Parthenogenetic embryonic stem cells have pluripotent differentiation potentials, akin to fertilized embryo-derived embryonic stem cells. The aim of this study was to compare the neuronal differentiation potential of ...Parthenogenetic embryonic stem cells have pluripotent differentiation potentials, akin to fertilized embryo-derived embryonic stem cells. The aim of this study was to compare the neuronal differentiation potential of parthenogenetic and fertilized embryo-derived embryonic stem cells. Before differentiation, karyotype analysis was performed, with normal karyotypes detected in both parthenogenetic and fertilized embryo-derived embryonic stem cells. Sex chromosomes were identified as XX. Immunocytochemistry and quantitative real-time PCR detected high expression of the pluripotent gene, Oct4, at both the mRNA and protein levels, indicating pluripotent differentiation potential of the two embryonic stem cell subtypes. Embryonic stern cells were induced with retinoic acid to form embryoid bodies, and then dispersed into single cells. Single cells were differentiated in N2 differentiation medium for 9 days. Immunocytochemistry showed parthenogenetic and fertilized embryo-derived embryonic stem cells both express the neuronal cell markers nestin, ~lll-tubulin and myelin basic protein. Quantitative real-time PCR found expression of neuregenesis related genes (Sox-1, Nestin, GABA, Pax6, Zic5 and Pitxl) in both types of embryonic stem cells, and Oct4 expression was significantly decreased. Nestin and Pax6 expression in parthenogenetic embryonic stem cells was significantly higher than that in fertilized embryo-derived embryonic stem cells. Thus, our experimental findings indicate that parthenogenetic embryonic stem cells have stronger neuronal differentiation potential than fertilized embryo-derived embryonic stem cells.展开更多
Tumors are one of the leading causes to death in pet dogs among diseases. The tumor incidence of pet dogs has been increasing, raising widespread concern. In this study, retrospective analysis was performed with 246 t...Tumors are one of the leading causes to death in pet dogs among diseases. The tumor incidence of pet dogs has been increasing, raising widespread concern. In this study, retrospective analysis was performed with 246 tumor cases registered in Xi’an Animal Hospital, Northwest A&F University from 2009 to 2018. Correlations of sex, age and breed with tumor incidences were evaluated. The results showed that reproductive system tumors occupied the highest proportion (39.84%), followed by cutaneous tumors (28.05%), digestive tumors (18.70%) and ocular tumor (4.47%). Among the reproductive system tumors, breast tumors are the most common tumor in female pet dogs, especially for Pekingese (11.43%). Female dogs with high susceptibility to breast tumors were at the ages of 6–18 years old. As far as cutaneous tumors were concerned, the male pet dogs at all ages, particularly Golden Retrievers (17.39%), showed a high incidence. By contrast, male Samoyed aged from 4 to 13 years had the highest incidence (15.22%) of digestive tumors. In addition, pet dogs with ocular tumors mainly happened at the ages of 0–1 years and 6–13 years. Collectively, our findings are significant to develop effective measures of medical surveillance for pet dogs’ health and will provide insights for comparative oncology.展开更多
The rumen is the hallmark organ of ruminants and hosts a diverse ecosystem of microorganisms that facilitates efficient digestion of plant fibers.We analyzed 897 transcriptomes from three Cetartiodactyla lineages:rumi...The rumen is the hallmark organ of ruminants and hosts a diverse ecosystem of microorganisms that facilitates efficient digestion of plant fibers.We analyzed 897 transcriptomes from three Cetartiodactyla lineages:ruminants,camels and cetaceans,as well as data from ruminant comparative genomics and functional assays to explore the genetic basis of rumen functional innovations.We identified genes with relatively high expression in the rumen,of which many appeared to be recruited from other tissues.These genes show functional enrichment in ketone body metabolism,regulation of microbial community,and epithelium absorption,which are the most prominent biological processes involved in rumen innovations.Several modes of genetic change underlying rumen functional innovations were uncovered,including coding mutations,genes newly evolved,and changes of regulatory elements.We validated that the key ketogenesis rate-limiting gene(HMGCS2)with five ruminant-specific mutations was under positive selection and exhibits higher synthesis activity than those of other mammals.Two newly evolved genes(LYZ1 and DEFB1)are resistant to Gram-positive bacteria and thereby may regulate microbial community equilibrium.Furthermore,we confirmed that the changes of regulatory elements accounted for the majority of rumen gene recruitment.These results greatly improve our understanding of rumen evolution and organ evo-devo in general.展开更多
Pluripotent stem cells(PSCs) are characterized by their capacity for high self-renewal and multiple differentiation potential and include embryonic stem cells, embryonic germ cells and induced PSCs. PSCs provide a ver...Pluripotent stem cells(PSCs) are characterized by their capacity for high self-renewal and multiple differentiation potential and include embryonic stem cells, embryonic germ cells and induced PSCs. PSCs provide a very suitable model for the studies of human diseases, drugs screening, regenerative medicine and developmental biology research. Pigs are considered as an ideal model for preclinical development of human xenotransplantation, therapeutic approaches and regenerative medicine because of their size and physiological similarity to humans. However, lack of knowledge about the derivation, characterization and pluripotency mechanisms of porcine PSCs hinders progress in these biotechnologies. In this review, we discuss the latest progress on porcine PSCs generation, evaluation criteria for pluripotency, the scienti?c and technical questions arising from these studies. We also introduce our perspectives on porcine PSC research, in the hope of providing new ideas for generating naive porcine PSCs and animal breeding.展开更多
Current measures mainly focus on how melatonin reduces physiological heat stress in animals,but its effects on reproductive damage to male dairy goats have been neglected.This study aimed to determine the protective e...Current measures mainly focus on how melatonin reduces physiological heat stress in animals,but its effects on reproductive damage to male dairy goats have been neglected.This study aimed to determine the protective effect of melatonin on male reproduction during heat stress in dairy goats and to further explore its mechanisms.A natural heat stress model of Saanen dairy goats was used to assess testicular tissue damage 7days after heat stress and to examine semen quality changes during a spermatogenic cycle.RNA-seq,Western blot,RT–qPCR,and immunofluo-rescence staining were used to explore the mechanism by which melatonin protects against heat stress-induced reproductive damage and to validate the results.The data suggested that melatonin significantly alleviated the heat stress-induced decrease in sperm quality,protected varicose tubule structure,reduced the levels of heat shock proteins and apoptotic proteins and protected the spermatocytes and round spermatozoa,which are mainly affected by heat stress.RNA-seq results suggest that melatonin inhibits the PI3K/AKT signaling pathway,reduces the level of p-AKT,and promotes elevated BCL-2.In addition,melatonin treatment could upregulate the gene expression of MT2 which was downregulated by heat stress and improve the change in extracellular matrix components and restore serum testosterone levels.Our results suggest that melatonin can protect against testicular and spermatogenic cell damage and improve semen quality in male dairy goats under heat stress.This study provides an important reference for subsequent studies on the molecular mechanisms of melatonin in protecting male reproductive processes under heat stress and using exogenous melatonin to prevent heat stress.展开更多
Primordial germ cells(PGCs) are regarded as unipotent cells that can produce only either spermatogonia or oocytes. However, PGCs can be converted into the pluripotent state by ?rst dedifferentiation to embryonic germ ...Primordial germ cells(PGCs) are regarded as unipotent cells that can produce only either spermatogonia or oocytes. However, PGCs can be converted into the pluripotent state by ?rst dedifferentiation to embryonic germ cells and then by reprogramming to induce them to become pluripotent stem cells(iPSCs). These two stages can be completely implemented with mouse cells. However, authentic porcine iPSCs have not been established.Here, we discuss recent advances in the stem cell ?eld for obtaining iPSCs from PGCs. This knowledge will provide some clues which will contribute to the regulation of reprogramming to pluripotency in farm species.展开更多
基金supported by the National Natural Science Foundation of China,No. 30900155 and 81070496the Research Foundation of Education Bureau of Shaanxi Province,China,No. 09JK785+1 种基金Foundation of Interdisciplinary for Postgraduates from Northwest University,No. 08YJC22the Key Laboratory Funding of Northwestern University,Shaanxi Province in China
文摘Parthenogenetic embryonic stem cells have pluripotent differentiation potentials, akin to fertilized embryo-derived embryonic stem cells. The aim of this study was to compare the neuronal differentiation potential of parthenogenetic and fertilized embryo-derived embryonic stem cells. Before differentiation, karyotype analysis was performed, with normal karyotypes detected in both parthenogenetic and fertilized embryo-derived embryonic stem cells. Sex chromosomes were identified as XX. Immunocytochemistry and quantitative real-time PCR detected high expression of the pluripotent gene, Oct4, at both the mRNA and protein levels, indicating pluripotent differentiation potential of the two embryonic stem cell subtypes. Embryonic stern cells were induced with retinoic acid to form embryoid bodies, and then dispersed into single cells. Single cells were differentiated in N2 differentiation medium for 9 days. Immunocytochemistry showed parthenogenetic and fertilized embryo-derived embryonic stem cells both express the neuronal cell markers nestin, ~lll-tubulin and myelin basic protein. Quantitative real-time PCR found expression of neuregenesis related genes (Sox-1, Nestin, GABA, Pax6, Zic5 and Pitxl) in both types of embryonic stem cells, and Oct4 expression was significantly decreased. Nestin and Pax6 expression in parthenogenetic embryonic stem cells was significantly higher than that in fertilized embryo-derived embryonic stem cells. Thus, our experimental findings indicate that parthenogenetic embryonic stem cells have stronger neuronal differentiation potential than fertilized embryo-derived embryonic stem cells.
基金This research was funded by grants from the Xi’an Northwest Agriculture and Forestry University Animal Hospital Co.,Ltd.(K4040121234)the State Key Laboratory of Genetically Engineered Veterinary Vaccines(AGVSKL-ZY-201802,AGVSKL-ZD-202009)the NWAFU Fundamental Research Funds for the Central Universities(2452019055).
文摘Tumors are one of the leading causes to death in pet dogs among diseases. The tumor incidence of pet dogs has been increasing, raising widespread concern. In this study, retrospective analysis was performed with 246 tumor cases registered in Xi’an Animal Hospital, Northwest A&F University from 2009 to 2018. Correlations of sex, age and breed with tumor incidences were evaluated. The results showed that reproductive system tumors occupied the highest proportion (39.84%), followed by cutaneous tumors (28.05%), digestive tumors (18.70%) and ocular tumor (4.47%). Among the reproductive system tumors, breast tumors are the most common tumor in female pet dogs, especially for Pekingese (11.43%). Female dogs with high susceptibility to breast tumors were at the ages of 6–18 years old. As far as cutaneous tumors were concerned, the male pet dogs at all ages, particularly Golden Retrievers (17.39%), showed a high incidence. By contrast, male Samoyed aged from 4 to 13 years had the highest incidence (15.22%) of digestive tumors. In addition, pet dogs with ocular tumors mainly happened at the ages of 0–1 years and 6–13 years. Collectively, our findings are significant to develop effective measures of medical surveillance for pet dogs’ health and will provide insights for comparative oncology.
基金supported by the National Natural Science Foundation of China(31822052,31572381)the National Thousand Youth Talents Plan to Y.J.+3 种基金National Natural Science Foundation of China(31660644)to S.H.National Natural Science Foundation of China(41422604)to S.L.The Villum Foundation(VKR 023447)the Independent Research Fund Denmark(8049-00098B)。
文摘The rumen is the hallmark organ of ruminants and hosts a diverse ecosystem of microorganisms that facilitates efficient digestion of plant fibers.We analyzed 897 transcriptomes from three Cetartiodactyla lineages:ruminants,camels and cetaceans,as well as data from ruminant comparative genomics and functional assays to explore the genetic basis of rumen functional innovations.We identified genes with relatively high expression in the rumen,of which many appeared to be recruited from other tissues.These genes show functional enrichment in ketone body metabolism,regulation of microbial community,and epithelium absorption,which are the most prominent biological processes involved in rumen innovations.Several modes of genetic change underlying rumen functional innovations were uncovered,including coding mutations,genes newly evolved,and changes of regulatory elements.We validated that the key ketogenesis rate-limiting gene(HMGCS2)with five ruminant-specific mutations was under positive selection and exhibits higher synthesis activity than those of other mammals.Two newly evolved genes(LYZ1 and DEFB1)are resistant to Gram-positive bacteria and thereby may regulate microbial community equilibrium.Furthermore,we confirmed that the changes of regulatory elements accounted for the majority of rumen gene recruitment.These results greatly improve our understanding of rumen evolution and organ evo-devo in general.
基金funded by the National Key Research and Development Program of China-Stem Cell and Translational Research (2016YFA0100200)
文摘Pluripotent stem cells(PSCs) are characterized by their capacity for high self-renewal and multiple differentiation potential and include embryonic stem cells, embryonic germ cells and induced PSCs. PSCs provide a very suitable model for the studies of human diseases, drugs screening, regenerative medicine and developmental biology research. Pigs are considered as an ideal model for preclinical development of human xenotransplantation, therapeutic approaches and regenerative medicine because of their size and physiological similarity to humans. However, lack of knowledge about the derivation, characterization and pluripotency mechanisms of porcine PSCs hinders progress in these biotechnologies. In this review, we discuss the latest progress on porcine PSCs generation, evaluation criteria for pluripotency, the scienti?c and technical questions arising from these studies. We also introduce our perspectives on porcine PSC research, in the hope of providing new ideas for generating naive porcine PSCs and animal breeding.
基金supported by the natural sciences foundation of China(32072815)the technology innovation leading program of Shaanxi province(2020QFY10)+1 种基金the program of Shaanxi province science and technology innovation team(2019TD-036)the fundamental research funds for the central universities(2452020157).
文摘Current measures mainly focus on how melatonin reduces physiological heat stress in animals,but its effects on reproductive damage to male dairy goats have been neglected.This study aimed to determine the protective effect of melatonin on male reproduction during heat stress in dairy goats and to further explore its mechanisms.A natural heat stress model of Saanen dairy goats was used to assess testicular tissue damage 7days after heat stress and to examine semen quality changes during a spermatogenic cycle.RNA-seq,Western blot,RT–qPCR,and immunofluo-rescence staining were used to explore the mechanism by which melatonin protects against heat stress-induced reproductive damage and to validate the results.The data suggested that melatonin significantly alleviated the heat stress-induced decrease in sperm quality,protected varicose tubule structure,reduced the levels of heat shock proteins and apoptotic proteins and protected the spermatocytes and round spermatozoa,which are mainly affected by heat stress.RNA-seq results suggest that melatonin inhibits the PI3K/AKT signaling pathway,reduces the level of p-AKT,and promotes elevated BCL-2.In addition,melatonin treatment could upregulate the gene expression of MT2 which was downregulated by heat stress and improve the change in extracellular matrix components and restore serum testosterone levels.Our results suggest that melatonin can protect against testicular and spermatogenic cell damage and improve semen quality in male dairy goats under heat stress.This study provides an important reference for subsequent studies on the molecular mechanisms of melatonin in protecting male reproductive processes under heat stress and using exogenous melatonin to prevent heat stress.
基金supported by the National Basic Research Program of China (2016YFA0100203)the National Natural Science Foundation of China (31572399, 31272518)
文摘Primordial germ cells(PGCs) are regarded as unipotent cells that can produce only either spermatogonia or oocytes. However, PGCs can be converted into the pluripotent state by ?rst dedifferentiation to embryonic germ cells and then by reprogramming to induce them to become pluripotent stem cells(iPSCs). These two stages can be completely implemented with mouse cells. However, authentic porcine iPSCs have not been established.Here, we discuss recent advances in the stem cell ?eld for obtaining iPSCs from PGCs. This knowledge will provide some clues which will contribute to the regulation of reprogramming to pluripotency in farm species.