One of the main causes of pregnancy failure and fetus abortion is oocyte aneuploidy,which is increased with maternal aging.Numerous possible causes of oocyte aneuploidy in aged women have been proposed,including cross...One of the main causes of pregnancy failure and fetus abortion is oocyte aneuploidy,which is increased with maternal aging.Numerous possible causes of oocyte aneuploidy in aged women have been proposed,including cross-over formation defect,cohesin loss,spindle deformation,spindle assembly checkpoint malfunction,microtubule-kinetochore attachment failure,kinetochore mis-orientation,mitochondria dysfunction-induced increases in reactive oxygen species,protein over-acetylation,and DNA damage.However,it still needs to be answered if these aneuploidization factors have inherent relations,and how to prevent chromosome aneuploidy in aged oocytes.Epidemiologically,oocyte aneuploidy has been found to be weakly associated with higher homocysteine concentrations,obesity,ionizing radiation and even seasonality.In this review,we summarize the research progress and present an integrated view of oocyte aneuploidization.展开更多
The mitochondrion is the major energy provider to power sperm motility. In mammals, aside from the nuclear genome, mitochondrial DNA （mtDNA） also contributes to oxidative phosphorylation to impact production of ATP ...The mitochondrion is the major energy provider to power sperm motility. In mammals, aside from the nuclear genome, mitochondrial DNA （mtDNA） also contributes to oxidative phosphorylation to impact production of ATP by coding 13 polypeptides. However, the role of sperm mitochondria in fertilization and its final fate after fertilization are still controversial. The viewpoints that sperm bearing more mtDNA will have a better fertilizing capability and that sperm mtDNA is actively eliminated during early embryogenesis are widely accepted. However, this may be not true for several mammalian species, including mice and humans. Here, we review the sperm mitochondria and their mtDNA in sperm functions, and the mechanisms of maternal mitochondrial inheritance in mammals.展开更多
CtBP-interacting protein(CtIP)is known for its multifaceted roles in DNA repair and genomic stability,directing the homologous recombination-mediated DNA double-stranded break repair pathway via DNA end resection,an e...CtBP-interacting protein(CtIP)is known for its multifaceted roles in DNA repair and genomic stability,directing the homologous recombination-mediated DNA double-stranded break repair pathway via DNA end resection,an essential error-free repair process vital for genome stability.Mammalian oocytes are highly prone to DNA damage accumulation due to prolonged G2/prophase arrest.Here,we explore the functions of CtIP in meiotic cell cycle regulation via a mouse oocyte model.Depletion of CtIP by siRNA injection results in delayed germinal vesicle breakdown and failed polar body extrusion.Mechanistically,CtIP deficiency increases DNA damage and decreases the expression and nuclear entry of CCNB1,resulting in marked impairment of meiotic resumption,which can be rescued by exogenous CCNB1 overexpression.Furthermore,depletion of CtIP disrupts microtubule-organizing centers coalescence at spindle poles as indicated by failed accumulation ofγ-tubulin,p-Aurora kinase A,Kif2A,and TPX2,leading to abnormal spindle assembly and prometaphase arrest.These results provide valuable insights into the important roles of CtIP in the G2/M checkpoint and spindle assembly in mouse oocyte meiotic cell cycle regulation.展开更多
In comparison to conventional knockout technology and in vitro research methods, conditional gene knockout has remarkable advantages. In the past decade, especially during the past five years, conditional knockout app...In comparison to conventional knockout technology and in vitro research methods, conditional gene knockout has remarkable advantages. In the past decade, especially during the past five years, conditional knockout approaches have been used to study the regulation of folliculogenesis, follicle growth, oocyte maturation and other major reproductive events. In this review, we summarize the recent findings about folliculogenesis/oogenesis regulation, including the functions of four signaling cascades or glycoprotein domains that have been extensively studied by conditional gene deletion. Several other still fragmented areas of related work are introduced which are awaiting clarification. We have also discussed the future potential of this technology in clarifying gene functions in reproductive biology.展开更多
The active DNA demethylation in early embryos is essential for subsequent development. Although the zygotic genome is globally demethylated, the DNA methylation of imprinted regions, part of repeat sequences and some ...The active DNA demethylation in early embryos is essential for subsequent development. Although the zygotic genome is globally demethylated, the DNA methylation of imprinted regions, part of repeat sequences and some gamete-specific regions are maintained. Recent evidence has shown that multiple proteins and biological pathways participate in the regulation of active DNA demethylation, such as TET proteins, DNA repair pathways and DNA methyltransferases. Here we review the recent understanding regarding proteins associated with active DNA demethylation and the regulatory networks controlling the active DNA demethylation in early embryos.展开更多
基金supported by the National Natural Science Foundation of China(31801245,81671425 and 81971357)Key Research&Development Program of Guangzhou Regenerative Medicine and Health Guangdong Laboratory(2019GZR110104001)
文摘One of the main causes of pregnancy failure and fetus abortion is oocyte aneuploidy,which is increased with maternal aging.Numerous possible causes of oocyte aneuploidy in aged women have been proposed,including cross-over formation defect,cohesin loss,spindle deformation,spindle assembly checkpoint malfunction,microtubule-kinetochore attachment failure,kinetochore mis-orientation,mitochondria dysfunction-induced increases in reactive oxygen species,protein over-acetylation,and DNA damage.However,it still needs to be answered if these aneuploidization factors have inherent relations,and how to prevent chromosome aneuploidy in aged oocytes.Epidemiologically,oocyte aneuploidy has been found to be weakly associated with higher homocysteine concentrations,obesity,ionizing radiation and even seasonality.In this review,we summarize the research progress and present an integrated view of oocyte aneuploidization.
基金supported by the Major Basic Research Program(Nos.2012CB944404 and 2011CB944501)the National Natural Science Foundation of China(No.30930065)to Q.Y.S
文摘The mitochondrion is the major energy provider to power sperm motility. In mammals, aside from the nuclear genome, mitochondrial DNA （mtDNA） also contributes to oxidative phosphorylation to impact production of ATP by coding 13 polypeptides. However, the role of sperm mitochondria in fertilization and its final fate after fertilization are still controversial. The viewpoints that sperm bearing more mtDNA will have a better fertilizing capability and that sperm mtDNA is actively eliminated during early embryogenesis are widely accepted. However, this may be not true for several mammalian species, including mice and humans. Here, we review the sperm mitochondria and their mtDNA in sperm functions, and the mechanisms of maternal mitochondrial inheritance in mammals.
基金supported by National Natural Science Foundation of China(32570854)Science and Technology Program of Guangzhou,China(2023A03J0258)Guangdong Basic and Applied Basic Research Foundation,China(2023B1515120027)。
文摘CtBP-interacting protein(CtIP)is known for its multifaceted roles in DNA repair and genomic stability,directing the homologous recombination-mediated DNA double-stranded break repair pathway via DNA end resection,an essential error-free repair process vital for genome stability.Mammalian oocytes are highly prone to DNA damage accumulation due to prolonged G2/prophase arrest.Here,we explore the functions of CtIP in meiotic cell cycle regulation via a mouse oocyte model.Depletion of CtIP by siRNA injection results in delayed germinal vesicle breakdown and failed polar body extrusion.Mechanistically,CtIP deficiency increases DNA damage and decreases the expression and nuclear entry of CCNB1,resulting in marked impairment of meiotic resumption,which can be rescued by exogenous CCNB1 overexpression.Furthermore,depletion of CtIP disrupts microtubule-organizing centers coalescence at spindle poles as indicated by failed accumulation ofγ-tubulin,p-Aurora kinase A,Kif2A,and TPX2,leading to abnormal spindle assembly and prometaphase arrest.These results provide valuable insights into the important roles of CtIP in the G2/M checkpoint and spindle assembly in mouse oocyte meiotic cell cycle regulation.
基金supported by the National Basic Research Program of China(Nos.2011CB944501 and 2012CB944404)the National Natural Science Foundation of China(No. 30930065)
文摘In comparison to conventional knockout technology and in vitro research methods, conditional gene knockout has remarkable advantages. In the past decade, especially during the past five years, conditional knockout approaches have been used to study the regulation of folliculogenesis, follicle growth, oocyte maturation and other major reproductive events. In this review, we summarize the recent findings about folliculogenesis/oogenesis regulation, including the functions of four signaling cascades or glycoprotein domains that have been extensively studied by conditional gene deletion. Several other still fragmented areas of related work are introduced which are awaiting clarification. We have also discussed the future potential of this technology in clarifying gene functions in reproductive biology.
文摘The active DNA demethylation in early embryos is essential for subsequent development. Although the zygotic genome is globally demethylated, the DNA methylation of imprinted regions, part of repeat sequences and some gamete-specific regions are maintained. Recent evidence has shown that multiple proteins and biological pathways participate in the regulation of active DNA demethylation, such as TET proteins, DNA repair pathways and DNA methyltransferases. Here we review the recent understanding regarding proteins associated with active DNA demethylation and the regulatory networks controlling the active DNA demethylation in early embryos.
