CRISPR/Cas技术在抗除草剂作物育种中的研究与应用进展

CRISPR/Cas系统是一种简单、低成本、高效、精准的基因编辑技术,该技术能够进行基因的定向改造,加速新品种培育进程,在种质资源创制中的应用潜力较高。概述了CRISPR/Cas系统的技术原理及其在作物抗除草剂育种中的应用,简要指出了目前CRISPR/Cas技术在抗除草剂种质创制及应用过程中存在的问题及发展方向,以期为今后利用CRISPR/Cas技术创制抗除草剂新种质提供理论依据。     

Isolation and characterization of polymorphic microsatellites from Asian green mussel (Perna viridis)

Asian green mussels (Perna viridis) belonging to the family Mytilidae are native to the coastal and tropical marine waters of the Indo‐Pacific region. Ten polymorphic microsatellites were isolated and their polymorphisms were determined in 36 individuals. The average allele number of the 10 microsatellites was 11.7/locus with a range of two to 24 and the expected heterozygosity averaged at 0.69, ranging from 0.18 to 0.94. Eight out of 10 microsatellites agreed with the Hardy–Weinberg equilibrium and showed independent segregation. These microsatellites will facilitate the studying of the genetic diversity and population structure of the green mussel in and outside of the Indo‐Pacific region of Asia.     

Characterization of polymorphic tetranucleotide microsatellite loci from the Siberian weasel (Mustela sibirica)

Nine tetrarepeat microsatellite loci for Siberian weasel (Mustela sibirica) were characterized. By using 35 individuals of unknown relationship collected from Taiwan, we evaluated the polymorphism of these loci. The number of alleles for each locus ranged from five to 12 (mean = 8.78 alleles) and the observed heterozygosity from 0.429 to 0.962 (mean = 0.688) and all loci conformed to Hardy–Weinberg expectation.     

Isolation and characterization of polymorphic microsatellite loci in Hemibarbus labeo (Cyprinidae) using PCR‐based isolation of microsatellite arrays (PIMA)

A total of 10 polymorphic microsatellite loci from Hemibarbus labeo were isolated and characterized using an optimized protocol to construct a microsatellite‐enriched genomic library. The analysis of variability was performed in 24 specimens of mainland China. The mean number of alleles across loci was 3.10 ± 1.10 and the level of expected heterozygosity varied from 0.0417 to 0.7482. Frequencies of null alleles of the 10 loci are not significantly greater than zero. No linkage disequilibrium was detected between loci in either population. Five primer pairs cross‐amplify the microsatellites in other species, indicating transportability of the markers within the family Cyprinidae.     

Characterization and the broad cross‐species applicability of 20 anonymous nuclear loci isolated from the Taiwan Hwamei (Garrulax taewanus)

We isolated 20 anonymous nuclear loci (8556 bp in total) from the Taiwan Hwamei (Garrulax taewanus), an endemic songbird of Taiwan. A panel of nine to 15 individuals with unknown relationship was used to characterize polymorphism of these loci. We identified 46 single nucleotide polymorphic sites (SNPs) in 15 polymorphic loci. Frequency of SNPs was one per every 186 bp in average. Nucleotide diversity, θ, ranged from 0.00054 to 0.00371 per locus. We also tested cross‐species applicability of these loci on 17 species from eight different passerine families. All 20 loci could be successfully amplified (ranged from one to 16 species, mean = 7.9 species).     

中国荨麻科植物省级分布新记录

报道荨麻科6种1亚种1变种在我国6个省区分布的新记录,其中山东分布新记录的有海岛苎麻 (Boehmeria formosana),陕西分布新记录的有对叶楼梯草(Elatostema sinense),广东分布新记录的有台湾糯米团(Gonostegia parvifolia),贵州分布新记录的有显脉楼梯草(Elatostema longistipulum)和短毛楼梯草(E. nasutum var. puberulum),云南分布新记录的有高原荨麻(Urtica hyperborea),西藏分布新记录的有单蕊麻 (Droguetia iners subsp. urticoides)和细尾楼梯草(Elatostema tenuicaudatum)。     

小儿表浅静脉采集血标本成功率影响因素

目的：研究小儿表浅静脉采集血标本成功率影响因素,探讨提高表浅静脉采集血标本成功率的有效护理对策。方法：对每种影响因素进行分组研究,每组按随机分组原则设试验组和对照组,采取所需血量为成功,未采取所需血量为不成功。结果：常见几种影响因素试验组与对照组差异有统计学意义（p〈0.01）。结论：小儿表浅静脉采集血标本影响因素是多方面的,采血前必须对患儿进行综合评估,选择恰当的采血方法。     

(2R,3S,4S)-2-(N,N-二乙氨基)甲酰氧基-3-苯基-4-苯甲酰基-N-甲基-γ-内酰胺的合成及工艺研究

目的：通过对黄皮酰胺全合成中间体（2R,3S,4S）-2-羟基-3-苯基-4-苯甲酰基-N-甲基-γ-内酰胺（化合物A）2位羟基的酯化,提高脂水分配系数（kP）,考察对谷丙转氨酶活性的影响。方法：以化合物A为原料,通过酰化反应合成（2R,3S,4S）-2-（N,N-二乙氨基）甲酰氧基-3-苯基-4-苯甲酰基-N-甲基-γ-内酰胺（化合物B）,重点考察了摩尔比、反应温度、反应时间等条件对反应的影响。化合物B结构已经元素分析、红外光谱、质谱及核磁共振氢谱确证。结果：化合物A和酰化剂以摩尔比2：3,在160℃下反应1h,目标化合物B。收率78．42％。结论：本合成路线及具体反应方法,具有试剂廉价易得、反应条件温和、后处理简便等优点,是一种较为实用的合成方法。     

实验性动脉粥样硬化家兔MIF、TNF-α和IL-6水平的研究

目的:对实验性动脉粥样硬化家兔血清中巨噬细胞移动抑制因子、肿瘤坏死因子、白介素-6含量进行分析,以探讨它们在冠心病发病过程中的意义。方法:研究对象为新西兰大白兔,随机分成对照组(10只)和实验组(10只)。对照组喂食基础饲料,实验组喂食高脂饲料(基础饲料中加入1%胆固醇 5%猪油)。均喂饲8周后采用ELISA法检测其血清MIF、TNF-α、IL-6水平。结果:组织病理切片结果显示实验组兔主动脉弓内膜增厚,动脉粥样斑块明显。与对照组比较,实验组MIF、TNF-α、IL-6水平均升高,其差别有显著性(p＜0．01)。结论:MIF、TNF-α、IL-6与动脉粥样硬化的发生有密切关系,这些细胞因子可通过相互诱导、相互协同共同参与冠心病的发生、发展过程。     

CHO细胞基因组中稳定hot spot位点研究进展

近些年来,治疗性重组蛋白类药物是生物制药领域研究的热点。工业化生产中常用于重组蛋白表达的细胞系是中国仓鼠卵巢(Chinese hamster ovary,CHO)细胞。传统CHO细胞系的表达大多数基于随机整合的方式,这可能会使目标基因整合到异染色质区域或者不稳定的染色质区域,导致CHO细胞表达不稳定,需要多轮筛选才能获得理想的表达细胞系。最新研究表明,外源基因在CHO细胞预测/特定的基因组位点中进行特异性整合,可以使重组CHO细胞的表达保持长期一致性和稳定性。CHO细胞基因组中高效稳定的转录整合位点被称为热点(hot spot)。阐述CHO细胞基因组稳定的hot spot位点近几年的研究进展,其中包括热门的hot spot位点,以及如何研究新的hot spot位点的方法。总结如何将外源基因高效定位于预测的CHO细胞hot spot位点,实现高水平稳定的表达重组蛋白,为发现新的有效的hot spot位点,构建稳定表达CHO细胞系提供参考。