our aim was to characterize the expressed transcriptome of gonads and brains through RNA-Sequencing and explore the properties of genes that exhibit sex-biased expression profiles. Through RNA-Sequencing we obtained an assembled transcriptome of 82,331 loci. The expression analysis uncovered remarkable differences between male and female gonads, while male and female brains were almost identical. Focused search for known targets of sex determination and differentiation in vertebrates built the sex-specific expression profile of sharpsnout seabream. Finally, a thorough genetic marker discovery pipeline led to the retrieval of 85,189 SNPs and 29,076 microsatellites enriching the available genetic markers for this species. We obtained a nearly complete source of transcriptomic sequence as well as marker information for sharpsnout seabream, laying the ground for understanding the complex process of sex differentiation of this economically valuable species. The genes involved include known candidates from other vertebrate species, suggesting a conservation of the toolkit between gonochorists and hermaphrodites.
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The sex-specific transcriptome of the hermaphrodite sparid sharpsnout seabream (Diplodus puntazzo)
BMC Genomics, 2014Co-Authors: Tereza Manousaki, Alexandros Tsakogiannis, Jacques Lagnel, Elena Sarropoulou, Nikos Papandroulakis, Constantinos C Mylonas, Jenny Z. Xiang, Costas S TsigenopoulosAbstract:Background: Teleosts are characterized by a remarkable breadth of sexual mechanisms including various forms of hermaphroditism. Sparidae is a fish family exhibiting Gonochorism or hermaphroditism even in closely related species. The sparid Diplodus puntazzo (sharpsnout seabream), exhibits rudimentary hermaphroditism characterized by intersexual immature gonads but single-sex mature ones. Apart from the intriguing reproductive biology, it is economically important with a continuously growing aquaculture in the Mediterranean Sea, but limited available genetic resources. Our aim was to characterize the expressed transcriptome of gonads and brains through RNA-Sequencing and explore the properties of genes that exhibit sex-biased expression profiles. Results: Through RNA-Sequencing we obtained an assembled transcriptome of 82,331 loci. The expression analysis uncovered remarkable differences between male and female gonads, while male and female brains were almost identical. Focused search for known targets of sex determination and differentiation in vertebrates built the sex-specific expression profile of sharpsnout seabream. Finally, a thorough genetic marker discovery pipeline led to the retrieval of 85,189 SNPs and 29,076 microsatellites enriching the available genetic markers for this species. Conclusions: We obtained a nearly complete source of transcriptomic sequence as well as marker information for sharpsnout seabream, laying the ground for understanding the complex process of sex differentiation of this economically valuable species. The genes involved include known candidates from other vertebrate species, suggesting a conservation of the toolkit between gonochorists and hermaphrodites.
Tereza Manousaki - One of the best experts on this subject based on the ideXlab platform.
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the sex specific transcriptome of the hermaphrodite sparid sharpsnout seabream diplodus puntazzo
BMC Genomics, 2014Co-Authors: Tereza Manousaki, Alexandros Tsakogiannis, Jacques Lagnel, Elena Sarropoulou, Jenny Xiang, Nikos Papandroulakis, Constantinos C Mylonas, Costas S TsigenopoulosAbstract:Teleosts are characterized by a remarkable breadth of sexual mechanisms including various forms of hermaphroditism. Sparidae is a fish family exhibiting Gonochorism or hermaphroditism even in closely related species. The sparid Diplodus puntazzo (sharpsnout seabream), exhibits rudimentary hermaphroditism characterized by intersexual immature gonads but single-sex mature ones. Apart from the intriguing reproductive biology, it is economically important with a continuously growing aquaculture in the Mediterranean Sea, but limited available genetic resources. Our aim was to characterize the expressed transcriptome of gonads and brains through RNA-Sequencing and explore the properties of genes that exhibit sex-biased expression profiles. Through RNA-Sequencing we obtained an assembled transcriptome of 82,331 loci. The expression analysis uncovered remarkable differences between male and female gonads, while male and female brains were almost identical. Focused search for known targets of sex determination and differentiation in vertebrates built the sex-specific expression profile of sharpsnout seabream. Finally, a thorough genetic marker discovery pipeline led to the retrieval of 85,189 SNPs and 29,076 microsatellites enriching the available genetic markers for this species. We obtained a nearly complete source of transcriptomic sequence as well as marker information for sharpsnout seabream, laying the ground for understanding the complex process of sex differentiation of this economically valuable species. The genes involved include known candidates from other vertebrate species, suggesting a conservation of the toolkit between gonochorists and hermaphrodites.
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The sex-specific transcriptome of the hermaphrodite sparid sharpsnout seabream (Diplodus puntazzo)
BMC Genomics, 2014Co-Authors: Tereza Manousaki, Alexandros Tsakogiannis, Jacques Lagnel, Elena Sarropoulou, Nikos Papandroulakis, Constantinos C Mylonas, Jenny Z. Xiang, Costas S TsigenopoulosAbstract:Background: Teleosts are characterized by a remarkable breadth of sexual mechanisms including various forms of hermaphroditism. Sparidae is a fish family exhibiting Gonochorism or hermaphroditism even in closely related species. The sparid Diplodus puntazzo (sharpsnout seabream), exhibits rudimentary hermaphroditism characterized by intersexual immature gonads but single-sex mature ones. Apart from the intriguing reproductive biology, it is economically important with a continuously growing aquaculture in the Mediterranean Sea, but limited available genetic resources. Our aim was to characterize the expressed transcriptome of gonads and brains through RNA-Sequencing and explore the properties of genes that exhibit sex-biased expression profiles. Results: Through RNA-Sequencing we obtained an assembled transcriptome of 82,331 loci. The expression analysis uncovered remarkable differences between male and female gonads, while male and female brains were almost identical. Focused search for known targets of sex determination and differentiation in vertebrates built the sex-specific expression profile of sharpsnout seabream. Finally, a thorough genetic marker discovery pipeline led to the retrieval of 85,189 SNPs and 29,076 microsatellites enriching the available genetic markers for this species. Conclusions: We obtained a nearly complete source of transcriptomic sequence as well as marker information for sharpsnout seabream, laying the ground for understanding the complex process of sex differentiation of this economically valuable species. The genes involved include known candidates from other vertebrate species, suggesting a conservation of the toolkit between gonochorists and hermaphrodites.
Marc Mangel - One of the best experts on this subject based on the ideXlab platform.
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selectivity matters rules of thumb for management of plate sized sex changing fish in the live reef food fish trade
Fish and Fisheries, 2017Co-Authors: Holly K Kindsvater, Marc Mangel, John D. Reynolds, Yvonne Sadovy De MitchesonAbstract:Effective management of fisheries depends on the selectivity of different fishing methods, control of fishing effort and the life history and mating system of the target species. For sex-changing species, it is unclear how the truncation of age-structure or selection of specific size or age classes (by fishing for specific markets) affects population dynamics. We specifically address the consequences of plate-sized selectivity, whereby submature, “plate-sized” fish are preferred in the live reef food fish trade. We use an age-structured model to investigate the decline and recovery of populations fished with three different selectivity scenarios (asymptotic, dome-shaped and plate-sized) applied to two sexual systems (female-first hermaphroditism and Gonochorism). We parameterized our model with life-history data from Brown-marbled grouper (Epinephelus fuscoguttatus) and Napoleon fish (Cheilinus undulatus). “Plate-sized” selectivity had the greatest negative effect on population trajectories, assuming accumulated fishing effort across ages was equal, while the relative effect of fishing on biomass was greatest with low natural mortality. Fishing such sex-changing species before maturation decreased egg production (and the spawning potential ratio) in two ways: average individual size decreased and, assuming plasticity, females became males at a smaller size. Somatic growth rate affected biomass if selectivity was based on size at age because in slow growers, a smaller proportion of total biomass was vulnerable to fishing. We recommend fisheries avoid taking individuals near their maturation age, regardless of mating system, unless catch is tightly controlled. We also discuss the implications of fishing post-settlement individuals on population dynamics and offer practical management recommendations.
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selectivity matters rules of thumb for management of plate sized sex changing fish in the live reef food fish trade
Fish and Fisheries, 2017Co-Authors: Holly K Kindsvater, Marc Mangel, John D. Reynolds, Yvonne Sadovy De MitchesonAbstract:Effective management of fisheries depends on the selectivity of different fishing methods, control of fishing effort and the life history and mating system of the target species. For sex-changing species, it is unclear how the truncation of age-structure or selection of specific size or age classes (by fishing for specific markets) affects population dynamics. We specifically address the consequences of plate-sized selectivity, whereby submature, “plate-sized” fish are preferred in the live reef food fish trade. We use an age-structured model to investigate the decline and recovery of populations fished with three different selectivity scenarios (asymptotic, dome-shaped and plate-sized) applied to two sexual systems (female-first hermaphroditism and Gonochorism). We parameterized our model with life-history data from Brown-marbled grouper (Epinephelus fuscoguttatus) and Napoleon fish (Cheilinus undulatus). “Plate-sized” selectivity had the greatest negative effect on population trajectories, assuming accumulated fishing effort across ages was equal, while the relative effect of fishing on biomass was greatest with low natural mortality. Fishing such sex-changing species before maturation decreased egg production (and the spawning potential ratio) in two ways: average individual size decreased and, assuming plasticity, females became males at a smaller size. Somatic growth rate affected biomass if selectivity was based on size at age because in slow growers, a smaller proportion of total biomass was vulnerable to fishing. We recommend fisheries avoid taking individuals near their maturation age, regardless of mating system, unless catch is tightly controlled. We also discuss the implications of fishing post-settlement individuals on population dynamics and offer practical management recommendations.
Nikos Papandroulakis - One of the best experts on this subject based on the ideXlab platform.
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the sex specific transcriptome of the hermaphrodite sparid sharpsnout seabream diplodus puntazzo
BMC Genomics, 2014Co-Authors: Tereza Manousaki, Alexandros Tsakogiannis, Jacques Lagnel, Elena Sarropoulou, Jenny Xiang, Nikos Papandroulakis, Constantinos C Mylonas, Costas S TsigenopoulosAbstract:Teleosts are characterized by a remarkable breadth of sexual mechanisms including various forms of hermaphroditism. Sparidae is a fish family exhibiting Gonochorism or hermaphroditism even in closely related species. The sparid Diplodus puntazzo (sharpsnout seabream), exhibits rudimentary hermaphroditism characterized by intersexual immature gonads but single-sex mature ones. Apart from the intriguing reproductive biology, it is economically important with a continuously growing aquaculture in the Mediterranean Sea, but limited available genetic resources. Our aim was to characterize the expressed transcriptome of gonads and brains through RNA-Sequencing and explore the properties of genes that exhibit sex-biased expression profiles. Through RNA-Sequencing we obtained an assembled transcriptome of 82,331 loci. The expression analysis uncovered remarkable differences between male and female gonads, while male and female brains were almost identical. Focused search for known targets of sex determination and differentiation in vertebrates built the sex-specific expression profile of sharpsnout seabream. Finally, a thorough genetic marker discovery pipeline led to the retrieval of 85,189 SNPs and 29,076 microsatellites enriching the available genetic markers for this species. We obtained a nearly complete source of transcriptomic sequence as well as marker information for sharpsnout seabream, laying the ground for understanding the complex process of sex differentiation of this economically valuable species. The genes involved include known candidates from other vertebrate species, suggesting a conservation of the toolkit between gonochorists and hermaphrodites.
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The sex-specific transcriptome of the hermaphrodite sparid sharpsnout seabream (Diplodus puntazzo)
BMC Genomics, 2014Co-Authors: Tereza Manousaki, Alexandros Tsakogiannis, Jacques Lagnel, Elena Sarropoulou, Nikos Papandroulakis, Constantinos C Mylonas, Jenny Z. Xiang, Costas S TsigenopoulosAbstract:Background: Teleosts are characterized by a remarkable breadth of sexual mechanisms including various forms of hermaphroditism. Sparidae is a fish family exhibiting Gonochorism or hermaphroditism even in closely related species. The sparid Diplodus puntazzo (sharpsnout seabream), exhibits rudimentary hermaphroditism characterized by intersexual immature gonads but single-sex mature ones. Apart from the intriguing reproductive biology, it is economically important with a continuously growing aquaculture in the Mediterranean Sea, but limited available genetic resources. Our aim was to characterize the expressed transcriptome of gonads and brains through RNA-Sequencing and explore the properties of genes that exhibit sex-biased expression profiles. Results: Through RNA-Sequencing we obtained an assembled transcriptome of 82,331 loci. The expression analysis uncovered remarkable differences between male and female gonads, while male and female brains were almost identical. Focused search for known targets of sex determination and differentiation in vertebrates built the sex-specific expression profile of sharpsnout seabream. Finally, a thorough genetic marker discovery pipeline led to the retrieval of 85,189 SNPs and 29,076 microsatellites enriching the available genetic markers for this species. Conclusions: We obtained a nearly complete source of transcriptomic sequence as well as marker information for sharpsnout seabream, laying the ground for understanding the complex process of sex differentiation of this economically valuable species. The genes involved include known candidates from other vertebrate species, suggesting a conservation of the toolkit between gonochorists and hermaphrodites.