Floped(official name Ooep)is specifically and abundantly expressed in mouse oocytes and embryonic stem cells(ESCs).Depletion of Floped from oocytes leads to early embryonic arrest at the 2-cell stage.Although crucial ...Floped(official name Ooep)is specifically and abundantly expressed in mouse oocytes and embryonic stem cells(ESCs).Depletion of Floped from oocytes leads to early embryonic arrest at the 2-cell stage.Although crucial in cleavage stage development,its roles in early embryos as well as in ESCs remain completely unknown.Here,we compared the efficiency of mouse ESC derivation from inner cell mass(ICM)with and without Floped to study its possible roles in mESCs.Derivation rates of mESC from wild-type,heterozygous,and homozygous blastocysts were 33.3%,21.43%,and 3.85%,respectively,indicating that Floped-/-blastocysts had significantly decreased derivation rates.Respective outgrowth appearing rate five days after blastocyst attachment were 83.3%,85.7%,and 15.4%.Morphologically,the outgrowth of ICM from Floped-/-blastocysts appeared severely death three to five days after blastocyst attachment,and the respective derived stem cells showed long-term instability with long-standing epithelial-like colonies.This result suggests a possible role of Floped in the course of ICM-ESCs transition.展开更多
Floped （official name Ooep） is specifically and abundantly expressed in mouse oocytes and embryonic stem cells （ESCs）. Depletion of Floped from oocytes leads to early embryonic arrest at the 2-cell stage. Although...Floped （official name Ooep） is specifically and abundantly expressed in mouse oocytes and embryonic stem cells （ESCs）. Depletion of Floped from oocytes leads to early embryonic arrest at the 2-cell stage. Although crucial in cleavage stage development, its roles in early embryos as well as in ESCs remain completely unknown. Here, we compared the efficiency of mouse ESC derivation from inner cell mass （ICM） with and without Floped to study its possible roles in mESCs. Derivation rates of mESC from wild-type, heterozygous, and homozygous blastocysts were 33.3%, 21.43%, and 3.85%, respectively, indicating that Floped-/- blastocysts had significantly decreased derivation rates. Respective outgrowth appearing rate five days after blastocyst attachment were 83.3%, 85.7%, and 15.4%. Morphologically, the outgrowth of ICM from Floped-/- blastocysts appeared severely death three to five days after blastocyst attachment, and the respective derived stem cells showed long-term instability with long-standing epithelial-like colonies. This result suggests a possible role of Floped in the course of ICM-ESCs transition.展开更多
DNA damage in oocytes can cause infertility and birth defects. DNA double-strand breaks （DSBs） are highly deleterious and can substantially impair genome integrity. Homologous recombination （HR）-mediated DNA DSB r...DNA damage in oocytes can cause infertility and birth defects. DNA double-strand breaks （DSBs） are highly deleterious and can substantially impair genome integrity. Homologous recombination （HR）-mediated DNA DSB repair plays dominant roles in safeguarding oocyte quantity and quality. However, little is known regarding the key players of the HR repair pathway in oocytes. Here, we identified oocyte-specific gene Ooep as a novel key component of the HR repair pathway in mouse oocytes. OOEP was required for efficient ataxia telangiectasia mutated （ATM） kinase activation and Rad51 recombinase （RAD51） focal accumulation at DNA DSBs. Ooep null oocytes were defective in DNA DSB repair and prone to apoptosis upon exogenous DNA damage insults. Moreover, Ooep null oocytes exhibited delayed meiotic maturation. Therefore, OOEP played roles in preserving oocyte quantity and quality by maintaining genome stability. Ooep expression decreased with the advance of maternal age, suggesting its involvement in maternal aging.展开更多
基金This work was supported by the Chinese NSFC grant(31171424)。
文摘Floped(official name Ooep)is specifically and abundantly expressed in mouse oocytes and embryonic stem cells(ESCs).Depletion of Floped from oocytes leads to early embryonic arrest at the 2-cell stage.Although crucial in cleavage stage development,its roles in early embryos as well as in ESCs remain completely unknown.Here,we compared the efficiency of mouse ESC derivation from inner cell mass(ICM)with and without Floped to study its possible roles in mESCs.Derivation rates of mESC from wild-type,heterozygous,and homozygous blastocysts were 33.3%,21.43%,and 3.85%,respectively,indicating that Floped-/-blastocysts had significantly decreased derivation rates.Respective outgrowth appearing rate five days after blastocyst attachment were 83.3%,85.7%,and 15.4%.Morphologically,the outgrowth of ICM from Floped-/-blastocysts appeared severely death three to five days after blastocyst attachment,and the respective derived stem cells showed long-term instability with long-standing epithelial-like colonies.This result suggests a possible role of Floped in the course of ICM-ESCs transition.
文摘Floped （official name Ooep） is specifically and abundantly expressed in mouse oocytes and embryonic stem cells （ESCs）. Depletion of Floped from oocytes leads to early embryonic arrest at the 2-cell stage. Although crucial in cleavage stage development, its roles in early embryos as well as in ESCs remain completely unknown. Here, we compared the efficiency of mouse ESC derivation from inner cell mass （ICM） with and without Floped to study its possible roles in mESCs. Derivation rates of mESC from wild-type, heterozygous, and homozygous blastocysts were 33.3%, 21.43%, and 3.85%, respectively, indicating that Floped-/- blastocysts had significantly decreased derivation rates. Respective outgrowth appearing rate five days after blastocyst attachment were 83.3%, 85.7%, and 15.4%. Morphologically, the outgrowth of ICM from Floped-/- blastocysts appeared severely death three to five days after blastocyst attachment, and the respective derived stem cells showed long-term instability with long-standing epithelial-like colonies. This result suggests a possible role of Floped in the course of ICM-ESCs transition.
基金supported by the National Key Research and Development Program of China(2017YFC1001102)National Natural Science Foundation of China(81760507)
文摘DNA damage in oocytes can cause infertility and birth defects. DNA double-strand breaks （DSBs） are highly deleterious and can substantially impair genome integrity. Homologous recombination （HR）-mediated DNA DSB repair plays dominant roles in safeguarding oocyte quantity and quality. However, little is known regarding the key players of the HR repair pathway in oocytes. Here, we identified oocyte-specific gene Ooep as a novel key component of the HR repair pathway in mouse oocytes. OOEP was required for efficient ataxia telangiectasia mutated （ATM） kinase activation and Rad51 recombinase （RAD51） focal accumulation at DNA DSBs. Ooep null oocytes were defective in DNA DSB repair and prone to apoptosis upon exogenous DNA damage insults. Moreover, Ooep null oocytes exhibited delayed meiotic maturation. Therefore, OOEP played roles in preserving oocyte quantity and quality by maintaining genome stability. Ooep expression decreased with the advance of maternal age, suggesting its involvement in maternal aging.
