The Experts below are selected from a list of 27 Experts worldwide ranked by ideXlab platform

Xiaoran Chen - One of the best experts on this subject based on the ideXlab platform.

  • low concentrations of dihydrotestosterone induce female to male sex reversal in the Frog pelophylax nigromaculatus
    Environmental Toxicology and Chemistry, 2015
    Co-Authors: Wei Xu, Yuanyuan Li, Xiaoran Chen
    Abstract:

    Previous studies have demonstrated that some amphibian species can be sex-reversed by high concentrations of androgens. Little attention has focused on the effects of androgenic endocrine-disrupting chemicals (EDCs) on amphibians. The present study aimed to investigate the effects of lower concentrations of the androgenic EDC 5α-dihydrotestosterone (DHT) on gonadal differentiation and development in Pelophylax nigromaculatus, a True Frog distributed widely in East Asia. Tadpoles at Gosner stage 24/25 were exposed to nominal concentrations of 40 ng/L, 400 ng/L, and 4000 ng/L DHT to complete metamorphosis. In all DHT treatment groups, males and ambiguous sexes were identified based on gonadal morphology, whereas no females were found; thus, all treatment groups exhibited male-skewed ratios compared with the control group. Gonadal histological examination revealed that ambiguous sexes displayed overall testicular structure with certain ovarian characteristics, demonstrating that DHT-induced sex-ambiguous gonads were incomplete ovary-to-testis reversals (IOTTRs). The expression levels of some ovary-biased genes in the IOTTRs were significantly higher than in the control testes but lower than in the control ovaries. These results show that low concentrations of DHT induced complete or incomplete female-to-male sex reversal in P. nigromaculatus, and incomplete sex reversal retained certain ovarian characteristics not only at gonadal morphological and histological levels but also at the molecular level. They present study highlights potential risks of DHT and other androgenic EDCs for P. nigromaculatus. Environ Toxicol Chem 2015;34:2370–2377. © 2015 SETAC

  • Low concentrations of dihydrotestosterone induce female‐to‐male sex reversal in the Frog Pelophylax nigromaculatus
    Environmental toxicology and chemistry, 2015
    Co-Authors: Qin-qin Lou, Xiaoran Chen, Zhan-fen Qin, Wu-ji Wie
    Abstract:

    Previous studies have demonstrated that some amphibian species can be sex-reversed by high concentrations of androgens. Little attention has focused on the effects of androgenic endocrine-disrupting chemicals (EDCs) on amphibians. The present study aimed to investigate the effects of lower concentrations of the androgenic EDC 5α-dihydrotestosterone (DHT) on gonadal differentiation and development in Pelophylax nigromaculatus, a True Frog distributed widely in East Asia. Tadpoles at Gosner stage 24/25 were exposed to nominal concentrations of 40 ng/L, 400 ng/L, and 4000 ng/L DHT to complete metamorphosis. In all DHT treatment groups, males and ambiguous sexes were identified based on gonadal morphology, whereas no females were found; thus, all treatment groups exhibited male-skewed ratios compared with the control group. Gonadal histological examination revealed that ambiguous sexes displayed overall testicular structure with certain ovarian characteristics, demonstrating that DHT-induced sex-ambiguous gonads were incomplete ovary-to-testis reversals (IOTTRs). The expression levels of some ovary-biased genes in the IOTTRs were significantly higher than in the control testes but lower than in the control ovaries. These results show that low concentrations of DHT induced complete or incomplete female-to-male sex reversal in P. nigromaculatus, and incomplete sex reversal retained certain ovarian characteristics not only at gonadal morphological and histological levels but also at the molecular level. They present study highlights potential risks of DHT and other androgenic EDCs for P. nigromaculatus. Environ Toxicol Chem 2015;34:2370–2377. © 2015 SETAC

Martin Jones - One of the best experts on this subject based on the ideXlab platform.

  • The North American bullFrog draft genome provides insight into hormonal regulation of long noncoding RNA
    Nature Communications, 2017
    Co-Authors: S. Austin Hammond, René L. Warren, Benjamin P. Vandervalk, Erdi Kucuk, Hamza Khan, Ewan A. Gibb, Pawan Pandoh, Heather Kirk, Yongjun Zhao, Martin Jones
    Abstract:

    The globally-distributed Ranidae (True Frogs) are the largest Frog family. Here, Hammond et al. present a draft genome of the North American bullFrog, Rana ( Lithobates ) catesbeiana , as a foundation for future understanding of True Frog genetics as amphibian species face difficult environmental challenges. Frogs play important ecological roles, and several species are important model organisms for scientific research. The globally distributed Ranidae (True Frogs) are the largest Frog family, and have substantial evolutionary distance from the model laboratory Xenopus Frog species. Unfortunately, there are currently no genomic resources for the former, important group of amphibians. More widely applicable amphibian genomic data is urgently needed as more than two-thirds of known species are currently threatened or are undergoing population declines. We report a 5.8 Gbp (NG50 = 69 kbp) genome assembly of a representative North American bullFrog ( Rana [Lithobates] catesbeiana ). The genome contains over 22,000 predicted protein-coding genes and 6,223 candidate long noncoding RNAs (lncRNAs). RNA-Seq experiments show thyroid hormone causes widespread transcriptional change among protein-coding and putative lncRNA genes. This initial bullFrog draft genome will serve as a key resource with broad utility including amphibian research, developmental biology, and environmental research.

  • The North American bullFrog draft genome provides insight into hormonal regulation of long noncoding RNA
    Nature Publishing Group, 2017
    Co-Authors: Austin S. Hammond, René L. Warren, Benjamin P. Vandervalk, Erdi Kucuk, Hamza Khan, Ewan A. Gibb, Pawan Pandoh, Heather Kirk, Yongjun Zhao, Martin Jones
    Abstract:

    The globally-distributed Ranidae (True Frogs) are the largest Frog family. Here, Hammond et al. present a draft genome of the North American bullFrog, Rana (Lithobates) catesbeiana, as a foundation for future understanding of True Frog genetics as amphibian species face difficult environmental challenges

Wu-ji Wie - One of the best experts on this subject based on the ideXlab platform.

  • Low concentrations of dihydrotestosterone induce female‐to‐male sex reversal in the Frog Pelophylax nigromaculatus
    Environmental toxicology and chemistry, 2015
    Co-Authors: Qin-qin Lou, Xiaoran Chen, Zhan-fen Qin, Wu-ji Wie
    Abstract:

    Previous studies have demonstrated that some amphibian species can be sex-reversed by high concentrations of androgens. Little attention has focused on the effects of androgenic endocrine-disrupting chemicals (EDCs) on amphibians. The present study aimed to investigate the effects of lower concentrations of the androgenic EDC 5α-dihydrotestosterone (DHT) on gonadal differentiation and development in Pelophylax nigromaculatus, a True Frog distributed widely in East Asia. Tadpoles at Gosner stage 24/25 were exposed to nominal concentrations of 40 ng/L, 400 ng/L, and 4000 ng/L DHT to complete metamorphosis. In all DHT treatment groups, males and ambiguous sexes were identified based on gonadal morphology, whereas no females were found; thus, all treatment groups exhibited male-skewed ratios compared with the control group. Gonadal histological examination revealed that ambiguous sexes displayed overall testicular structure with certain ovarian characteristics, demonstrating that DHT-induced sex-ambiguous gonads were incomplete ovary-to-testis reversals (IOTTRs). The expression levels of some ovary-biased genes in the IOTTRs were significantly higher than in the control testes but lower than in the control ovaries. These results show that low concentrations of DHT induced complete or incomplete female-to-male sex reversal in P. nigromaculatus, and incomplete sex reversal retained certain ovarian characteristics not only at gonadal morphological and histological levels but also at the molecular level. They present study highlights potential risks of DHT and other androgenic EDCs for P. nigromaculatus. Environ Toxicol Chem 2015;34:2370–2377. © 2015 SETAC

S. Austin Hammond - One of the best experts on this subject based on the ideXlab platform.

  • The North American bullFrog draft genome provides insight into hormonal regulation of long noncoding RNA
    Nature Communications, 2017
    Co-Authors: S. Austin Hammond, René L. Warren, Benjamin P. Vandervalk, Erdi Kucuk, Hamza Khan, Ewan A. Gibb, Pawan Pandoh, Heather Kirk, Yongjun Zhao, Martin Jones
    Abstract:

    The globally-distributed Ranidae (True Frogs) are the largest Frog family. Here, Hammond et al. present a draft genome of the North American bullFrog, Rana ( Lithobates ) catesbeiana , as a foundation for future understanding of True Frog genetics as amphibian species face difficult environmental challenges. Frogs play important ecological roles, and several species are important model organisms for scientific research. The globally distributed Ranidae (True Frogs) are the largest Frog family, and have substantial evolutionary distance from the model laboratory Xenopus Frog species. Unfortunately, there are currently no genomic resources for the former, important group of amphibians. More widely applicable amphibian genomic data is urgently needed as more than two-thirds of known species are currently threatened or are undergoing population declines. We report a 5.8 Gbp (NG50 = 69 kbp) genome assembly of a representative North American bullFrog ( Rana [Lithobates] catesbeiana ). The genome contains over 22,000 predicted protein-coding genes and 6,223 candidate long noncoding RNAs (lncRNAs). RNA-Seq experiments show thyroid hormone causes widespread transcriptional change among protein-coding and putative lncRNA genes. This initial bullFrog draft genome will serve as a key resource with broad utility including amphibian research, developmental biology, and environmental research.

Pawan Pandoh - One of the best experts on this subject based on the ideXlab platform.

  • The North American bullFrog draft genome provides insight into hormonal regulation of long noncoding RNA
    Nature Communications, 2017
    Co-Authors: S. Austin Hammond, René L. Warren, Benjamin P. Vandervalk, Erdi Kucuk, Hamza Khan, Ewan A. Gibb, Pawan Pandoh, Heather Kirk, Yongjun Zhao, Martin Jones
    Abstract:

    The globally-distributed Ranidae (True Frogs) are the largest Frog family. Here, Hammond et al. present a draft genome of the North American bullFrog, Rana ( Lithobates ) catesbeiana , as a foundation for future understanding of True Frog genetics as amphibian species face difficult environmental challenges. Frogs play important ecological roles, and several species are important model organisms for scientific research. The globally distributed Ranidae (True Frogs) are the largest Frog family, and have substantial evolutionary distance from the model laboratory Xenopus Frog species. Unfortunately, there are currently no genomic resources for the former, important group of amphibians. More widely applicable amphibian genomic data is urgently needed as more than two-thirds of known species are currently threatened or are undergoing population declines. We report a 5.8 Gbp (NG50 = 69 kbp) genome assembly of a representative North American bullFrog ( Rana [Lithobates] catesbeiana ). The genome contains over 22,000 predicted protein-coding genes and 6,223 candidate long noncoding RNAs (lncRNAs). RNA-Seq experiments show thyroid hormone causes widespread transcriptional change among protein-coding and putative lncRNA genes. This initial bullFrog draft genome will serve as a key resource with broad utility including amphibian research, developmental biology, and environmental research.

  • The North American bullFrog draft genome provides insight into hormonal regulation of long noncoding RNA
    Nature Publishing Group, 2017
    Co-Authors: Austin S. Hammond, René L. Warren, Benjamin P. Vandervalk, Erdi Kucuk, Hamza Khan, Ewan A. Gibb, Pawan Pandoh, Heather Kirk, Yongjun Zhao, Martin Jones
    Abstract:

    The globally-distributed Ranidae (True Frogs) are the largest Frog family. Here, Hammond et al. present a draft genome of the North American bullFrog, Rana (Lithobates) catesbeiana, as a foundation for future understanding of True Frog genetics as amphibian species face difficult environmental challenges