The Breeding of Mutant p53 and Neu/erb B2 Dual transgenic Mice: Both of the Genes were Over expressed Specifically in the Mammary Gland

为了研究乳腺癌发生与发展过程中突变型ｐ５３和Ｎｅｕ基因之间的相互作用,我们构建了ｐ５３／Ｎｅｕ双转基因鼠。用５只成年雄性Ｎｅｕ转基因鼠与１０只成年雌性ｐ５３转基因鼠交配,对１５０只雌性杂交后代鼠进行ｐ５３／Ｎｅｕ双转基因鼠的筛选。为此,本实验建立了ＰＣＲ一步鉴定法。即：在同一个反应管内能同时满足小鼠β酪蛋白基因、ｐ５３基因和Ｎｅｕ基因上三个片段（分别为０．５ｋｂ、１．２ｋｂ、１．７ｋｂ）的扩增反应者被断定为双转基因鼠（Ｆｉｇ．１）。传统的Ｓｏｕｔｈｅｒｎ分析（Ｆｉｇ．２）与ＰＣＲ一步法鉴定结果相吻合。证明：该法的准确率为１００％。进一步、随机取样,Ｎｏｒｔｈｅｒｎ分析（Ｆｉｇ．３）表明：双转基因鼠（２号）在哺乳笫二天即出现了ｐ５３基因的高表达。继而、在姓娠笫１０、１７天,哺乳笫１０、２１天也检测到该基因的表达。另外,免疫组化染色也检测到了ｐ５３和Ｎｅｕ蛋白（未展示结果）。     

CRISPR/Cas9 screening using unique molecular identifiers

Loss‐of‐function screening by CRISPR/Cas9 gene knockout with pooled, lentiviral guide libraries is a widely applicable method for systematic identification of genes contributing to diverse cellular phenotypes. Here, Random Sequence Labels (RSLs) are incorporated into the guide library, which act as unique molecular identifiers (UMIs) to allow massively parallel lineage tracing and lineage dropout screening. RSLs greatly improve the reproducibility of results by increasing both the precision and the accuracy of screens. They reduce the number of cells needed to reach a set statistical power, or allow a more robust screen using the same number of cells.     

长白山地区蚱属一新种(直翅目,蚱总科)

报道采自长白山地区蚱属昆虫一新种,长白山蚱Tetrix changbaishanensis sp．nov．。模式标本保存在东北师范大学生命科学学院动物标本室。     

Cryopreservation of sperm from Atlantic halibut (Hippoglossus hippoglossus, L.) for commercial application

Development of Atlantic halibut (Hippoglossus hippoglossus) aquaculture will be enhanced with cryopreservation of halibut sperm by ensuring a reliable supply of sperm of desired quality and quantity. To assist in its commercial application, the cryopreservation of large volumes of halibut sperm was investigated. Three cryoprotectants were compared: dimethyl sulfoxide (DMSO), polyethylene glycol (PG) and glycerol (GLY) at two concentrations (10% or 15%). Two salt solutions, Hanks’ balanced salt solution (HBSS) and 0.1 M KHCO₃ with 0.125 M sucrose solution (KS) were tested as diluents. Both factors were examined in 1.6 mL volumes. A cryopreservation volume of 4 mL and a low dilution ratio (1:1) were examined separately. Based on motility and fertilization rate, 10% and 15% DMSO diluted with HBSS or KS solution proved to be effective extenders with mean fertilization rates ranging from 52.2 ± 27.2% to 65.8 ± 26.1%; none of which were significantly different from that of the control. Four other extenders, 10% PG or 10% GLY with HBSS or KS, resulted in significantly lower fertilization rates. Use of a 4 mL cryopreservation volume did not exhibit a significant effect on fertilization rate or motility of post-thawed sperm compared to a 1.6 mL volume (P > 0.05); while the use of a dilution ratio of one part sperm with three parts cryopreservation solution (1:3 v/v with sperm concentration of 0.51 ± 0.11 × 10¹⁰ cells/ml) had a significantly better preservation effect than using a ratio of 1:1 with sperm concentration of 1.02 ± 0.21 × 10¹⁰ cells/ml (P < 0.05). From these results, an optimized protocol for the cryopreservation of Atlantic halibut sperm using a volume as large as 4 mL has been established.     

Identification of EGF as an Important Regulator for Promoting CYP3A4 Expression in Human Embryonic Stem Cell-Derived Hepatocytes Using TALEN-Based Gene Targeting

Functional human hepatocytes are one of the most significant tools for studying drug absorption, distribution, metabolism and excretion/toxicity （ADME/Tox）, especially for applications in preclinical drug development （Sahi et al., 2010; Godoy et al., 2013）. They provide the closest in vitro model to the human liver and the only model that mimics the drug metabolic profiles found in vivo. However, these cells lose their metabolic function rapidly and dramatically during the in vitro culture process, which largely hinders their wider application in drug development （Sahi et al., 2010; Godoy et al., 2013）. To overcome this obstacle, it is important to regulate the activities of key genes which are responsible for the detoxification metabolic function of human hepatocytes.     

赖氨酸特异性组蛋白去甲基化酶1与白血病的研究进展

表观遗传学是后基因组时代兴起的一门新学科,它使人们认识到包括DNA甲基化、组蛋白修饰、染色质重塑及非编码RNA调控在内的修饰也可以记载遗传信息;并且许多表观遗传改变是可逆的,对表观遗传修饰和调控的研究已成为生命科学的热点和发展前沿。2004年发现的赖氨酸特异性组蛋白去甲基化酶1(LSD1)是第一个真正意义上的组蛋白赖氨酸去甲基化酶,使人们认识到组蛋白甲基化是一个动态的过程,通过组蛋白甲基转移酶和去甲基化酶的相互作用,动态地调控基因转录的激活和抑制等生物学过程。这重新定义了组蛋白甲基化,同时也为进一步深入研究组蛋白修饰提供了新的途径。我们在此简要介绍LSD1的结构与功能、LSD1与白血病的关系,LSD1在白血病的发生和发展中发挥重要作用,是一个潜在的治疗白血病的靶基因。     

植物耐盐相关基因：SOS基因家族研究进展

土壤盐渍化是影响农业生产和生态环境的一个非常重要的非生物胁迫因素,也是现代生物科学迫切需要解决的问题。利用拟南芥研究植物耐盐相关基因成为该领域的研究热点。几年来,该领域研究成果斐然。本文就SOS基因家族的三个耐盐基因SOS1、SOS2和SOS3的克隆、功能及相互关系作一概要的评述。 Abstract:The soil salination is a significant abiotic stress for agricultural production and ecological environment. The research on salt tolerance represents an important part for basic plant biology. Genetic analysis of salt tolerance genes in Arabidopsis has become a central issue in this research areas. In recent years, efforts from some laboratories in the world have led to some significant progresses in this field. In this paper, we will review the progress in salt tolerance genes SOS(salt overly sensitive):SOS1,SOS2 and SOS3.     

灌浆期喷施6-BA对甜玉米一些生理指标的影响

甜玉米灌浆期喷施不同浓度6-BA后,叶片叶绿素含量、光合速率、比叶重均提高,丙二醛含量和外渗电导率明显降低,籽粒中可溶性糖和维生素C含量均提高.     

Lipidomic changes during different growth stages of Nitzschia closterium f. minutissima

Ultra Performance Liquid Chromatography-Electrospray ionization-Quadrupole-Time of Flight Mass Spectrometry (UPLC-ESI-Q-TOF–MS) is a powerful lipidomic tool. In this study, we developed a UPLC/Q-TOF–MS based method to investigate the lipid metabolomic changes in different growth phases of Nitzschia closterium f. minutissima. The data classification and biomarker selection were carried out by using multivariate statistical analysis, including principal components analysis (PCA), projection to latent structures with discriminant analysis (PLS-DA), and orthogonal projection to latent structures with discriminant analysis (OPLS-DA). We discovered that the intercellular lipid metabolites were significantly different among exponential, early stationary and late stationary phases. Thirty-one lipid molecules were selected and identified as putative biomarkers, including free fatty acid, Harderoporphyrin, phosphatidylglycerol, 1,2-diacyglycerl-3-O-4′-(N,N-trimethy)-homoserine, triacylglycerol, cholesterol, sulfoquinovosyldiacylglycerol, lyso-sulfoquinovosyldiacylglycerol, monogalactosyldiacylglycerol, digalactosyldiacylglycerol and lyso-digalactosyldiacylglycerol. These lipids have been shown previously to function in energy storage, membrane stability and photosynthesis efficiency during the growth of diatoms. Further analysis on the putative biomarkers demonstrated that nitrate starvation played critical role in the transition from exponential phase to stationary phase in N. closterium. This study is the first one to explore the lipidomic changes of microalgae in different growth phases, which promotes better understanding of their physiology and ecology.