Spermatogenesis is a fundamental process that requires a tightly controlled epigenetic event in spermatogonial stem cells(SSCs).The mechanisms underlying the transition from SSCs to sperm are largely unknown.Most stud...Spermatogenesis is a fundamental process that requires a tightly controlled epigenetic event in spermatogonial stem cells(SSCs).The mechanisms underlying the transition from SSCs to sperm are largely unknown.Most studies utilize gene knockout mice to explain the mechanisms.However,the production of genetically engineered mice is costly and time-consuming.In this study,we presented a convenient research strategy using an RNA interference(RNAi)and testicular transplantation approach.Histone H3 lysine 9(H3K9)methylation was dynamically regulated during spermatogenesis.As Jumonji domain-containing protein 1A(JMJD1A)and Jumonji domain-containing protein 2C(JMJD2C)demethylases catalyze histone H3 lysine 9 dimethylation(H3K9me2),we firstly analyzed the expression profile of the two demethylases and then investigated their function.Using the convenient research strategy,we showed that normal spermatogenesis is disrupted due to the downregulated expression of both demethylases.These results suggest that this strategy might be a simple and alternative approach for analyzing spermatogenesis relative to the gene knockout mice strategy.展开更多
In the mammalian genome,most CpGs are methylated.However,CpGs within the CpG islands(CGIs)are largely unmethylated,which are important for gene expression regulation.The mechanism underlying the low methylation levels...In the mammalian genome,most CpGs are methylated.However,CpGs within the CpG islands(CGIs)are largely unmethylated,which are important for gene expression regulation.The mechanism underlying the low methylation levels at CGIs remains largely elusive.KDM2 proteins(KDM2A and KDM2B)are H3K36me2 demethylases known to bind specifically at CGIs.Here,we report that depletion of each or both KDM2 proteins,or mutation of all their JmjC domains that harbor the H3K36me2 demethylation activity,leads to an increase in DNA methylation at selective CGIs.The Kdm2a/2b double knockout shows a stronger increase in DNA methylation compared with the single mutant of Kdm2a or Kdm2b,indicating that KDM2A and KDM2B redundantly regulate DNA methylation at CGIs.In addition,the increase of CGI DNA methylation upon mutations of KDM2 proteins is associated with the chromatin environment.Our findings reveal that KDM2A and KDM2B function redundantly in regulating DNA methylation at a subset of CGIs in an H3K36me2 demethylation-dependent manner.展开更多
在MP2水平上采用6-311G基组计算了van der Waals复合物X…H2O(X=Li,Na,K)的非线性光学性质(μα,β),讨论了基组效应和电子相关效应对计算结果的贡献．在MP2／6-311++G(2df,2pd)水平上计算得到的三个复合物分子X(X=Li,Na,K)…H2O的非线...在MP2水平上采用6-311G基组计算了van der Waals复合物X…H2O(X=Li,Na,K)的非线性光学性质(μα,β),讨论了基组效应和电子相关效应对计算结果的贡献．在MP2／6-311++G(2df,2pd)水平上计算得到的三个复合物分子X(X=Li,Na,K)…H2O的非线性光学性质．结果表明,三种复合物分子均具有巨大的一阶超极化率,其中最外层电子的弥散特性对一阶超极化率有很大的影响．展开更多
Using a reversed-phase microemulsion polymerization method, polyoxometalates(POMs) CoW 11Ti loaded starch nanoparticles were prepared and structurally characterized by elemental analyses, IR, UV-Vis and ESR spectrosco...Using a reversed-phase microemulsion polymerization method, polyoxometalates(POMs) CoW 11Ti loaded starch nanoparticles were prepared and structurally characterized by elemental analyses, IR, UV-Vis and ESR spectroscopy. The particle size of CoW 11Ti/starch was estimated by transmission electron microscope(TEM) and the size ranges by a 1000HSA MALVIRN Zetasizer instrument. The result shows that the polyoxometalate retained the parent structure after encapsulated by starch microspheres, which are able to enhance the stability and antitumoral activity of POMs and decrease the toxicity of POMs as well.展开更多
The new complex, [K2(TNR)(H2O)]n, was prepared by reacting 2,4,6 trinitroresorcinol with potassium hyd roxide. Its crystal structure was determined by X ray single crystal diffraction analysis. The crystalline belongs...The new complex, [K2(TNR)(H2O)]n, was prepared by reacting 2,4,6 trinitroresorcinol with potassium hyd roxide. Its crystal structure was determined by X ray single crystal diffraction analysis. The crystalline belongs to triclinic with space group .Its unit cell parameters are as follows:a=0.6993(1)nm, b=0.9474(2)nm, c=0.9791(1)nm, α=115.28(1)°, β=107.86(1)°, γ=95.94(1)°, V=0.53717(15)nm3, Z=2, Dc=2.098g ·cm-3, F(000)=340. The two potassium ions have different coordination numbers of which are 8 and 9, respectively. The thermal decomposition mechanism of the complex was studied by using DSC, TG GTG and FT IR techniques. The existence of KNC in the residue is shown in FT IR. CCDC: 204441.展开更多
基金financially supported by the Shandong Provincial Natural Science Foundation(No.ZR2021QC182).
文摘Spermatogenesis is a fundamental process that requires a tightly controlled epigenetic event in spermatogonial stem cells(SSCs).The mechanisms underlying the transition from SSCs to sperm are largely unknown.Most studies utilize gene knockout mice to explain the mechanisms.However,the production of genetically engineered mice is costly and time-consuming.In this study,we presented a convenient research strategy using an RNA interference(RNAi)and testicular transplantation approach.Histone H3 lysine 9(H3K9)methylation was dynamically regulated during spermatogenesis.As Jumonji domain-containing protein 1A(JMJD1A)and Jumonji domain-containing protein 2C(JMJD2C)demethylases catalyze histone H3 lysine 9 dimethylation(H3K9me2),we firstly analyzed the expression profile of the two demethylases and then investigated their function.Using the convenient research strategy,we showed that normal spermatogenesis is disrupted due to the downregulated expression of both demethylases.These results suggest that this strategy might be a simple and alternative approach for analyzing spermatogenesis relative to the gene knockout mice strategy.
基金supported by the National Natural Science Foundation of China(32070607)the National Key Research and Development Program of China(2020YFA0804000)the CAS Project for Young Scientists in Basic Research(YSBR-012).
文摘In the mammalian genome,most CpGs are methylated.However,CpGs within the CpG islands(CGIs)are largely unmethylated,which are important for gene expression regulation.The mechanism underlying the low methylation levels at CGIs remains largely elusive.KDM2 proteins(KDM2A and KDM2B)are H3K36me2 demethylases known to bind specifically at CGIs.Here,we report that depletion of each or both KDM2 proteins,or mutation of all their JmjC domains that harbor the H3K36me2 demethylation activity,leads to an increase in DNA methylation at selective CGIs.The Kdm2a/2b double knockout shows a stronger increase in DNA methylation compared with the single mutant of Kdm2a or Kdm2b,indicating that KDM2A and KDM2B redundantly regulate DNA methylation at CGIs.In addition,the increase of CGI DNA methylation upon mutations of KDM2 proteins is associated with the chromatin environment.Our findings reveal that KDM2A and KDM2B function redundantly in regulating DNA methylation at a subset of CGIs in an H3K36me2 demethylation-dependent manner.
文摘在MP2水平上采用6-311G基组计算了van der Waals复合物X…H2O(X=Li,Na,K)的非线性光学性质(μα,β),讨论了基组效应和电子相关效应对计算结果的贡献．在MP2／6-311++G(2df,2pd)水平上计算得到的三个复合物分子X(X=Li,Na,K)…H2O的非线性光学性质．结果表明,三种复合物分子均具有巨大的一阶超极化率,其中最外层电子的弥散特性对一阶超极化率有很大的影响．
文摘Using a reversed-phase microemulsion polymerization method, polyoxometalates(POMs) CoW 11Ti loaded starch nanoparticles were prepared and structurally characterized by elemental analyses, IR, UV-Vis and ESR spectroscopy. The particle size of CoW 11Ti/starch was estimated by transmission electron microscope(TEM) and the size ranges by a 1000HSA MALVIRN Zetasizer instrument. The result shows that the polyoxometalate retained the parent structure after encapsulated by starch microspheres, which are able to enhance the stability and antitumoral activity of POMs and decrease the toxicity of POMs as well.
文摘The new complex, [K2(TNR)(H2O)]n, was prepared by reacting 2,4,6 trinitroresorcinol with potassium hyd roxide. Its crystal structure was determined by X ray single crystal diffraction analysis. The crystalline belongs to triclinic with space group .Its unit cell parameters are as follows:a=0.6993(1)nm, b=0.9474(2)nm, c=0.9791(1)nm, α=115.28(1)°, β=107.86(1)°, γ=95.94(1)°, V=0.53717(15)nm3, Z=2, Dc=2.098g ·cm-3, F(000)=340. The two potassium ions have different coordination numbers of which are 8 and 9, respectively. The thermal decomposition mechanism of the complex was studied by using DSC, TG GTG and FT IR techniques. The existence of KNC in the residue is shown in FT IR. CCDC: 204441.
