一种快速、高效花生植株再生体系的建立

快速、高效、重复性好的植株再生体系是转基因育种的基础;本研究以14份不同花生品种的胚小叶为外植体,利用不同激素浓度、组合和不同花生基因型筛选最佳芽诱导培养基、伸长培养基和高效再生基因型。结果表明最佳丛生芽诱导培养基为MSB;＋0．2mg·L-1NAA＋6mg·L-1 6-BA,诱导率为89．50％;最佳伸长培养基为MSB5＋0．2mg.L-1 NAA＋3mg’L-1 6-BA和MSB;＋O．2mg·L～NAA＋4mg·L-1 6-BA＋2mg·L～GA,交替培养,每个丛生芽伸长数达到7．24,时间缩短至3-4周。不同品种再生率的变幅在25．51％～93．01％,大于80％的品种有‘麻油1-1’、‘弗落蔓生’、‘濮花23号’、‘海花1号’。利用‘弗落蔓生’在15周内得到了生根组培苗。     

一种快速提取组织外泌体的分离富集方法

本文提供一种快速提取组织外泌体的分离富集方法。通过将目标组织用机械法切碎,加入组织消化酶进行组织解离和过滤,将获得的组织细胞悬液依次进行差速离心、超离、尺寸排阻和超滤,实现组织高质量外泌体的富集纯化。组织解离方法比较试验中,采用组织消化酶解离组织得到的蛋白质含量更高,获得的外泌体组织来源的蛋白质污染小。富集小鼠心组织、小鼠肝组织、小鼠肾组织、人结肠癌组织、人乳腺癌组织和动脉粥样硬化组织的外泌体,并对其进行纳米粒径追踪和透射电镜观察。结果显示,外泌体的粒径均在30~150 nm内,结构清晰明确。对小鼠肝组织富集的外泌体进行蛋白质印迹分析。结果显示,阳性蛋白质标志物CD9、ALIX和CD63的表达,TSG101弱表达,阴性蛋白质标志物Calnexin无表达。本方法集合多种分离措施,能够达到分离纯化外泌体的作用,同时简化了分离组织外泌体的步骤,相对于其他方法,全程只需要4~5 h,节省了富集时间,所富集的外泌体纯度高、可溶性杂蛋白质污染小,实用性更加广泛。使用微量组织样本富集的外泌体即可满足后续纳米粒径追踪、蛋白质印迹、透射电镜和转录物组等分析。     

一种有推广价值的快速全血PCR技术

一种有推广价值的快速全血ＰＣＲ技术张立冬张杰朱天慧（南开大学医学院,天津３０００７１）ＡＶａｌｕａｂｌｅＲａｐｉｄＰＣＲＭｅｔｈｏｄＵｓｉｎｇＷｈｏｌｅＢｌｏｏｄＺｈａｎｇＬｉｄｏｎｇＺｈａｎｇＪｉｅＺｈｕＴｉａｎｈｕｉ（ＭｅｄｉｃａｌＣｏｌｅｇｅｏ...     

从血液中提取总RNA的一种快速高效方法

血液中含有大量的RNA酶 ,可引起RNA的降解 .防止RNA酶的降解 ,是保证所得RNA片段完整的关键 .目前提取RNA的方法较多 ,但有些方法尚不能完全防止RNA降解 .将TRIZOL方法稍加改进 ,将TRIZOL与异硫氰酸胍联用提取血液淋巴细胞总RNA .琼脂糖凝胶电泳结果表明 ,其 2 8SRNA与 18SRNA的比值为 2∶1,优于单独使用其中任何一种试剂者 .此方法同样适用于从其它细胞中提取RNA .     

A Rapid Method for Sectioning Whole Mature Coniferous Seeds for Histological and Histochemical Study

A method is given for rapidly sectioning whole mature conifer seeds. The procedure consists of soaking seeds in water and allowing the seed contents to swell, whereupon the seeds are sectioned in a cryostat. Sections thus prepared are suitable for histological and histochemical staining.     

一种快速高效的水稻原生质体制备和转化方法的建立

在模式植物拟南芥中,原生质体瞬时表达技术已被广泛地应用到功能基因组学的研究中,但水稻原生质体因其制备过程相对繁琐,转化效率偏低,尚未在基因功能研究中获得广泛应用。本研究在拟南芥原生质体制备和转化的基础之上,对水稻原生质体的制备和转化方法进行改良优化。以水稻幼茎为起始材料,采用纤维素酶R-10和果胶酶R-10,对水稻组织进行消化并利用蔗糖密度梯度自沉降的方法分离原生质体,获得了高纯度的原生质体。对质粒转化原生质体时的转化方法、转化时间及质粒浓度进行探索,在缩短原生质体分离时间的同时,大大提高了转化效率。用较少量的质粒DNA即可获得外源基因在原生质体内高效的表达,且转化效率可达70％。我们建立的这种快速有效的水稻原生质体制备和转化方法,可为水稻功能基因组学研究提供技术支持。     

A Rapid Method for Whole Mount Preparations of Mammalian Oocytes and Early Embryos

Whole mounts of mouse oocytes and embryos are useful for observing intracellular structures while preserving morphological integrity. This method is inconvenient for rapid processing of a large number of specimens because washing each specimen in a protein-free solution is required prior to transfer into the fixative. We have developed a new fixative which does not cause protein precipitation which can be added directly to the culture medium. Specimens can be preserved in culture dishes for at least one month, and processed for cytological observation at a convenient time. When stained with hematoxylin, details of cellular structures such as nuclei, nucleoli, chromosomes and spindle microtubules can be observed while maintaining the organization of the organelles.     

A Rapid Method for Whole Mount Preparations of Mammalian Oocytes and Early Embryos

Whole mounts of mouse oocytes and embryos are useful for observing intracellular structures while preserving morphological integrity. This method is inconvenient for rapid processing of a large number of specimens because washing each specimen in a protein-free solution is required prior to transfer into the fixative. We have developed a new fixative which does not cause protein precipitation which can be added directly to the culture medium. Specimens can be preserved in culture dishes for at least one month, and processed for cytological observation at a convenient time. When stained with hematoxylin, details of cellular structures such as nuclei, nucleoli, chromosomes and spindle microtubules can be observed while maintaining the organization of the organelles.     

A Digital PCR-Based Method for Efficient and Highly Specific Screening of Genome Edited Cells

The rapid adoption of gene editing tools such as CRISPRs and TALENs for research and eventually therapeutics necessitates assays that can rapidly detect and quantitate the desired alterations. Currently, the most commonly used assay employs “mismatch nucleases” T7E1 or “Surveyor” that recognize and cleave heteroduplexed DNA amplicons containing mismatched base-pairs. However, this assay is prone to false positives due to cancer-associated mutations and/or SNPs and requires large amounts of starting material. Here we describe a powerful alternative wherein droplet digital PCR (ddPCR) can be used to decipher homozygous from heterozygous mutations with superior levels of both precision and sensitivity. We use this assay to detect knockout inducing alterations to stem cell associated proteins, NODAL and SFRP1, generated using either TALENs or an “all-in-one” CRISPR/Cas plasmid that we have modified for one-step cloning and blue/white screening of transformants. Moreover, we highlight how ddPCR can be used to assess the efficiency of varying TALEN-based strategies. Collectively, this work highlights how ddPCR-based screening can be paired with CRISPR and TALEN technologies to enable sensitive, specific, and streamlined approaches to gene editing and validation.