The fresh postharvest golden needle mushroom(Flammulina velutipes) sporocarp has a high moisture content and crisp texture, but it still has high physiological activity and respiration, leading to senescence and quali...The fresh postharvest golden needle mushroom(Flammulina velutipes) sporocarp has a high moisture content and crisp texture, but it still has high physiological activity and respiration, leading to senescence and quality deterioration.Treatments with 1-methylcyclopropene(1-MCP) and polypropylene(PP) crispers were used to study the changes of lignification and softening of F. velutipes during storage. The main findings were as follows: the crisper packaging could effectively prolong the storage time of F. velutipes;either the 1-MCP treatment, crisper packaging or the combination of the two treatments could significantly inhibit the accumulation of lignin and the decreases in the contents of cellulose and pectin, and had certain inhibitory effects on the activities of enzymes involved in lignification and softening including phenylalanine ammonia-lyase(PAL), cinnamyl alcohol dehydrogenase(CAD), cellulase(Cx), pectin methylesterase(PME) and polygalacturonase(PG). Among them, the inhibitory effect of the crisper packaging was higher than the 1-MCP treatment, while the combination of the two treatments was the best. The results of transmission electron microscopy(TEM) and scanning electron microscopy(SEM) showed that the crisper packaging in combination with the 1-MCP treatment could effectively maintain the integrity and stability of the F. velutipes cellular structure and inhibit the emergence of plasmolysis to prevent cell membrane rupture. The transcription levels showed that the crisper packaging and the combination of the 1-MCP treatment and crisper packing could effectively affect the expression of genes for enzymes related to lignification and softening of F. velutipes. In conclusion, 1-MCP and PP crispers could delay the lignification and softening of F. velutipes during storage.展开更多
Newly emerging technologies are rapidly changing conventional approaches to organ transplantation.In the modern era,the key challenges to transplantation include(1)how to best individualize and possibly eliminate the ...Newly emerging technologies are rapidly changing conventional approaches to organ transplantation.In the modern era,the key challenges to transplantation include(1)how to best individualize and possibly eliminate the need for life-long immunosuppression and(2)how to expand the donor pool suitable for human transplantation.This article aims to provide readers with an updated review of three new technologies that address these challenges.First,single-cell RNA sequencing technology is rapidly evolving and has recently been employed in settings related to transplantation.The new sequencing data indicate an unprecedented cellular heterogeneity within organ transplants,as well as exciting new molecular signatures involved in alloimmune responses.Second,sophisticated nanotechnology platforms provide a means of therapeutically delivering immune modulating reagents to promote transplant tolerance.Tolerogenic nanoparticles with regulatory molecules and donor antigens are capable of targeting host immune responses with tremendous precision,which,in some cases,results in donor-specific tolerance.Third,CRISPR/Cas9 gene editing technology has the potential to precisely remove immunogenic molecules while inserting desirable regulatory molecules.This technology is particularly useful in generating genetically modified pigs for xenotransplantation to solve the issue of the shortage of human organs.Collectively,these new technologies are positioning the transplant community for major breakthroughs that will significantly advance transplant medicine.展开更多
Meiosis-arrest female 1（MARF1） is a recently identified key oogenic regulator essential for the maintenance of female fertility and genome integrity in mice. However, the detailed functions and the underlying mechan...Meiosis-arrest female 1（MARF1） is a recently identified key oogenic regulator essential for the maintenance of female fertility and genome integrity in mice. However, the detailed functions and the underlying mechanisms of MARF1 remain elusive. Here, in an attempt to create a mouse model expressing fluorescent protein-tagged MARF1 to facilitate further exploration of the roles of MARF1 in oocytes, we produced a Marf1-eGFP knockin（KI） mouse line in which the C-terminal structure and function of MARF1 were interfered by its fusing eGFP peptide. Using these Marfl-eGFP-KI mice, we revealed, unexpectedly, the functions of MARF1 in the control of oocyte meiotic division.We found that the Marfl-eGFP-KI females ovulated mature oocytes with severe meiotic and developmental defects,and thus were infertile. Moreover, meiotic reinitiation was delayed while meiotic completion was accelerated in the KI-oocytes, which was coincident with the increased incidence of oocyte aneuploidy. Therefore, MARF1 is indispensable for maintaining the fidelity of homolog segregation during oocyte maturation, and this function relies on its C-terminal domains.展开更多
基金supported by the National Natural Science Foundation of China(31471576)the Chongqing Science and Technology Commission,China(cstc2015shmszx80019)。
文摘The fresh postharvest golden needle mushroom(Flammulina velutipes) sporocarp has a high moisture content and crisp texture, but it still has high physiological activity and respiration, leading to senescence and quality deterioration.Treatments with 1-methylcyclopropene(1-MCP) and polypropylene(PP) crispers were used to study the changes of lignification and softening of F. velutipes during storage. The main findings were as follows: the crisper packaging could effectively prolong the storage time of F. velutipes;either the 1-MCP treatment, crisper packaging or the combination of the two treatments could significantly inhibit the accumulation of lignin and the decreases in the contents of cellulose and pectin, and had certain inhibitory effects on the activities of enzymes involved in lignification and softening including phenylalanine ammonia-lyase(PAL), cinnamyl alcohol dehydrogenase(CAD), cellulase(Cx), pectin methylesterase(PME) and polygalacturonase(PG). Among them, the inhibitory effect of the crisper packaging was higher than the 1-MCP treatment, while the combination of the two treatments was the best. The results of transmission electron microscopy(TEM) and scanning electron microscopy(SEM) showed that the crisper packaging in combination with the 1-MCP treatment could effectively maintain the integrity and stability of the F. velutipes cellular structure and inhibit the emergence of plasmolysis to prevent cell membrane rupture. The transcription levels showed that the crisper packaging and the combination of the 1-MCP treatment and crisper packing could effectively affect the expression of genes for enzymes related to lignification and softening of F. velutipes. In conclusion, 1-MCP and PP crispers could delay the lignification and softening of F. velutipes during storage.
基金This work was supported by grants from the National Institutes of Health(R01 EB009910)(A.D.and X.L.)the Chinese Scholarship Council(S.Y.).
文摘Newly emerging technologies are rapidly changing conventional approaches to organ transplantation.In the modern era,the key challenges to transplantation include(1)how to best individualize and possibly eliminate the need for life-long immunosuppression and(2)how to expand the donor pool suitable for human transplantation.This article aims to provide readers with an updated review of three new technologies that address these challenges.First,single-cell RNA sequencing technology is rapidly evolving and has recently been employed in settings related to transplantation.The new sequencing data indicate an unprecedented cellular heterogeneity within organ transplants,as well as exciting new molecular signatures involved in alloimmune responses.Second,sophisticated nanotechnology platforms provide a means of therapeutically delivering immune modulating reagents to promote transplant tolerance.Tolerogenic nanoparticles with regulatory molecules and donor antigens are capable of targeting host immune responses with tremendous precision,which,in some cases,results in donor-specific tolerance.Third,CRISPR/Cas9 gene editing technology has the potential to precisely remove immunogenic molecules while inserting desirable regulatory molecules.This technology is particularly useful in generating genetically modified pigs for xenotransplantation to solve the issue of the shortage of human organs.Collectively,these new technologies are positioning the transplant community for major breakthroughs that will significantly advance transplant medicine.
基金supported by National Basic Research Program (973) from Ministry of Science and Technology of the People's Republic of China (grant numbers 2014CB943200, 2013CB945500)National NaturalScience Foundation of China (grant numbers 31471351, 31271538)Natural Science Foundation of Jiangsu Province (grant number BK20140061)to YQ Su
文摘Meiosis-arrest female 1（MARF1） is a recently identified key oogenic regulator essential for the maintenance of female fertility and genome integrity in mice. However, the detailed functions and the underlying mechanisms of MARF1 remain elusive. Here, in an attempt to create a mouse model expressing fluorescent protein-tagged MARF1 to facilitate further exploration of the roles of MARF1 in oocytes, we produced a Marf1-eGFP knockin（KI） mouse line in which the C-terminal structure and function of MARF1 were interfered by its fusing eGFP peptide. Using these Marfl-eGFP-KI mice, we revealed, unexpectedly, the functions of MARF1 in the control of oocyte meiotic division.We found that the Marfl-eGFP-KI females ovulated mature oocytes with severe meiotic and developmental defects,and thus were infertile. Moreover, meiotic reinitiation was delayed while meiotic completion was accelerated in the KI-oocytes, which was coincident with the increased incidence of oocyte aneuploidy. Therefore, MARF1 is indispensable for maintaining the fidelity of homolog segregation during oocyte maturation, and this function relies on its C-terminal domains.
