Tilia amurensis is an economically valuable broadleaf tree species in Northeast China.The production of highqualityT.amurensis varieties at commercial scales has been greatly limited by the low germination rates.There...Tilia amurensis is an economically valuable broadleaf tree species in Northeast China.The production of highqualityT.amurensis varieties at commercial scales has been greatly limited by the low germination rates.Thereis thus a pressing need to develop an organogenesis protocol for in vitro propagation of T.amurensis to alleviate ashortage of high-quality T.amurensis seedlings.Here,we established a rapid in vitro propagation system forT.amurensis from mature zygotic embryos and analyzed the effects of plant growth regulators and culture mediain different stages.We found that Woody plant medium(WPM)was the optimal primary culture medium formature zygotic embryos.The highest callus induction percentage(68.76%)and number of axillary buds induced(3.2)were obtained in WPM+0.89μmol/L 6-benzyladenine(6-BA)+0.46μmol/L kinetin(KT)+0.25μmol/Lindole-3-butryic acid(IBA)+1.44μmol/L gibberellin A_(3)(GA_(3)).The multiple shoot bud development achievedthe highest percentage(83.32%)in the Murashige and Skoog(MS)+2.22μmol/L 6-BA+0.25μmol/L IBA+1.44μmol/L GA_(3).The rooting percentage(96.70%)was highest in 1/2 MS medium+1.48μmol/L IBA.Thesurvival percentage of transplanting plantlets was 82.22%in soil:vermiculite:perlite(5:3:1).Our study is the firstto establish an effective organogenesis protocol for T.amurensis using mature zygotic embryos.展开更多
Ejaculated mammalian spermatozoa contain a complex yet specific population of mRNA. However, the possible roles that mRNA has in early zygotic and embryonic development remain unclear. We found that Dby mRNA is select...Ejaculated mammalian spermatozoa contain a complex yet specific population of mRNA. However, the possible roles that mRNA has in early zygotic and embryonic development remain unclear. We found that Dby mRNA is selectively retained in capacitated mouse spermatozoa, and is transferred into the oocyte during fertilization by reverse transcription-polymerase chain reaction even though no DBY protein expression is detected. The cellular location ofDby mRNA is seen in the post-acrosome region, and it comprises nearly half of the mouse spermatozoa in in situ hybridization. In contrast, transcripts of the control gene, Smcy, are not detected in capacitated mouse spermatozoa, although the H-Y antigen encoded by Smcy is expressed on the surface of the spermatozoa. In our microinjection experiment, the zygotic development rate of the as-Dby male pronucleus injection group was significantly lower than that of the as-Smcy male pronucleus injection group （35.9% vs. 95%, P = 0.001） and the as-Dby female pronucleus injection group （35.9% vs. 93.8%, P = 0.001）. The rate of male-developed zygotes was also lower than that of the as-Smcy male pronucleus injection group （17.4% vs. 57.9%, P = 0.002） and the as-Dby female pronucleus injection group （17.4% vs. 54.1%, P = 0.002）. Thus, we conclude that Dby mRNA is selectively retained in capaci- tated mouse spermatozoa, and it has an important role in the early zygotic development of male mouse zygotes. This might imply that spermatozoa mRNA is involved in early zygotic and embryonic stages of reproduction.展开更多
Polyploid breeding is widely used in various marine species. Low salinity treatment is an effective method of inducing triploid of bivalve mollusks. In this study, RNA-seq was performed to determine genes and pathways...Polyploid breeding is widely used in various marine species. Low salinity treatment is an effective method of inducing triploid of bivalve mollusks. In this study, RNA-seq was performed to determine genes and pathways involved in hyposaline adaption and cell division of Pacific oyster(Crassostrea gigas) zygotes, trying to better understand the possible molecular mechanism of hypo-osmotic induction. A total of 26965 unigenes were generated in the de novo assembly of clean Illumina reads with an average length of 934 bp and N50 of 1721 bp. Of 3024 differentially expressed genes(DEGs), 2501 were up-regulated and 523 were downregulated. GO(Gene Ontology) annotation and KEGG(Kyoto Encyclopedia of Genes and Genomes) pathway analysis of these DEGs revealed that these DEGs participate a variety of biological processes including osmoregulation, cytoskeleton organization, cell survival and death, and substantially modulate cell proliferation and embryonic development. In summery, RNA-seq methodology was applied for the first time to demonstrate hypotonic-induced transcriptomic alteration in oyster zygotes. Our findings not only interpreted the relatively high mortality of induced larvae, but also provided a valuable reference for further investigations on the mechanism of hyposaline induction, thus should aid to the application of low salinity in triploid induction in large scale aquaculture in future.展开更多
目的:探讨二次超排方案对提高成年小鼠超排效果和胚胎发育潜能的可行性。方法:首先比较常规双排卵方案与自然排卵、随机超排实验方案所获总卵数的差异,然后在初步研究外源孕马血清促性腺激素(pregnant mare serum gonadotropin,PMSG)对...目的:探讨二次超排方案对提高成年小鼠超排效果和胚胎发育潜能的可行性。方法:首先比较常规双排卵方案与自然排卵、随机超排实验方案所获总卵数的差异,然后在初步研究外源孕马血清促性腺激素(pregnant mare serum gonadotropin,PMSG)对自然受孕一次胚胎发育影响的基础上,进一步对常规双排卵实验方案进行优化。结果:优化后的双排卵实验组单只鼠平均总卵数高达61.7枚,与自然排卵组、随机超排组和常规双排卵组差异显著,提升了成年小鼠的超排卵效果。结论:优化后的超数双排卵方案为同步大量获得小鼠多细胞胚胎及受精卵提供了一种新的、高效的技术方法。展开更多
Immature zygotic embryos of Quercus variabilis were as explants to induce somatic embryogenesis. Several factors influencing somatic embryogenesis have been assayed. Somatic embryos can be induced in MS and WPM basal ...Immature zygotic embryos of Quercus variabilis were as explants to induce somatic embryogenesis. Several factors influencing somatic embryogenesis have been assayed. Somatic embryos can be induced in MS and WPM basal medium, but there was more quantity, big size and high induction rate in MS medium. Induction rate was not significant cultured in light and dark condition. Zygotic embryos, collected in middle of July, gave higher rate of somatic embryogenesis than those collected on the earlier or later date. By adding 6-BA in medium individually, somatic embryogenesis appeared directly on the zygotic embryos without detectable callus. Secondary embryogenesis appeared in medium with 2,4-D individual or combined with 6-BA or TDZ. High induction frequency of 90% was achieved in MS medium supplemented with 0.5 mg·L -1 6-BA and 2,4-D, whereas the rate in hormone-free medium was only 16.7%. The genotypes of mother trees had an great impact on the inducing rate. Zygotic embryo surgery treatments were not favorable to embryogenesis. It was best to inoculate with entire zygotic embryos. The hypocotyl was a crucial part on somatic embryogenesis for Q. variabilis.展开更多
Maturing seeds were collected from fifty-year-old trees of Fraxinus mandshurica. The cotyledon and hypocotyl zygotic embryos were excised and cultured on 1/2MS media to induce somatic embryos. In cytological study of ...Maturing seeds were collected from fifty-year-old trees of Fraxinus mandshurica. The cotyledon and hypocotyl zygotic embryos were excised and cultured on 1/2MS media to induce somatic embryos. In cytological study of embryo development, by the way of paraffin, somatic and zygotic embryogenesis was observed and compared under light microscope. The results showed that somatic embryos from zygotic cotyledons originated directly from single epidermis cell. The somatic embryos that indirectly occurred on the embryogenic callus came from its singular surface cell or internal multi_cells. There was an obvious cytological difference between embryogenic and non-embryogenic callus. Somatic and zygotic embryogenesis underwent the similar course, passing through proembryo, heart, torpedo and cotyledonary stages. The important differences in morphogenetic process exited as following: volume of somatic embryos was smaller than its partner at the same development stage; somatic embryos had no obvious suspensors; somatic embryos showed morphologic variations.展开更多
基金This work was supported by the Science and Technology Development Plan Project of Jilin Province,China(20200402115NC).
文摘Tilia amurensis is an economically valuable broadleaf tree species in Northeast China.The production of highqualityT.amurensis varieties at commercial scales has been greatly limited by the low germination rates.Thereis thus a pressing need to develop an organogenesis protocol for in vitro propagation of T.amurensis to alleviate ashortage of high-quality T.amurensis seedlings.Here,we established a rapid in vitro propagation system forT.amurensis from mature zygotic embryos and analyzed the effects of plant growth regulators and culture mediain different stages.We found that Woody plant medium(WPM)was the optimal primary culture medium formature zygotic embryos.The highest callus induction percentage(68.76%)and number of axillary buds induced(3.2)were obtained in WPM+0.89μmol/L 6-benzyladenine(6-BA)+0.46μmol/L kinetin(KT)+0.25μmol/Lindole-3-butryic acid(IBA)+1.44μmol/L gibberellin A_(3)(GA_(3)).The multiple shoot bud development achievedthe highest percentage(83.32%)in the Murashige and Skoog(MS)+2.22μmol/L 6-BA+0.25μmol/L IBA+1.44μmol/L GA_(3).The rooting percentage(96.70%)was highest in 1/2 MS medium+1.48μmol/L IBA.Thesurvival percentage of transplanting plantlets was 82.22%in soil:vermiculite:perlite(5:3:1).Our study is the firstto establish an effective organogenesis protocol for T.amurensis using mature zygotic embryos.
基金This work is supported by the Agricultural Key Foundation of Shanghai, China （No. 2006-5-6）, the National Natural Science Foundation of China （No. 3091490）, the National Basic Research Program, China （No. 2009CB941704）, PhD Programs Foundation of Ministry of Education of China （No. 200802480026） and the Shanghai Leading Academic Discipline Project, China （No. B205）. We would like to extend our appreciation to Prof. Yi-Tao Zeng of the Shanghai Institute of Medical Genetics and Professor Lin He of the Bio-X Center of the Shanghai Jiao Tong University for their insightful comments.
文摘Ejaculated mammalian spermatozoa contain a complex yet specific population of mRNA. However, the possible roles that mRNA has in early zygotic and embryonic development remain unclear. We found that Dby mRNA is selectively retained in capacitated mouse spermatozoa, and is transferred into the oocyte during fertilization by reverse transcription-polymerase chain reaction even though no DBY protein expression is detected. The cellular location ofDby mRNA is seen in the post-acrosome region, and it comprises nearly half of the mouse spermatozoa in in situ hybridization. In contrast, transcripts of the control gene, Smcy, are not detected in capacitated mouse spermatozoa, although the H-Y antigen encoded by Smcy is expressed on the surface of the spermatozoa. In our microinjection experiment, the zygotic development rate of the as-Dby male pronucleus injection group was significantly lower than that of the as-Smcy male pronucleus injection group （35.9% vs. 95%, P = 0.001） and the as-Dby female pronucleus injection group （35.9% vs. 93.8%, P = 0.001）. The rate of male-developed zygotes was also lower than that of the as-Smcy male pronucleus injection group （17.4% vs. 57.9%, P = 0.002） and the as-Dby female pronucleus injection group （17.4% vs. 54.1%, P = 0.002）. Thus, we conclude that Dby mRNA is selectively retained in capaci- tated mouse spermatozoa, and it has an important role in the early zygotic development of male mouse zygotes. This might imply that spermatozoa mRNA is involved in early zygotic and embryonic stages of reproduction.
基金supported by the National Natural Science Foundation of China (No. 31172403)。
文摘Polyploid breeding is widely used in various marine species. Low salinity treatment is an effective method of inducing triploid of bivalve mollusks. In this study, RNA-seq was performed to determine genes and pathways involved in hyposaline adaption and cell division of Pacific oyster(Crassostrea gigas) zygotes, trying to better understand the possible molecular mechanism of hypo-osmotic induction. A total of 26965 unigenes were generated in the de novo assembly of clean Illumina reads with an average length of 934 bp and N50 of 1721 bp. Of 3024 differentially expressed genes(DEGs), 2501 were up-regulated and 523 were downregulated. GO(Gene Ontology) annotation and KEGG(Kyoto Encyclopedia of Genes and Genomes) pathway analysis of these DEGs revealed that these DEGs participate a variety of biological processes including osmoregulation, cytoskeleton organization, cell survival and death, and substantially modulate cell proliferation and embryonic development. In summery, RNA-seq methodology was applied for the first time to demonstrate hypotonic-induced transcriptomic alteration in oyster zygotes. Our findings not only interpreted the relatively high mortality of induced larvae, but also provided a valuable reference for further investigations on the mechanism of hyposaline induction, thus should aid to the application of low salinity in triploid induction in large scale aquaculture in future.
文摘目的:探讨二次超排方案对提高成年小鼠超排效果和胚胎发育潜能的可行性。方法:首先比较常规双排卵方案与自然排卵、随机超排实验方案所获总卵数的差异,然后在初步研究外源孕马血清促性腺激素(pregnant mare serum gonadotropin,PMSG)对自然受孕一次胚胎发育影响的基础上,进一步对常规双排卵实验方案进行优化。结果:优化后的双排卵实验组单只鼠平均总卵数高达61.7枚,与自然排卵组、随机超排组和常规双排卵组差异显著,提升了成年小鼠的超排卵效果。结论:优化后的超数双排卵方案为同步大量获得小鼠多细胞胚胎及受精卵提供了一种新的、高效的技术方法。
文摘Immature zygotic embryos of Quercus variabilis were as explants to induce somatic embryogenesis. Several factors influencing somatic embryogenesis have been assayed. Somatic embryos can be induced in MS and WPM basal medium, but there was more quantity, big size and high induction rate in MS medium. Induction rate was not significant cultured in light and dark condition. Zygotic embryos, collected in middle of July, gave higher rate of somatic embryogenesis than those collected on the earlier or later date. By adding 6-BA in medium individually, somatic embryogenesis appeared directly on the zygotic embryos without detectable callus. Secondary embryogenesis appeared in medium with 2,4-D individual or combined with 6-BA or TDZ. High induction frequency of 90% was achieved in MS medium supplemented with 0.5 mg·L -1 6-BA and 2,4-D, whereas the rate in hormone-free medium was only 16.7%. The genotypes of mother trees had an great impact on the inducing rate. Zygotic embryo surgery treatments were not favorable to embryogenesis. It was best to inoculate with entire zygotic embryos. The hypocotyl was a crucial part on somatic embryogenesis for Q. variabilis.
文摘Maturing seeds were collected from fifty-year-old trees of Fraxinus mandshurica. The cotyledon and hypocotyl zygotic embryos were excised and cultured on 1/2MS media to induce somatic embryos. In cytological study of embryo development, by the way of paraffin, somatic and zygotic embryogenesis was observed and compared under light microscope. The results showed that somatic embryos from zygotic cotyledons originated directly from single epidermis cell. The somatic embryos that indirectly occurred on the embryogenic callus came from its singular surface cell or internal multi_cells. There was an obvious cytological difference between embryogenic and non-embryogenic callus. Somatic and zygotic embryogenesis underwent the similar course, passing through proembryo, heart, torpedo and cotyledonary stages. The important differences in morphogenetic process exited as following: volume of somatic embryos was smaller than its partner at the same development stage; somatic embryos had no obvious suspensors; somatic embryos showed morphologic variations.
