The Experts below are selected from a list of 126 Experts worldwide ranked by ideXlab platform

James Tregear - One of the best experts on this subject based on the ideXlab platform.

  • REVIEW: PART OF A SPECIAL ISSUE ON PALM BIOLOGY Environmental regulation of Sex Determination in oil palm: current knowledge and insights from other species
    2020
    Co-Authors: Myriam Collin, Thierry Beulé, David Cros, Alphonse Omoré, Leifi Nodichao, Bruno Nouy, James Tregear
    Abstract:

    † Background The African oil palm (Elaeis guineensis) is a monoecious species of the palm subfamily Arecoideae. It may be qualified as ‘temporally dioecious’ in that it produces functionally uniSexual male and female inflorescences in an alternating cycle on the same plant, resulting in an allogamous mode of reproduction. The ‘Sex ratio’ of an oil palm stand is influenced by both genetic and environmental factors. In particular, the enhancement of male inflorescence production in response to water stress has been well documented. † Scope This paper presents a review of our current understanding of the Sex Determination Process in oil palm and discusses possible insights that can be gained from other species. Although some informative phenological studies have been carried out, nothing is as yet known about the genetic basis of Sex Determination in oil palm, nor the mechanisms by which this Process is regulated. Nevertheless new genomics-based techniques, when combined with field studies and biochemical and molecular cytological-based approaches, should provide a new understanding of the complex Processes governing oil palm Sex Determination in the foreseeable future. Current hypotheses and strategies for future research are discussed.

  • Environmental regulation of Sex Determination in oil palm: current knowledge and insights from other species
    Annals of Botany, 2011
    Co-Authors: Hélène Adam, Myriam Collin, Frédérique Richaud, Thierry Beulé, David Cros, Alphonse Omoré, Leifi Nodichao, Bruno Nouy, James Tregear
    Abstract:

    Background The African oil palm (Elaeis guineensis) is a monoecious species of the palm subfamily Arecoideae. It may be qualified as 'temporally dioecious' in that it produces functionally uniSexual male and female inflorescences in an alternating cycle on the same plant, resulting in an allogamous mode of reproduction. The 'Sex ratio' of an oil palm stand is influenced by both genetic and environmental factors. In particular, the enhancement of male inflorescence production in response to water stress has been well documented. Scope This paper presents a review of our current understanding of the Sex Determination Process in oil palm and discusses possible insights that can be gained from other species. Although some informative phenological studies have been carried out, nothing is as yet known about the genetic basis of Sex Determination in oil palm, nor the mechanisms by which this Process is regulated. Nevertheless new genomics-based techniques, when combined with field studies and biochemical and molecular cytological-based approaches, should provide a new understanding of the complex Processes governing oil palm Sex Determination in the foreseeable future. Current hypotheses and strategies for future research are discussed. (Resume d'auteur)

Marek Switonski - One of the best experts on this subject based on the ideXlab platform.

  • Differentiated evolutionary conservatism and lack of polymorphism of crucial Sex Determination genes (SRY and SOX9) in four species of the family Canidae.
    Folia biologica, 2020
    Co-Authors: Joanna Nowacka-woszuk, Marek Switonski
    Abstract:

    The Sex Determination Process is under the control of several genes of which two (SRY and SOX9), encoding transcription factors, play a crucial role. It is well-known that mutations at these genes may cause the development of an interSexual phenotype. The aim of this study was to conduct a comparative analysis of the coding sequence and 5'-flanking regions of both genes in four species of the family Canidae (the dog, red fox, arctic fox and Chinese raccoon dog). Similarity of the coding sequence of the SOX9 gene among the studied species was higher (99.7-99.9%) than in the case of the SRY gene (96.7-97.3%). Only single nucleotide changes were found in the compared coding sequences, whereas in the 5'-flanking region of both genes nucleotide substitutions, as well as insertions and deletions were observed. None of the changes detected in the 5'-flanking region occurred within the potential consensus sequences for transcription factors. No polymorphism was found for either of these genes in any of the analyzed species.

  • Differentiated evolutionary conservatism and lack of polymorphism of crucial Sex Determination genes (SRY and SOX9) in four species of the family Canidae.
    Folia Biologica-krakow, 2009
    Co-Authors: Joanna Nowacka-woszuk, Marek Switonski
    Abstract:

    NOWACKA-WOSZUK J., SWITONSKIM. 2009. Differentiated evolutionary conservatism and lack of polymorphism of crucial Sex Determination genes (SRY and SOX9) in four species of the family Canidae. Folia biol. (Krakow) 57: 171-176. The Sex Determination Process is under the control of several genes of which two (SRY and SOX9), encoding transcription factors, play a crucial role. It is well-known that mutations at these genes may cause the development of an interSexual phenotype. The aim of this study was to conduct a comparative analysis of the coding sequence and 5’-flanking regions of both genes in four species of the family Canidae (the dog, red fox, arctic fox and Chinese raccoon dog). Similarity of the coding sequence of the SOX9 gene among the studied species was higher (99.7-99.9%) than in the case of the SRY gene (96.7-97.3%). Only single nucleotide changes were found in the compared coding sequences, whereas in the 5’-flanking region of both genes nucleotide substitutions, as well as insertions and deletions were observed. None of the changes detected in the 5’-flanking region occurred within the potential consensus sequences for transcription factors. No polymorphism was found for either of these genes in any of the analyzed species.

Myriam Collin - One of the best experts on this subject based on the ideXlab platform.

  • REVIEW: PART OF A SPECIAL ISSUE ON PALM BIOLOGY Environmental regulation of Sex Determination in oil palm: current knowledge and insights from other species
    2020
    Co-Authors: Myriam Collin, Thierry Beulé, David Cros, Alphonse Omoré, Leifi Nodichao, Bruno Nouy, James Tregear
    Abstract:

    † Background The African oil palm (Elaeis guineensis) is a monoecious species of the palm subfamily Arecoideae. It may be qualified as ‘temporally dioecious’ in that it produces functionally uniSexual male and female inflorescences in an alternating cycle on the same plant, resulting in an allogamous mode of reproduction. The ‘Sex ratio’ of an oil palm stand is influenced by both genetic and environmental factors. In particular, the enhancement of male inflorescence production in response to water stress has been well documented. † Scope This paper presents a review of our current understanding of the Sex Determination Process in oil palm and discusses possible insights that can be gained from other species. Although some informative phenological studies have been carried out, nothing is as yet known about the genetic basis of Sex Determination in oil palm, nor the mechanisms by which this Process is regulated. Nevertheless new genomics-based techniques, when combined with field studies and biochemical and molecular cytological-based approaches, should provide a new understanding of the complex Processes governing oil palm Sex Determination in the foreseeable future. Current hypotheses and strategies for future research are discussed.

  • Environmental regulation of Sex Determination in oil palm: current knowledge and insights from other species
    Annals of Botany, 2011
    Co-Authors: Hélène Adam, Myriam Collin, Frédérique Richaud, Thierry Beulé, David Cros, Alphonse Omoré, Leifi Nodichao, Bruno Nouy, James Tregear
    Abstract:

    Background The African oil palm (Elaeis guineensis) is a monoecious species of the palm subfamily Arecoideae. It may be qualified as 'temporally dioecious' in that it produces functionally uniSexual male and female inflorescences in an alternating cycle on the same plant, resulting in an allogamous mode of reproduction. The 'Sex ratio' of an oil palm stand is influenced by both genetic and environmental factors. In particular, the enhancement of male inflorescence production in response to water stress has been well documented. Scope This paper presents a review of our current understanding of the Sex Determination Process in oil palm and discusses possible insights that can be gained from other species. Although some informative phenological studies have been carried out, nothing is as yet known about the genetic basis of Sex Determination in oil palm, nor the mechanisms by which this Process is regulated. Nevertheless new genomics-based techniques, when combined with field studies and biochemical and molecular cytological-based approaches, should provide a new understanding of the complex Processes governing oil palm Sex Determination in the foreseeable future. Current hypotheses and strategies for future research are discussed. (Resume d'auteur)

D. Mcbride - One of the best experts on this subject based on the ideXlab platform.

  • Evidence for avian cell autonomous Sex identity (CASI) and implications for the Sex-Determination Process?
    Chromosome Research, 2012
    Co-Authors: M. Clinton, D. Zhao, S. Nandi, D. Mcbride
    Abstract:

    For the majority of animals, males and females are obviously different in terms of appearance, behaviour and physiology, and until recently, these differences were considered to be the result of hormone actions. However, there is now considerable evidence that the development of some Sexually dimorphic structures/behaviours is a function of properties inherent to male and female cells (hormone independent). The relative contribution of hormones and cellular identity to the development of the phenotype is not clear and is likely to vary from species to species. The study of gynandromorph birds and chimeric embryos has greatly assisted efforts to distinguish between the effects of hormones and inherent cellular factors on phenotype. It is now clear that in birds, male/female differences are not primarily the result of hormone action and that male and female somatic cells possess a cell autonomous Sex identity (CASI). Here, we review evidence for CASI in birds and discuss the implications for the Process of Sex Determination.

Kenji Toyota - One of the best experts on this subject based on the ideXlab platform.

  • Protein kinase C is involved with upstream signaling of methyl farnesoate for photoperiod-dependent Sex Determination in the water flea Daphnia pulex
    Biology Open, 2017
    Co-Authors: Kenji Toyota, Tomomi Sato, Norihisa Tatarazako, Taisen Iguchi
    Abstract:

    Sex Determination of Daphnia pulex is decided by environmental conditions. We established a suitable experimental system for this study using D. pulex WTN6 strain, in which the Sex of the offspring can be controlled by photoperiod. Long-day conditions induced females and short-day conditions induced males. Using this system, we previously found that methy farnesoate (MF), which is a putative innate juvenile hormone molecule in daphnids, is necessary for male Sex Determination and that protein kinase C (PKC) is a candidate factor of male Sex determiner. In this study, we demonstrated that a PKC inhibitor (bisindolylmaleimide IV: BIM) strongly suppressed male offspring induction in the short-day condition. Moreover, co-treatment of BIM with MF revealed that PKC signalling acts up-stream of the MF signalling for male Sex Determination. This is the first experimental evidence that PKC is involved in the male Sex Determination Process.

  • Photoperiodism of Male Offspring Production in the Water Flea Daphnia pulex
    Zoological Science, 2017
    Co-Authors: Kenji Toyota, Tomomi Sato, Norihisa Tatarazako, Takahiro Iguchi
    Abstract:

    Photoperiodism is a biological seasonal timing system utilized to regulate development and reproduction in organisms. The freshwater micro-crustacean Daphnia pulex displays environmental Sex Determination, the precise physiological mechanisms of which are largely unknown due to the lack of an experimental system to induce female or male offspring production by alterations of the rearing environment. We recently found that D. pulex, WTN6 strain, produces female or male offspring in response to long-day or short-day conditions, respectively. Taking advantage of this system, here we report the photoperiodic response curve for male offspring production, showing 12 hours as natural critical daylength (50% incidence of male-producing mothers), and that male offspring inducibility is highly sensitive to photoperiodic alterations. By using monochromatic light emitting diode (LED) devices, we found that the effective wavelength is red-light (627 nm), which stably induces male offspring production. This suggests that the red-light photoreceptor may be decisive in the primary step of Sex Determination Process in this strain. Our findings provide the first insights into photoperiodism and red-light as key factors in triggering male offspring production in daphnids.