Omega-3 polyunsaturated fatty acids(n-3 PUFAs),particularly docosahexaenoic acid(22:6n-3,DHA),play crucial roles in the reproductive health of vertebrates,including humans.Nevertheless,the underlying mechanism related...Omega-3 polyunsaturated fatty acids(n-3 PUFAs),particularly docosahexaenoic acid(22:6n-3,DHA),play crucial roles in the reproductive health of vertebrates,including humans.Nevertheless,the underlying mechanism related to this phenomenon remains largely unknown.In this study,we employed two zebrafish genetic models,i.e.,elovl2^(-/-)mutant as an endogenous DHAdeficient model and fat1(omega-3 desaturase encoding gene)transgenic zebrafish as an endogenous DHA-rich model,to investigate the effects of DHA on oocyte maturation and quality.Results show that the elovl2^(-/-)mutants had much lower fecundity and poorer oocyte quality than the wild-type controls,while the fat1 zebrafish had higher fecundity and better oocyte quality than wildtype controls.DHA deficiency in elovl2^(-/-)embryos led to defects in egg activation,poor microtubule stability,and reduced pregnenolone levels.Further study revealed that DHA promoted pregnenolone synthesis by enhancing transcription of cyp11a1,which encodes the cholesterol side-chain cleavage enzyme,thereby stabilizing microtubule assembly during oogenesis.In turn,the hypothalamic-pituitary-gonadal axis was enhanced by DHA.In conclusion,using two unique genetic models,our findings demonstrate that endogenously synthesized DHA promotes oocyte maturation and quality by promoting pregnenolone production via transcriptional regulation of cyp11a1.展开更多
Zebrafish serve as a valuable model organism for studying germ cell biology and reproductive processes.The AB strain of zebrafish is proposed to exhibit a polygenic sex determination system,where most males initially ...Zebrafish serve as a valuable model organism for studying germ cell biology and reproductive processes.The AB strain of zebrafish is proposed to exhibit a polygenic sex determination system,where most males initially develop juvenile ovaries before committing to male fate.In species with chromosomal sex determination,gonadal somatic cells are recognized as key determinants of germ cell fate.Notably,the loss of germ cells in zebrafish leads to masculinization,implying that germ cells harbor an intrinsic feminization signal.However,the specific signal triggering oogenesis in zebrafish remains unclear.In the present study,we identified foxl2l as an oocyte progenitor-specific gene essential for initiating oogenesis in germ cells.Results showed that foxl2l-knockout zebrafish bypassed the juvenile ovary stage and exclusively developed into fertile males.Further analysis revealed that loss of foxl2l hindered the initiation of oocyte-specific meiosis and prevented entry into oogenesis,leading to premature spermatogenesis during early gonadal development.Furthermore,while mutation of the pro-male gene dmrt1 led to fertile female differentiation,simultaneous disruption of foxl2l in dmrt1 mutants completely blocked oogenesis,with a large proportion of germ cells arrested as germline stem cells,highlighting the crucial role of foxl2l in oogenesis.Overall,this study highlights the unique function of foxl2l as a germ cell-intrinsic gatekeeper of oogenesis in zebrafish.展开更多
Genome-wide association studies(GWASs) are the most widely used method to identify genetic risk loci associated with orofacial clefts(OFC). However, despite the increasing size of cohort, GWASs are still insufficient ...Genome-wide association studies(GWASs) are the most widely used method to identify genetic risk loci associated with orofacial clefts(OFC). However, despite the increasing size of cohort, GWASs are still insufficient to detect all the heritability,suggesting there are more associations under the current stringent statistical threshold. In this study, we obtained an integrated epigenomic dataset based on the chromatin conformation of a human oral epithelial cell line(HIOEC) using RNA-seq, ATAC-seq,H3K27ac Ch IP-seq, and DLO Hi-C. Presumably, this epigenomic dataset could reveal the missing functional variants located in the oral epithelial cell active enhancers/promoters along with their risk target genes, despite relatively less-stringent statistical association with OFC. Taken a non-syndromic cleft palate only(NSCPO) GWAS data of the Chinese Han population as an example, 3664 SNPs that cannot reach the strict significance threshold were subjected to this functional identification pipeline.In total, 254 potential risk SNPs residing in active cis-regulatory elements interacting with 1 718 promoters of oral epitheliumexpressed genes were screened. Gapped k-mer machine learning based on enhancers interacting with epithelium-expressed genes along with in vivo and in vitro reporter assays were employed as functional validation. Among all the potential SNPs, we chose and confirmed that the risk alleles of rs560789 and rs174570 reduced the epithelial-specific enhancer activity by preventing the binding of transcription factors related to epithelial development. In summary, we established chromatin conformation datasets of human oral epithelial cells and provided a framework for testing and understanding how regulatory variants impart risk for clefts.展开更多
We report a facile solution method to form titanium oxide(TiO_(2))nano-flower structure on the titanium(Ti)substrates for realizing good physical sterilization and biocompatibility.We first prepare TiO_(2) nanotubes(N...We report a facile solution method to form titanium oxide(TiO_(2))nano-flower structure on the titanium(Ti)substrates for realizing good physical sterilization and biocompatibility.We first prepare TiO_(2) nanotubes(NT)with a diameter of about 80-100 nm and a length of about 5μm on Ti substrates by anodization,which is utilized as precursor.Then,we employ immersion treatment in different concentrations of phosphoric acid solution at 75℃ for 5 h to realize the transformation from TiO_(2) NT to TiO_(2) nano-flower structure.In addition,we studied the effects of phosphoric acid concentration(1 wt%,2.5 wt%,5 wt% and 10 wt%)on the TiO_(2) nano-flower structure,and the antibacterial properties and biocompatibility of the TiO_(2) nano-flower structure.The results show that TiO_(2) nano-flower structure become larger and thicker with the increase in the phosphoric acid concentration,and the thickness of the coating can reach 6.88μm.Meanwhile,the TiO_(2) nano-flower structure shows good physical sterilization effect,especially for the TiO_(2) nano-flower structure formed in 10 wt%H^(3)PO_(4) solution,the antibacterial rate can reach 95%.In addition,the TiO_(2) nano-flower structure have no toxicity to the osteoblasts and support cell growth.展开更多
Zn-based materials are promising as bone repair materials,but their poor mechanical property and bioactivity as well as low degradation rate render the potential application.Rational structural and material design can...Zn-based materials are promising as bone repair materials,but their poor mechanical property and bioactivity as well as low degradation rate render the potential application.Rational structural and material design can address the concerns.In this study,porous Zn-1 wt.%Mg-3 vol.%β-TCP scaffolds with 40%and 60%preset porosities were fabricated via heating-press sintering using NaCl particles as space holders,and their mechanical properties,in vitro degradation behavior,cytotoxicity and in vivo osteogenic activities were evaluated.The results showed that the actual porosities of the scaffolds were 22%and 50%.Mg exists in the form of Zn 2 Mg and Zn 11 Mg 2,whileβ-TCP evenly distributed in the matrix.The compressive yield strength of scaffolds ranges from approximately 58.46 to 71.04 MPa,which is close to that of cancellous bone.The in vitro degradation tests showed that the corrosion rate of the scaffolds was in the range of about 2.73-4.28 mm y^(-1).Moreover,the scaffolds not only provided great space for osteoblasts adhesion and proliferation in vitro but also possessed favorable degradability and osteogenic activity in vivo.The porous Zn-1 wt.%Mg-3 vol.%β-TCP scaffolds manifest reliable mechanical properties,desirable degradability,and osteogenic activity,which are promising as next-generation bone repair materials.展开更多
Genome editing plays an important role in the research of gene functions,gene correction and cell replacement therapy.Traditionally,genome editing is mainly dependent on the technology of homologous recombination(HR)a...Genome editing plays an important role in the research of gene functions,gene correction and cell replacement therapy.Traditionally,genome editing is mainly dependent on the technology of homologous recombination(HR)and embryonic stem(ES)cell lines in mammals[1].However,genome editing is severely limited by the low efficiency of HR and lack of ES cell lines in most organisms.Recently,the development of zinc finger nucleases(ZFNs),展开更多
The surrogate reproduction technique,such as inter-specific spermatogonial stem cells(SSCs)transplantation(SSCT),provides a powerful tool for production of gametes derived from endangered species or those with desirab...The surrogate reproduction technique,such as inter-specific spermatogonial stem cells(SSCs)transplantation(SSCT),provides a powerful tool for production of gametes derived from endangered species or those with desirable traits.However,generation of genome-edited gametes from a different species or production of gametes from a phylogenetically distant species such as from a different subfamily,by SSCT,has not succeeded.Here,using two small cyprinid fishes from different subfamilies,Chinese rare minnow(gobiocypris rarus,for brief:Gr)and zebrafish(danio rerio),we successfully obtained Gr-derived genome-edited sperm in zebrafish by an optimized SSCT procedure.The transplanted Gr SSCs supported the host gonadal development and underwent normal spermatogenesis,resulting in a reconstructed fertile testis containing Gr spermatids and zebrafish testicular somatic cells.Interestingly,the surrogate spermatozoa resembled those of host zebrafish but not donor Gr in morphology and swimming behavior.When pou5f3 and chd knockout Gr SSCs were transplanted,Gr-derived genome-edited sperm was successfully produced in zebrafish.This is the first report demonstrating surrogate production of gametes from a different subfamily by SSCT,and surrogate production of genome-edited gametes from another species as well.This method is feasible to be applied to future breeding of commercial fish and livestock.展开更多
Aquaculture,the most rapidly growing food production sector,has exhibited tremendous expansion over the past several decades and it currently accounts for more than half of the global fish production for human consump...Aquaculture,the most rapidly growing food production sector,has exhibited tremendous expansion over the past several decades and it currently accounts for more than half of the global fish production for human consumption.To ensure sustainable aquaculture,it is necessary to breed farmed fish species(strains)with valuable economic traits,such as high production,high quality,disease resistance,and stress tolerance.Modem fish genetic breeding techniques largely rely on key processes including understanding the genetic basis of economically important traits to the generation and selection of favorable genotypes.展开更多
Using a nuclear transplantation approach, the integration and expression of the green fluorescent protein (GFP) gene in the embryogenesis of transgenic loach (Misgurnus anguillicaudatus Cantor) have been studied. The ...Using a nuclear transplantation approach, the integration and expression of the green fluorescent protein (GFP) gene in the embryogenesis of transgenic loach (Misgurnus anguillicaudatus Cantor) have been studied. The GFP gene expression is first observed at the gastrula stage, which is consistent with the initiation of cell differentiation of fish embryos. The time course of the foreign gene expression is correlated with the regulatory sequences. The expression efficiency also depends on the gene configuration: the expression of pre-integrating circular plasmid at early embryos is higher than that of the linear plasmid. The integration of the GFP gene is first detected at the blastula stage and lasts for quite a long period. When two types of different plasmids are co-injected into fertilized eggs, the behavior of their integration and expression is not identical.展开更多
The clustered regularly interspaced short palindromic repeats(CRISPR)/Cas9 technology has been widely utilized for knocking out genes involved in various biological processes in zebrafish. Despite this technology is e...The clustered regularly interspaced short palindromic repeats(CRISPR)/Cas9 technology has been widely utilized for knocking out genes involved in various biological processes in zebrafish. Despite this technology is efficient for generating different mutations, one of the main drawbacks is low survival rate during embryogenesis when knocking out some embryonic lethal genes. To overcome this problem, we developed a novel strategy using a combination of CRISPR/Cas9 mediated gene knockout with primordial germ cell(PGC) transplantation(PGCT) to facilitate and speed up the process of zebrafish mutant generation, particularly for embryonic lethal genes. Firstly, we optimized the procedure for CRISPR/Cas9 targeted PGCT by increasing the efficiencies of genome mutation in PGCs and induction of PGC fates in donor embryos for PGCT. Secondly, the optimized CRISPR/Cas9 targeted PGCT was utilized for generation of maternal-zygotic(MZ) mutants of tcf7l1a(gene essential for head development), pou5f3(gene essential for zygotic genome activation) and chd(gene essential for dorsal development) at F1 generation with relatively high efficiency. Finally, we revealed some novel phenotypes in MZ mutants of tcf7l1 a and chd, as MZtcf7l1 a showed elevated neural crest development while MZchd had much severer ventralization than its zygotic counterparts. Therefore, this study presents an efficient and powerful method for generating MZ mutants of embryonic lethal genes in zebrafish. It is also feasible to speed up the genome editing in commercial fishes by utilizing a similar approach by surrogate production of CRISPR/Cas9 targeted germ cells.展开更多
Suppressive regulatory T cells(Treg cells)play a vital role in preventing autoimmunity and restraining excessive immune response to both self-and non-self-antigens.Studies on humans and mice show that the Forkhead box...Suppressive regulatory T cells(Treg cells)play a vital role in preventing autoimmunity and restraining excessive immune response to both self-and non-self-antigens.Studies on humans and mice show that the Forkhead box p3(Foxp3)is a key regulatory gene for the development and function of Treg cells.In zebrafish,Treg cells have been identified by using foxp3a as a reliable marker.However,little is known about the function of foxp3a and Treg cells in gonadal development and sex differentiation.Here,we show that foxp3a is essential for maintaining immune homeostasis in zebrafish testis development.We found that foxp3a was specifically expressed in a subset of T cells in zebrafish testis,while knockout of foxp3a led to deficiency of foxp3a-positive Treg cells in the testis.More than 80%of foxp3a^(-/-)mutants developed as subfertile males,and the rest of the mutants developed as fertile females with decreased ovulation.Further study revealed that foxp3a^(-/-)mutants had a delayed juvenile ovary-to-testis transition in definite males and sex reversal in about half of the definite females,which led to a dominance of later male development.Owing to the absence of foxp3a-positive Treg cells in the differentiating testis of foxp3a^(-/-)mutants,abundant T cells and macrophages expand to disrupt an immunosuppressive milieu,resulting in defective development of germ cells and gonadal somatic cells and leading to development of infertile males.Therefore,our study reveals that foxp3a-positive Treg cells play an essential role in the orchestration of gonadal development and sex differentiation in zebrafish.展开更多
Development of bone fixation devices with excellent corrosion resistance,antibacterial ability,and osteogenic activity is critical for promoting fracture healing.In this study,Zn-incorporated nanopore(NP)layers were p...Development of bone fixation devices with excellent corrosion resistance,antibacterial ability,and osteogenic activity is critical for promoting fracture healing.In this study,Zn-incorporated nanopore(NP)layers were prepared on the NiTi alloy through anodization and hydrothermal treatment.Results show that Zn can be evenly incorporated into the NP layers in the form of ZnTiO_(2).The Zn-incorporated samples exhibit good corrosion resistance and significantly reduce Ni^(2+)release.Meanwhile,the samples can continuously release Zn^(2+),which is responsible for excellent long-term antibacterial ability.Furthermore,the synergetic effect of Zn^(2+) release and nanoporous structure of the NP layers endues the NiTi alloy excellent osteogenic activity,as verified by upregulated alkaline phosphatase activity,secretion of type I collagen,and extracellular matrix mineralization.Therefore,Zn-incorporated Ni-Ti-O NP layers have great potential as biomedical coatings of NiTi-based implant materials.展开更多
Meiosis is essential for evolution and genetic diversity in almost all sexual eukaryotic organisms.The mechanisms of meiotic recombination,such as synapsis,have been extensively investigated.However,it is still unclea...Meiosis is essential for evolution and genetic diversity in almost all sexual eukaryotic organisms.The mechanisms of meiotic recombination,such as synapsis,have been extensively investigated.However,it is still unclear whether signals from the cytoplasm or even from outside of the cell can regulate the meiosis process.Cilia are microtubule-based structures that protrude from the cell surface and function as signaling hubs to sense extracellular signals.Here,we reported an unexpected and critical role of cilia during meiotic recombination.During gametogenesis of zebrafish,cilia were specifically present in the prophase stages of both primary spermatocytes and primary oocytes.By developing a germ cell-specific CRISPR/Cas9 system,we demonstrated that germ cell-specific depletion of ciliary genes resulted in compromised double-strand break repair,reduced crossover formation,and increased germ cell apoptosis.Our study reveals a previously undiscovered role for cilia during meiosis and suggests that extracellular signals may regulate meiotic recombination via this particular organelle.展开更多
The zebrafish has become a very important animal model,not only for developmental biology and genetics,but also for disease modeling and drug discovery.Since the year of 2000,zebrafish research has been rapidly growin...The zebrafish has become a very important animal model,not only for developmental biology and genetics,but also for disease modeling and drug discovery.Since the year of 2000,zebrafish research has been rapidly growing in China,and the laboratories using zebrafish as the main subject have been increasing dramatically（Xie et al.,2015）.For example,the number of participants who attended the Chinese Zebrafish Principle Investigator （PI） Meeting series is 80 in 2012, 150 in 2014, and over 200 this year.展开更多
Zebrafish(Danio rerio)has been used as a promising animal model to study gonadal development and gametogenesis.Although previous studies have identified critical molecules participating in zebrafish gonad differentiat...Zebrafish(Danio rerio)has been used as a promising animal model to study gonadal development and gametogenesis.Although previous studies have identified critical molecules participating in zebrafish gonad differentiation,a landscape view of the biological processes involved in this process is still lacking.Here we isolated intact zebrafish differentiating gonads,at 25 days post-fertilization(dpf)and 30 dpf and conducted RNA-seq analyses on the juvenile gonads that tended to develop into ovaries or testes.Our study demonstrates that the juvenile ovary and testis at 25 dpf and 30 dpf are different at the biological process level.During ovary differentiation,the biological processes related to metabolic activities in the production of energy and maternal substances,RNA degradation,and DNA repair were enriched.During testis differentiation,the biological processes related to cell proliferation,differentiation,and morphogenesis were enriched,with a total of 15 signaling pathways.Notably,we reveal that the immune-related processes are extensively involved in the regulation of testis development.Overall,this study provides a landscape of differentiated biological processes and novel insights into the initiation of sex differentiation in zebrafish.展开更多
Stenting has been widely adopted for the treatment of cardiovascular diseases,but the complications such as in-stent restenosis and late stent thrombosis cannot be completely avoided,which are closely related to endot...Stenting has been widely adopted for the treatment of cardiovascular diseases,but the complications such as in-stent restenosis and late stent thrombosis cannot be completely avoided,which are closely related to endothelial dysfunction and inflammatory response.In the present work,oxide nanosheets were grown on the surface of nearly equiatomic Ni Ti alloy by alkaline corrosion(AC),aiming at yielding favorable endothelial functionality and immune microenvironment.The results show nanosheets mainly composed of TiO_(2),Ni(OH)_(2),and K_(2)TiO_(3)can be grown on the alloy in KOH solution of 2.5–15 M at room temperature.The AC-treated samples significantly promote endothelial cell(EC)functionality such as proliferation,migration,NO production,VEGF secretion,and angiogenesis.In addition,the sample grown in KOH of 15 M can switch macrophages to an anti-inflammatory M2 phenotype and up-regulate the gene expression of VEGF to facilitate EC functionality.These results demonstrate that the nanosheets can directly and indirectly up-regulate EC functionality,possibly leading to rapid re-endothelialization of the stents thus addressing the stent-related complications.展开更多
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(Precision Seed Design and Breeding,XDA24010108)National Natural Science Foundation of China(31972780&31721005)+1 种基金National Key R&D Program of China(2018YFA0801000)State Key Laboratory of Freshwater Ecology and Biotechnology(2019FBZ05)。
文摘Omega-3 polyunsaturated fatty acids(n-3 PUFAs),particularly docosahexaenoic acid(22:6n-3,DHA),play crucial roles in the reproductive health of vertebrates,including humans.Nevertheless,the underlying mechanism related to this phenomenon remains largely unknown.In this study,we employed two zebrafish genetic models,i.e.,elovl2^(-/-)mutant as an endogenous DHAdeficient model and fat1(omega-3 desaturase encoding gene)transgenic zebrafish as an endogenous DHA-rich model,to investigate the effects of DHA on oocyte maturation and quality.Results show that the elovl2^(-/-)mutants had much lower fecundity and poorer oocyte quality than the wild-type controls,while the fat1 zebrafish had higher fecundity and better oocyte quality than wildtype controls.DHA deficiency in elovl2^(-/-)embryos led to defects in egg activation,poor microtubule stability,and reduced pregnenolone levels.Further study revealed that DHA promoted pregnenolone synthesis by enhancing transcription of cyp11a1,which encodes the cholesterol side-chain cleavage enzyme,thereby stabilizing microtubule assembly during oogenesis.In turn,the hypothalamic-pituitary-gonadal axis was enhanced by DHA.In conclusion,using two unique genetic models,our findings demonstrate that endogenously synthesized DHA promotes oocyte maturation and quality by promoting pregnenolone production via transcriptional regulation of cyp11a1.
基金supported by the National Natural Science Foundation of China(32025037)Ministry of Science and Technology of China(2023YFD2401603)+2 种基金Ministry of Agriculture and Rural Affairs of China(NK2022010207)Science and Technology Special Fund of Hainan Province(ZDYF2024XDNY256)Natural Science Foundation of Wuhan。
文摘Zebrafish serve as a valuable model organism for studying germ cell biology and reproductive processes.The AB strain of zebrafish is proposed to exhibit a polygenic sex determination system,where most males initially develop juvenile ovaries before committing to male fate.In species with chromosomal sex determination,gonadal somatic cells are recognized as key determinants of germ cell fate.Notably,the loss of germ cells in zebrafish leads to masculinization,implying that germ cells harbor an intrinsic feminization signal.However,the specific signal triggering oogenesis in zebrafish remains unclear.In the present study,we identified foxl2l as an oocyte progenitor-specific gene essential for initiating oogenesis in germ cells.Results showed that foxl2l-knockout zebrafish bypassed the juvenile ovary stage and exclusively developed into fertile males.Further analysis revealed that loss of foxl2l hindered the initiation of oocyte-specific meiosis and prevented entry into oogenesis,leading to premature spermatogenesis during early gonadal development.Furthermore,while mutation of the pro-male gene dmrt1 led to fertile female differentiation,simultaneous disruption of foxl2l in dmrt1 mutants completely blocked oogenesis,with a large proportion of germ cells arrested as germline stem cells,highlighting the crucial role of foxl2l in oogenesis.Overall,this study highlights the unique function of foxl2l as a germ cell-intrinsic gatekeeper of oogenesis in zebrafish.
基金supported by the National Natural Science Foundation of China(grant numbers:82071077,81771057,and 81400477 to H.L.82181340279,82071110,and 81771066 to Z.C.)+1 种基金“the Fundamental Research Funds for the Central Universities”(no.2042021kf0197)“The Young Top-notch Talent Cultivation Program of Hubei Province”to H.L.
文摘Genome-wide association studies(GWASs) are the most widely used method to identify genetic risk loci associated with orofacial clefts(OFC). However, despite the increasing size of cohort, GWASs are still insufficient to detect all the heritability,suggesting there are more associations under the current stringent statistical threshold. In this study, we obtained an integrated epigenomic dataset based on the chromatin conformation of a human oral epithelial cell line(HIOEC) using RNA-seq, ATAC-seq,H3K27ac Ch IP-seq, and DLO Hi-C. Presumably, this epigenomic dataset could reveal the missing functional variants located in the oral epithelial cell active enhancers/promoters along with their risk target genes, despite relatively less-stringent statistical association with OFC. Taken a non-syndromic cleft palate only(NSCPO) GWAS data of the Chinese Han population as an example, 3664 SNPs that cannot reach the strict significance threshold were subjected to this functional identification pipeline.In total, 254 potential risk SNPs residing in active cis-regulatory elements interacting with 1 718 promoters of oral epitheliumexpressed genes were screened. Gapped k-mer machine learning based on enhancers interacting with epithelium-expressed genes along with in vivo and in vitro reporter assays were employed as functional validation. Among all the potential SNPs, we chose and confirmed that the risk alleles of rs560789 and rs174570 reduced the epithelial-specific enhancer activity by preventing the binding of transcription factors related to epithelial development. In summary, we established chromatin conformation datasets of human oral epithelial cells and provided a framework for testing and understanding how regulatory variants impart risk for clefts.
基金jointly supported by the Four“Batches”Innovation Project of Invigorating Medical through Science and Technology of Shanxi Province(2022XM12)the Central Leading Science and Technology Development Foundation of Shanxi Province(YDZJSX2021A019)+1 种基金the Key Research and Development Program of Shanxi Province(202102130501007)the Natural Science Foundation of Shanxi Province(202103021223102,202203021222127).
文摘We report a facile solution method to form titanium oxide(TiO_(2))nano-flower structure on the titanium(Ti)substrates for realizing good physical sterilization and biocompatibility.We first prepare TiO_(2) nanotubes(NT)with a diameter of about 80-100 nm and a length of about 5μm on Ti substrates by anodization,which is utilized as precursor.Then,we employ immersion treatment in different concentrations of phosphoric acid solution at 75℃ for 5 h to realize the transformation from TiO_(2) NT to TiO_(2) nano-flower structure.In addition,we studied the effects of phosphoric acid concentration(1 wt%,2.5 wt%,5 wt% and 10 wt%)on the TiO_(2) nano-flower structure,and the antibacterial properties and biocompatibility of the TiO_(2) nano-flower structure.The results show that TiO_(2) nano-flower structure become larger and thicker with the increase in the phosphoric acid concentration,and the thickness of the coating can reach 6.88μm.Meanwhile,the TiO_(2) nano-flower structure shows good physical sterilization effect,especially for the TiO_(2) nano-flower structure formed in 10 wt%H^(3)PO_(4) solution,the antibacterial rate can reach 95%.In addition,the TiO_(2) nano-flower structure have no toxicity to the osteoblasts and support cell growth.
基金supported by the Key Research and Development Program of Shanxi Province(No.202102130501007)the Central Leading Science and Technology Development Foundation of Shanxi Province(No.YDZJSX2021A019)+1 种基金the Natural Science Foundation of Shanxi Province(Nos.202103021223102 and 202203021211173)Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering(Nos.2021SX-AT008 and 2021SX-AT009).
文摘Zn-based materials are promising as bone repair materials,but their poor mechanical property and bioactivity as well as low degradation rate render the potential application.Rational structural and material design can address the concerns.In this study,porous Zn-1 wt.%Mg-3 vol.%β-TCP scaffolds with 40%and 60%preset porosities were fabricated via heating-press sintering using NaCl particles as space holders,and their mechanical properties,in vitro degradation behavior,cytotoxicity and in vivo osteogenic activities were evaluated.The results showed that the actual porosities of the scaffolds were 22%and 50%.Mg exists in the form of Zn 2 Mg and Zn 11 Mg 2,whileβ-TCP evenly distributed in the matrix.The compressive yield strength of scaffolds ranges from approximately 58.46 to 71.04 MPa,which is close to that of cancellous bone.The in vitro degradation tests showed that the corrosion rate of the scaffolds was in the range of about 2.73-4.28 mm y^(-1).Moreover,the scaffolds not only provided great space for osteoblasts adhesion and proliferation in vitro but also possessed favorable degradability and osteogenic activity in vivo.The porous Zn-1 wt.%Mg-3 vol.%β-TCP scaffolds manifest reliable mechanical properties,desirable degradability,and osteogenic activity,which are promising as next-generation bone repair materials.
基金supported by the National Natural Science Foundation of China (31325026, 31461163006)Natural Science Foundation of Hubei (2015CFA007)the Chinese Academy of Sciences (XDA08010106)
文摘Genome editing plays an important role in the research of gene functions,gene correction and cell replacement therapy.Traditionally,genome editing is mainly dependent on the technology of homologous recombination(HR)and embryonic stem(ES)cell lines in mammals[1].However,genome editing is severely limited by the low efficiency of HR and lack of ES cell lines in most organisms.Recently,the development of zinc finger nucleases(ZFNs),
基金supported by the National Natural Science Foundation of China(32025037 and 31721005)the National Key R&D Project of China(2018YFA0801000 and 2018YFD0901205)+1 种基金Chinese Academy of Sciences(XDA24010108)State Key Laboratory of Freshwater Ecology and Biotechnology(2019FBZ05)。
文摘The surrogate reproduction technique,such as inter-specific spermatogonial stem cells(SSCs)transplantation(SSCT),provides a powerful tool for production of gametes derived from endangered species or those with desirable traits.However,generation of genome-edited gametes from a different species or production of gametes from a phylogenetically distant species such as from a different subfamily,by SSCT,has not succeeded.Here,using two small cyprinid fishes from different subfamilies,Chinese rare minnow(gobiocypris rarus,for brief:Gr)and zebrafish(danio rerio),we successfully obtained Gr-derived genome-edited sperm in zebrafish by an optimized SSCT procedure.The transplanted Gr SSCs supported the host gonadal development and underwent normal spermatogenesis,resulting in a reconstructed fertile testis containing Gr spermatids and zebrafish testicular somatic cells.Interestingly,the surrogate spermatozoa resembled those of host zebrafish but not donor Gr in morphology and swimming behavior.When pou5f3 and chd knockout Gr SSCs were transplanted,Gr-derived genome-edited sperm was successfully produced in zebrafish.This is the first report demonstrating surrogate production of gametes from a different subfamily by SSCT,and surrogate production of genome-edited gametes from another species as well.This method is feasible to be applied to future breeding of commercial fish and livestock.
文摘Aquaculture,the most rapidly growing food production sector,has exhibited tremendous expansion over the past several decades and it currently accounts for more than half of the global fish production for human consumption.To ensure sustainable aquaculture,it is necessary to breed farmed fish species(strains)with valuable economic traits,such as high production,high quality,disease resistance,and stress tolerance.Modem fish genetic breeding techniques largely rely on key processes including understanding the genetic basis of economically important traits to the generation and selection of favorable genotypes.
文摘Using a nuclear transplantation approach, the integration and expression of the green fluorescent protein (GFP) gene in the embryogenesis of transgenic loach (Misgurnus anguillicaudatus Cantor) have been studied. The GFP gene expression is first observed at the gastrula stage, which is consistent with the initiation of cell differentiation of fish embryos. The time course of the foreign gene expression is correlated with the regulatory sequences. The expression efficiency also depends on the gene configuration: the expression of pre-integrating circular plasmid at early embryos is higher than that of the linear plasmid. The integration of the GFP gene is first detected at the blastula stage and lasts for quite a long period. When two types of different plasmids are co-injected into fertilized eggs, the behavior of their integration and expression is not identical.
基金supported by the National Key R&D Project of China (2018YFA0801000 and 2018YFD0901205)National Natural Science Foundation of China (Nos. 31721005, 31671501 and 31222052)+1 种基金the Youth Innovation Association of CASthe State Key Laboratory of Freshwater Ecology and Biotechnology (No. 2019FBZ05).
文摘The clustered regularly interspaced short palindromic repeats(CRISPR)/Cas9 technology has been widely utilized for knocking out genes involved in various biological processes in zebrafish. Despite this technology is efficient for generating different mutations, one of the main drawbacks is low survival rate during embryogenesis when knocking out some embryonic lethal genes. To overcome this problem, we developed a novel strategy using a combination of CRISPR/Cas9 mediated gene knockout with primordial germ cell(PGC) transplantation(PGCT) to facilitate and speed up the process of zebrafish mutant generation, particularly for embryonic lethal genes. Firstly, we optimized the procedure for CRISPR/Cas9 targeted PGCT by increasing the efficiencies of genome mutation in PGCs and induction of PGC fates in donor embryos for PGCT. Secondly, the optimized CRISPR/Cas9 targeted PGCT was utilized for generation of maternal-zygotic(MZ) mutants of tcf7l1a(gene essential for head development), pou5f3(gene essential for zygotic genome activation) and chd(gene essential for dorsal development) at F1 generation with relatively high efficiency. Finally, we revealed some novel phenotypes in MZ mutants of tcf7l1 a and chd, as MZtcf7l1 a showed elevated neural crest development while MZchd had much severer ventralization than its zygotic counterparts. Therefore, this study presents an efficient and powerful method for generating MZ mutants of embryonic lethal genes in zebrafish. It is also feasible to speed up the genome editing in commercial fishes by utilizing a similar approach by surrogate production of CRISPR/Cas9 targeted germ cells.
基金supported by the National Key Research and Development Program of China(2018YFD0900505 to Y.-A.Z.and 2018YFA0801000 to Y.S.)the National Natural Science Foundation of China(32025037 and 31721005 to Y.S.)。
文摘Suppressive regulatory T cells(Treg cells)play a vital role in preventing autoimmunity and restraining excessive immune response to both self-and non-self-antigens.Studies on humans and mice show that the Forkhead box p3(Foxp3)is a key regulatory gene for the development and function of Treg cells.In zebrafish,Treg cells have been identified by using foxp3a as a reliable marker.However,little is known about the function of foxp3a and Treg cells in gonadal development and sex differentiation.Here,we show that foxp3a is essential for maintaining immune homeostasis in zebrafish testis development.We found that foxp3a was specifically expressed in a subset of T cells in zebrafish testis,while knockout of foxp3a led to deficiency of foxp3a-positive Treg cells in the testis.More than 80%of foxp3a^(-/-)mutants developed as subfertile males,and the rest of the mutants developed as fertile females with decreased ovulation.Further study revealed that foxp3a^(-/-)mutants had a delayed juvenile ovary-to-testis transition in definite males and sex reversal in about half of the definite females,which led to a dominance of later male development.Owing to the absence of foxp3a-positive Treg cells in the differentiating testis of foxp3a^(-/-)mutants,abundant T cells and macrophages expand to disrupt an immunosuppressive milieu,resulting in defective development of germ cells and gonadal somatic cells and leading to development of infertile males.Therefore,our study reveals that foxp3a-positive Treg cells play an essential role in the orchestration of gonadal development and sex differentiation in zebrafish.
基金financially supported by the Fund for Shanxi“1331 Project”Key Innovative Research Team(No.PY201809)Program for the Innovative Talents of Higher Education Institutions of Shanxi(PTIT)Natural Science Foundation of Shanxi Province(No.201801D121093)。
文摘Development of bone fixation devices with excellent corrosion resistance,antibacterial ability,and osteogenic activity is critical for promoting fracture healing.In this study,Zn-incorporated nanopore(NP)layers were prepared on the NiTi alloy through anodization and hydrothermal treatment.Results show that Zn can be evenly incorporated into the NP layers in the form of ZnTiO_(2).The Zn-incorporated samples exhibit good corrosion resistance and significantly reduce Ni^(2+)release.Meanwhile,the samples can continuously release Zn^(2+),which is responsible for excellent long-term antibacterial ability.Furthermore,the synergetic effect of Zn^(2+) release and nanoporous structure of the NP layers endues the NiTi alloy excellent osteogenic activity,as verified by upregulated alkaline phosphatase activity,secretion of type I collagen,and extracellular matrix mineralization.Therefore,Zn-incorporated Ni-Ti-O NP layers have great potential as biomedical coatings of NiTi-based implant materials.
基金National Natural Science Foundation of China(31991194,32025037,and 32125015)Fundamental Research Funds for Central Universities(201941004)State Key Laboratory of Freshwater Ecology and Biotechnology(2019FBZ05).
文摘Meiosis is essential for evolution and genetic diversity in almost all sexual eukaryotic organisms.The mechanisms of meiotic recombination,such as synapsis,have been extensively investigated.However,it is still unclear whether signals from the cytoplasm or even from outside of the cell can regulate the meiosis process.Cilia are microtubule-based structures that protrude from the cell surface and function as signaling hubs to sense extracellular signals.Here,we reported an unexpected and critical role of cilia during meiotic recombination.During gametogenesis of zebrafish,cilia were specifically present in the prophase stages of both primary spermatocytes and primary oocytes.By developing a germ cell-specific CRISPR/Cas9 system,we demonstrated that germ cell-specific depletion of ciliary genes resulted in compromised double-strand break repair,reduced crossover formation,and increased germ cell apoptosis.Our study reveals a previously undiscovered role for cilia during meiosis and suggests that extracellular signals may regulate meiotic recombination via this particular organelle.
文摘The zebrafish has become a very important animal model,not only for developmental biology and genetics,but also for disease modeling and drug discovery.Since the year of 2000,zebrafish research has been rapidly growing in China,and the laboratories using zebrafish as the main subject have been increasing dramatically（Xie et al.,2015）.For example,the number of participants who attended the Chinese Zebrafish Principle Investigator （PI） Meeting series is 80 in 2012, 150 in 2014, and over 200 this year.
基金supported by grants from National Natural Science Foundation of China(31872550,31721005,and 31871305)National Key R&D Program of China(2018YFD0901205)+4 种基金Strategic Priority Research Program of the Chinese Academy of Sciences(XDA24010108)State Key Laboratory of Freshwater Ecology and Biotechnology(2019FBZ05,2020FB08)Fundamental Research Funds for the Central Universities(2662019PY003,2662020PY001)HZAU-AGIS Cooperation Fund(SZYJY2021010)Huazhong Agricultural University Scientific&Technological Self-innovation Foundation(2016RC011).
文摘Zebrafish(Danio rerio)has been used as a promising animal model to study gonadal development and gametogenesis.Although previous studies have identified critical molecules participating in zebrafish gonad differentiation,a landscape view of the biological processes involved in this process is still lacking.Here we isolated intact zebrafish differentiating gonads,at 25 days post-fertilization(dpf)and 30 dpf and conducted RNA-seq analyses on the juvenile gonads that tended to develop into ovaries or testes.Our study demonstrates that the juvenile ovary and testis at 25 dpf and 30 dpf are different at the biological process level.During ovary differentiation,the biological processes related to metabolic activities in the production of energy and maternal substances,RNA degradation,and DNA repair were enriched.During testis differentiation,the biological processes related to cell proliferation,differentiation,and morphogenesis were enriched,with a total of 15 signaling pathways.Notably,we reveal that the immune-related processes are extensively involved in the regulation of testis development.Overall,this study provides a landscape of differentiated biological processes and novel insights into the initiation of sex differentiation in zebrafish.
基金the Fund for Shanxi“1331 Project”Key Innovative Research Team(PY201809)Program for the Innovative Talents of Higher Education Institutions of Shanxi(PTIT)Natural Science Foundation of Shanxi Province(201801D121093)。
文摘Stenting has been widely adopted for the treatment of cardiovascular diseases,but the complications such as in-stent restenosis and late stent thrombosis cannot be completely avoided,which are closely related to endothelial dysfunction and inflammatory response.In the present work,oxide nanosheets were grown on the surface of nearly equiatomic Ni Ti alloy by alkaline corrosion(AC),aiming at yielding favorable endothelial functionality and immune microenvironment.The results show nanosheets mainly composed of TiO_(2),Ni(OH)_(2),and K_(2)TiO_(3)can be grown on the alloy in KOH solution of 2.5–15 M at room temperature.The AC-treated samples significantly promote endothelial cell(EC)functionality such as proliferation,migration,NO production,VEGF secretion,and angiogenesis.In addition,the sample grown in KOH of 15 M can switch macrophages to an anti-inflammatory M2 phenotype and up-regulate the gene expression of VEGF to facilitate EC functionality.These results demonstrate that the nanosheets can directly and indirectly up-regulate EC functionality,possibly leading to rapid re-endothelialization of the stents thus addressing the stent-related complications.
