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Anal Fin
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Yukiko Ogino – One of the best experts on this subject based on the ideXlab platform.
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Effects of 17β-trenbolone on Eastern and Western mosquitofish (Gambusia holbrooki and G. afFinis) Anal Fin growth and gene expression patterns.
Aquatic toxicology (Amsterdam Netherlands), 2012Co-Authors: Erica K Brockmeier, Yukiko Ogino, Taisen Iguchi, David S Barber, Nancy D DenslowAbstract:The Eastern and Western mosquitofish (Gambusia holbrooki and G. afFinis) are potential bioindicator organisms for endocrine disruptors. Male mosquitofish have an elongated Anal Fin (gonopodium) used for internal fertilization whose formation is driven by androgens. Normal female mosquitofish have a normal, rounded Anal Fin which undergoes elongation into a gonopodium structure when female mosquitofish are exposed to androgenic chemicals. Significant issues with using mosquitofish as a bioindicator include the lack of knowledge on how Anal Fin growth in females corresponds to endpoints relevant to biological integrity and the lack of information on the molecular pathways that regulate Anal Fin growth. The objectives of this study were to understand how androgen-induced Anal Fin elongation relates to changes in endpoints related to the female reproductive system and to understand how Anal Fin elongation occurs in androgen-exposed female mosquitofish. To achieve these objectives, adult female G. holbrooki were exposed to a vehicle control or one of three doses of the androgen 17β-trenbolone (TB) at nominal concentrations of 0.1, 1 or 10 μg TB/L. Anal Fin measurements were taken and livers were used for quantitative polymerase chain reaction Analysis of vitellogenin (vtg) mRNA expression at multiple time points. 10 μg TB/L induced Anal Fin elongation after 7 days of treatment (one-way ANOVA, p
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Effects of 17β-trenbolone on Eastern and Western mosquitofish (Gambusia holbrooki and G. afFinis) Anal Fin growth and gene expression patterns
Aquatic Toxicology, 2012Co-Authors: Erica K Brockmeier, Yukiko Ogino, Taisen Iguchi, David S Barber, Nancy D DenslowAbstract:Abstract The Eastern and Western mosquitofish (Gambusia holbrooki and G. afFinis) are potential bioindicator organisms for endocrine disruptors. Male mosquitofish have an elongated Anal Fin (gonopodium) used for internal fertilization whose formation is driven by androgens. Normal female mosquitofish have a normal, rounded Anal Fin which undergoes elongation into a gonopodium structure when female mosquitofish are exposed to androgenic chemicals. Significant issues with using mosquitofish as a bioindicator include the lack of knowledge on how Anal Fin growth in females corresponds to endpoints relevant to biological integrity and the lack of information on the molecular pathways that regulate Anal Fin growth. The objectives of this study were to understand how androgen-induced Anal Fin elongation relates to changes in endpoints related to the female reproductive system and to understand how Anal Fin elongation occurs in androgen-exposed female mosquitofish. To achieve these objectives, adult female G. holbrooki were exposed to a vehicle control or one of three doses of the androgen 17β-trenbolone (TB) at nominal concentrations of 0.1, 1 or 10 μg TB/L. Anal Fin measurements were taken and livers were used for quantitative polymerase chain reaction Analysis of vitellogenin (vtg) mRNA expression at multiple time points. 10 μg TB/L induced Anal Fin elongation after 7 days of treatment (one-way ANOVA, p 0.05). In a separate experiment, female G. holbrooki and G. afFinis were exposed to the vehicle control or 1 μg TB/L. Anal Fins were used for qualitative gene expression Analysis of the genes sonic hedgehog (shh), muscle segment homeobox C (msxC), and fibroblast growth factor receptor 1 (fgfr1) by in situ hybridization. Shh was expressed in the distal tip of the gonopodium while msxC and fgfr1 were more widely expressed along the same Anal Fin rays during androgen exposure. These data provide insight into the molecular pathways involved in Anal Fin elongation and pave the way for future work toward developing the mosquitofish into a bioindicator organism for endocrine disruptors.
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Androgen dependent development of a modified Anal Fin, gonopodium, as a model to understand the mechanism of secondary sexual character expression in vertebrates.
FEBS Letters, 2004Co-Authors: Yukiko Ogino, Hironori Katoh, YamadaAbstract:Male external genitalia show structural variations among species. Androgenic hormones are essential for the morphological specification of male type copulatory organs, while little is known about the developmental mechanisms of such secondary sexual characters. Western mosquitofish Gambusia afFinis may offer a clue to the sexual differentiation researches, because they show a prominent masculine sexual character for appendage development, Anal Fin to gonopodium (GP) transition, and its formation could be induced in early juvenile fry by exogenously supplied androgens. We show that GP development is promoted by androgen dependent augmentation of sonic hedgehog (Shh) expression. Two AR cDNAs were cloned and identified as ARα and ARβ from western mosquitofish. Both ARs were predominantly expressed in the distal region of outgrowing Anal Fin rays. Exposure of fry to androgen caused Anal Fin outgrowth concomitant with the Shh induction in the distal Anal Fin ray epithelium. When AR signaling was inhibited by its antagonist flutamide in fry, the initial induction of the Shh was suppressed accompanying retarded Anal Fin outgrowth. Similar suppression of Anal Fin outgrowth was induced by treatment with cyclopamine, an inhibitor of Shh signaling. These observations indicate that androgen dependent Shh expression is required for Anal Fin outgrowth leading to the formation of a genital appendage, the GP in teleost fishes. Androgen-induced GP formation may provide insights into the expression mechanism regulating the specification of sexual features in vertebrates.
Nancy D Denslow – One of the best experts on this subject based on the ideXlab platform.
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Effects of 17β-trenbolone on Eastern and Western mosquitofish (Gambusia holbrooki and G. afFinis) Anal Fin growth and gene expression patterns.
Aquatic toxicology (Amsterdam Netherlands), 2012Co-Authors: Erica K Brockmeier, Yukiko Ogino, Taisen Iguchi, David S Barber, Nancy D DenslowAbstract:The Eastern and Western mosquitofish (Gambusia holbrooki and G. afFinis) are potential bioindicator organisms for endocrine disruptors. Male mosquitofish have an elongated Anal Fin (gonopodium) used for internal fertilization whose formation is driven by androgens. Normal female mosquitofish have a normal, rounded Anal Fin which undergoes elongation into a gonopodium structure when female mosquitofish are exposed to androgenic chemicals. Significant issues with using mosquitofish as a bioindicator include the lack of knowledge on how Anal Fin growth in females corresponds to endpoints relevant to biological integrity and the lack of information on the molecular pathways that regulate Anal Fin growth. The objectives of this study were to understand how androgen-induced Anal Fin elongation relates to changes in endpoints related to the female reproductive system and to understand how Anal Fin elongation occurs in androgen-exposed female mosquitofish. To achieve these objectives, adult female G. holbrooki were exposed to a vehicle control or one of three doses of the androgen 17β-trenbolone (TB) at nominal concentrations of 0.1, 1 or 10 μg TB/L. Anal Fin measurements were taken and livers were used for quantitative polymerase chain reaction Analysis of vitellogenin (vtg) mRNA expression at multiple time points. 10 μg TB/L induced Anal Fin elongation after 7 days of treatment (one-way ANOVA, p
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Effects of 17β-trenbolone on Eastern and Western mosquitofish (Gambusia holbrooki and G. afFinis) Anal Fin growth and gene expression patterns
Aquatic Toxicology, 2012Co-Authors: Erica K Brockmeier, Yukiko Ogino, Taisen Iguchi, David S Barber, Nancy D DenslowAbstract:Abstract The Eastern and Western mosquitofish (Gambusia holbrooki and G. afFinis) are potential bioindicator organisms for endocrine disruptors. Male mosquitofish have an elongated Anal Fin (gonopodium) used for internal fertilization whose formation is driven by androgens. Normal female mosquitofish have a normal, rounded Anal Fin which undergoes elongation into a gonopodium structure when female mosquitofish are exposed to androgenic chemicals. Significant issues with using mosquitofish as a bioindicator include the lack of knowledge on how Anal Fin growth in females corresponds to endpoints relevant to biological integrity and the lack of information on the molecular pathways that regulate Anal Fin growth. The objectives of this study were to understand how androgen-induced Anal Fin elongation relates to changes in endpoints related to the female reproductive system and to understand how Anal Fin elongation occurs in androgen-exposed female mosquitofish. To achieve these objectives, adult female G. holbrooki were exposed to a vehicle control or one of three doses of the androgen 17β-trenbolone (TB) at nominal concentrations of 0.1, 1 or 10 μg TB/L. Anal Fin measurements were taken and livers were used for quantitative polymerase chain reaction Analysis of vitellogenin (vtg) mRNA expression at multiple time points. 10 μg TB/L induced Anal Fin elongation after 7 days of treatment (one-way ANOVA, p 0.05). In a separate experiment, female G. holbrooki and G. afFinis were exposed to the vehicle control or 1 μg TB/L. Anal Fins were used for qualitative gene expression Analysis of the genes sonic hedgehog (shh), muscle segment homeobox C (msxC), and fibroblast growth factor receptor 1 (fgfr1) by in situ hybridization. Shh was expressed in the distal tip of the gonopodium while msxC and fgfr1 were more widely expressed along the same Anal Fin rays during androgen exposure. These data provide insight into the molecular pathways involved in Anal Fin elongation and pave the way for future work toward developing the mosquitofish into a bioindicator organism for endocrine disruptors.
Axel Meyer – One of the best experts on this subject based on the ideXlab platform.
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transcriptomics of two evolutionary novelties how to make a sperm transfer organ out of an Anal Fin and a sexually selected sword out of a caudal Fin
Ecology and Evolution, 2015Co-Authors: Ji Hyoun Kang, Tereza Manousaki, Paolo Franchini, Susanne Kneitz, Manfred Schartl, Axel MeyerAbstract:Swords are exaggerated male ornaments of swordtail fishes that have been of great interest to evolutionary biologists ever since Darwin described them in the Descent of Man (1871). They are a novel sexually selected trait derived from modified ventral caudal Fin rays and are only found in the genus Xiphophorus. Another phylogenetically more widespread and older male trait is the gonopodium, an intromittent organ found in all poeciliid fishes, that is derived from a modified Anal Fin. Despite many evolutionary and behavioral studies on both traits, little is known so far about the molecular mechanisms underlying their development. By investigating transcriptomic changes (utilizing a RNA-Seq approach) in response to testosterone treatment in the swordtail fish, Xiphophorus hellerii, we aimed to better understand the architecture of the gene regulatory networks underpinning the development of these two evolutionary novelties. Large numbers of genes with tissue-specific expression patterns were identified. Among the “sword genes” those involved in embryonic organ development, sexual character development and coloration were highly expressed, while in the gonopodium rather more morphogenesis-related genes were found. Interestingly, many genes and genetic pathways are shared between both developing novel traits derived from median Fins: the sword and the gonopodium. Our Analyses show that a larger set of gene networks was co-opted during the development and evolution of the “older” gonopodium than in the “younger,” and morphologically less complex trait, the sword. We provide a catalog of candidate genes for future efforts to dissect the development of those sexually selected exaggerated male traits in swordtails.
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Transcriptomics of two evolutionary novelties: how to make a sperm‐transfer organ out of an Anal Fin and a sexually selected “sword” out of a caudal Fin
Ecology and evolution, 2015Co-Authors: Ji Hyoun Kang, Tereza Manousaki, Paolo Franchini, Susanne Kneitz, Manfred Schartl, Axel MeyerAbstract:Swords are exaggerated male ornaments of swordtail fishes that have been of great interest to evolutionary biologists ever since Darwin described them in the Descent of Man (1871). They are a novel sexually selected trait derived from modified ventral caudal Fin rays and are only found in the genus Xiphophorus. Another phylogenetically more widespread and older male trait is the gonopodium, an intromittent organ found in all poeciliid fishes, that is derived from a modified Anal Fin. Despite many evolutionary and behavioral studies on both traits, little is known so far about the molecular mechanisms underlying their development. By investigating transcriptomic changes (utilizing a RNA-Seq approach) in response to testosterone treatment in the swordtail fish, Xiphophorus hellerii, we aimed to better understand the architecture of the gene regulatory networks underpinning the development of these two evolutionary novelties. Large numbers of genes with tissue-specific expression patterns were identified. Among the “sword genes” those involved in embryonic organ development, sexual character development and coloration were highly expressed, while in the gonopodium rather more morphogenesis-related genes were found. Interestingly, many genes and genetic pathways are shared between both developing novel traits derived from median Fins: the sword and the gonopodium. Our Analyses show that a larger set of gene networks was co-opted during the development and evolution of the “older” gonopodium than in the “younger,” and morphologically less complex trait, the sword. We provide a catalog of candidate genes for future efforts to dissect the development of those sexually selected exaggerated male traits in swordtails.
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Retinoic Acid Is Involved in the Metamorphosis of the Anal Fin into an Intromittent Organ, the Gonopodium, in the Green Swordtail (Xiphophorus hellerii).
PloS one, 2013Co-Authors: Nils Offen, Ji Hyoun Kang, Axel Meyer, Gerrit BegemannAbstract:In poeciliid fish the male Anal Fin has been transformed into a gonopodium, an intromittent organ required for internal fertilization. Elevated testosterone levels induce metamorphosis of a subset of Anal Fin rays to grow and form the specialized terminal structures of the gonopodium. The molecular mechanisms underlying these processes are largely unknown. Here, we investigated whether retinoic acid (RA) signaling is involved in gonopodium development in the swordtail Xiphophorus hellerii. We showed that aldh1a2, a RA synthesizing enzyme, and the RA receptors, rar-ga and rar-gb, are expressed in Anal Fins during metamorphosis. aldh1a2 expression is regulated by testosterone in a concentration-dependent manner and is up-regulated in both hormone-induced and naturally developing gonopodia. Androgen receptor (ar), a putative regulator of gonopodial development, is co-expressed with aldh1a2 and the RA receptors in gonopodial rays. Importantly, experimental increase of RA signaling promoted growth of the gonopodium and increased the number of new segments. Based on gene expression Analyses and pharmacological manipulation of gonopodium development, we show that the RA signaling pathway is activated in response to androgen signaling and promotes Fin ray growth and development during the metamorphosis of the Anal Fin into the gonopodium.
Erica K Brockmeier – One of the best experts on this subject based on the ideXlab platform.
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Effects of 17β-trenbolone on Eastern and Western mosquitofish (Gambusia holbrooki and G. afFinis) Anal Fin growth and gene expression patterns.
Aquatic toxicology (Amsterdam Netherlands), 2012Co-Authors: Erica K Brockmeier, Yukiko Ogino, Taisen Iguchi, David S Barber, Nancy D DenslowAbstract:The Eastern and Western mosquitofish (Gambusia holbrooki and G. afFinis) are potential bioindicator organisms for endocrine disruptors. Male mosquitofish have an elongated Anal Fin (gonopodium) used for internal fertilization whose formation is driven by androgens. Normal female mosquitofish have a normal, rounded Anal Fin which undergoes elongation into a gonopodium structure when female mosquitofish are exposed to androgenic chemicals. Significant issues with using mosquitofish as a bioindicator include the lack of knowledge on how Anal Fin growth in females corresponds to endpoints relevant to biological integrity and the lack of information on the molecular pathways that regulate Anal Fin growth. The objectives of this study were to understand how androgen-induced Anal Fin elongation relates to changes in endpoints related to the female reproductive system and to understand how Anal Fin elongation occurs in androgen-exposed female mosquitofish. To achieve these objectives, adult female G. holbrooki were exposed to a vehicle control or one of three doses of the androgen 17β-trenbolone (TB) at nominal concentrations of 0.1, 1 or 10 μg TB/L. Anal Fin measurements were taken and livers were used for quantitative polymerase chain reaction Analysis of vitellogenin (vtg) mRNA expression at multiple time points. 10 μg TB/L induced Anal Fin elongation after 7 days of treatment (one-way ANOVA, p
-
Effects of 17β-trenbolone on Eastern and Western mosquitofish (Gambusia holbrooki and G. afFinis) Anal Fin growth and gene expression patterns
Aquatic Toxicology, 2012Co-Authors: Erica K Brockmeier, Yukiko Ogino, Taisen Iguchi, David S Barber, Nancy D DenslowAbstract:Abstract The Eastern and Western mosquitofish (Gambusia holbrooki and G. afFinis) are potential bioindicator organisms for endocrine disruptors. Male mosquitofish have an elongated Anal Fin (gonopodium) used for internal fertilization whose formation is driven by androgens. Normal female mosquitofish have a normal, rounded Anal Fin which undergoes elongation into a gonopodium structure when female mosquitofish are exposed to androgenic chemicals. Significant issues with using mosquitofish as a bioindicator include the lack of knowledge on how Anal Fin growth in females corresponds to endpoints relevant to biological integrity and the lack of information on the molecular pathways that regulate Anal Fin growth. The objectives of this study were to understand how androgen-induced Anal Fin elongation relates to changes in endpoints related to the female reproductive system and to understand how Anal Fin elongation occurs in androgen-exposed female mosquitofish. To achieve these objectives, adult female G. holbrooki were exposed to a vehicle control or one of three doses of the androgen 17β-trenbolone (TB) at nominal concentrations of 0.1, 1 or 10 μg TB/L. Anal Fin measurements were taken and livers were used for quantitative polymerase chain reaction Analysis of vitellogenin (vtg) mRNA expression at multiple time points. 10 μg TB/L induced Anal Fin elongation after 7 days of treatment (one-way ANOVA, p 0.05). In a separate experiment, female G. holbrooki and G. afFinis were exposed to the vehicle control or 1 μg TB/L. Anal Fins were used for qualitative gene expression Analysis of the genes sonic hedgehog (shh), muscle segment homeobox C (msxC), and fibroblast growth factor receptor 1 (fgfr1) by in situ hybridization. Shh was expressed in the distal tip of the gonopodium while msxC and fgfr1 were more widely expressed along the same Anal Fin rays during androgen exposure. These data provide insight into the molecular pathways involved in Anal Fin elongation and pave the way for future work toward developing the mosquitofish into a bioindicator organism for endocrine disruptors.
Ji Hyoun Kang – One of the best experts on this subject based on the ideXlab platform.
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transcriptomics of two evolutionary novelties how to make a sperm transfer organ out of an Anal Fin and a sexually selected sword out of a caudal Fin
Ecology and Evolution, 2015Co-Authors: Ji Hyoun Kang, Tereza Manousaki, Paolo Franchini, Susanne Kneitz, Manfred Schartl, Axel MeyerAbstract:Swords are exaggerated male ornaments of swordtail fishes that have been of great interest to evolutionary biologists ever since Darwin described them in the Descent of Man (1871). They are a novel sexually selected trait derived from modified ventral caudal Fin rays and are only found in the genus Xiphophorus. Another phylogenetically more widespread and older male trait is the gonopodium, an intromittent organ found in all poeciliid fishes, that is derived from a modified Anal Fin. Despite many evolutionary and behavioral studies on both traits, little is known so far about the molecular mechanisms underlying their development. By investigating transcriptomic changes (utilizing a RNA-Seq approach) in response to testosterone treatment in the swordtail fish, Xiphophorus hellerii, we aimed to better understand the architecture of the gene regulatory networks underpinning the development of these two evolutionary novelties. Large numbers of genes with tissue-specific expression patterns were identified. Among the “sword genes” those involved in embryonic organ development, sexual character development and coloration were highly expressed, while in the gonopodium rather more morphogenesis-related genes were found. Interestingly, many genes and genetic pathways are shared between both developing novel traits derived from median Fins: the sword and the gonopodium. Our Analyses show that a larger set of gene networks was co-opted during the development and evolution of the “older” gonopodium than in the “younger,” and morphologically less complex trait, the sword. We provide a catalog of candidate genes for future efforts to dissect the development of those sexually selected exaggerated male traits in swordtails.
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Transcriptomics of two evolutionary novelties: how to make a sperm‐transfer organ out of an Anal Fin and a sexually selected “sword” out of a caudal Fin
Ecology and evolution, 2015Co-Authors: Ji Hyoun Kang, Tereza Manousaki, Paolo Franchini, Susanne Kneitz, Manfred Schartl, Axel MeyerAbstract:Swords are exaggerated male ornaments of swordtail fishes that have been of great interest to evolutionary biologists ever since Darwin described them in the Descent of Man (1871). They are a novel sexually selected trait derived from modified ventral caudal Fin rays and are only found in the genus Xiphophorus. Another phylogenetically more widespread and older male trait is the gonopodium, an intromittent organ found in all poeciliid fishes, that is derived from a modified Anal Fin. Despite many evolutionary and behavioral studies on both traits, little is known so far about the molecular mechanisms underlying their development. By investigating transcriptomic changes (utilizing a RNA-Seq approach) in response to testosterone treatment in the swordtail fish, Xiphophorus hellerii, we aimed to better understand the architecture of the gene regulatory networks underpinning the development of these two evolutionary novelties. Large numbers of genes with tissue-specific expression patterns were identified. Among the “sword genes” those involved in embryonic organ development, sexual character development and coloration were highly expressed, while in the gonopodium rather more morphogenesis-related genes were found. Interestingly, many genes and genetic pathways are shared between both developing novel traits derived from median Fins: the sword and the gonopodium. Our Analyses show that a larger set of gene networks was co-opted during the development and evolution of the “older” gonopodium than in the “younger,” and morphologically less complex trait, the sword. We provide a catalog of candidate genes for future efforts to dissect the development of those sexually selected exaggerated male traits in swordtails.
-
Retinoic Acid Is Involved in the Metamorphosis of the Anal Fin into an Intromittent Organ, the Gonopodium, in the Green Swordtail (Xiphophorus hellerii).
PloS one, 2013Co-Authors: Nils Offen, Ji Hyoun Kang, Axel Meyer, Gerrit BegemannAbstract:In poeciliid fish the male Anal Fin has been transformed into a gonopodium, an intromittent organ required for internal fertilization. Elevated testosterone levels induce metamorphosis of a subset of Anal Fin rays to grow and form the specialized terminal structures of the gonopodium. The molecular mechanisms underlying these processes are largely unknown. Here, we investigated whether retinoic acid (RA) signaling is involved in gonopodium development in the swordtail Xiphophorus hellerii. We showed that aldh1a2, a RA synthesizing enzyme, and the RA receptors, rar-ga and rar-gb, are expressed in Anal Fins during metamorphosis. aldh1a2 expression is regulated by testosterone in a concentration-dependent manner and is up-regulated in both hormone-induced and naturally developing gonopodia. Androgen receptor (ar), a putative regulator of gonopodial development, is co-expressed with aldh1a2 and the RA receptors in gonopodial rays. Importantly, experimental increase of RA signaling promoted growth of the gonopodium and increased the number of new segments. Based on gene expression Analyses and pharmacological manipulation of gonopodium development, we show that the RA signaling pathway is activated in response to androgen signaling and promotes Fin ray growth and development during the metamorphosis of the Anal Fin into the gonopodium.