4种栽培大麦染色体组型和C-带带型的比较分析

对栽培大麦4个品种的染色体组型和C-分带带型进行了分析和研究,结果表明:不同大麦品种的染色体C带的分布在数目和强弱存在明显差异,不同大麦品种同一序号的染色体表现不同程度的C-带带型的多态性.     

Development of a pyrF-based counterselectable system for targeted gene deletion in Streptomyces rimosus

Streptomyces produces many valuable and important biomolecules with clinical and pharmaceutical applications. The development of simple and highly efficient gene editing tools for genetic modification of Streptomyces is highly desirable. In this study, we developed a screening system for targeted gene knockout using a uracil auxotrophic host(Δpyr F) resistant to the highly toxic uracil analog of 5-fluoroorotic acid(5-FOA) converted by Pyr F, and a non-replicative vector p KC1132-pyr F carrying the complemented pyr F gene coding for orotidine-5'-phosphate decarboxylase. The pyr F gene acts as a positive selection and counterselection marker for recombinants during genetic modifications. Single-crossover homologous integration mutants were selected on minimal medium without uracil by reintroducing pyr F along with p KC1132-pyr F into the genome of the mutant Δpyr F at the targeted locus. Double-crossover recombinants were generated, from which the pyr F gene, plasmid backbone, and targeted gene were excised through homologous recombination exchange. These recombinants were rapidly screened by the counterselection agent, 5-FOA. We demonstrated the feasibility and advantage of using this pyr F-based screening system through deleting the otc R gene, which encodes the cluster-situated regulator that directly activates oxytetracycline biosynthesis in Streptomyces rimosus M4018. This system provides a new genetic tool for investigating the genetic characteristics of Streptomyces species.     

番茄ACC合成酶反义基因在转基因猕猴桃中表达的初步研究

利用从番茄(Lycopersicum esculentumMill.)果实中分离到的ACC合成酶cDNA基因，反向置于CaMV35S启动子的控制之下(所用根癌杆农菌中合有改建后分别携带嵌合NPT Ⅱ基因和番茄的ACC合成酶反义基因的质粒)，并转入美味猕猴桃(Actinidiadeliciosa cv.Hayward)的愈伤组织中。通过分化，2周后获得了能在附加羧苄青霉素(Carbenicillin,500mg/l)和卡那霉素(Kanamycin,50mg/l)的MSA(MS盐类，3．0mg/lBA，0．2mg/l IAA)培养基上生长的抗性愈伤组织。经过半年多的继代培养并筛选，获得了大量的抗卡那霉素(50mg/l)的丛芽以及由抗性芽发育形成的抗性试管苗。探讨了在用卡那霉素进行筛选的条件下影响愈伤组织诱导率的一些因素。     

Investigation of the biological roles of autophagy in appressorium morphogenesis in Magnaporthe oryzae

Magnaporthe oryzae has been used as a primary model organism for investigating fungus-plant interaction. Many researches focused on molecular mechanisms of appressorium formation to restrain this fungal pathogen. Autophagy is a very high conserved process in eukaryotic cells. Recently, autophagy has been considered as a key process in development and differentiation in M. oryzae. In this report, we present and discuss the current state of our knowledge on gene expression in appressorium formation and the progress in autophagy of rice blast fungi. Project supported by the National Natural Science Foundation of China (Nos. 30671351 and 30870101) and the Hi-Tech Research and Development Program (863) of China (No. 2002AA245041)     

ACE基因多态性与有氧耐力的研究现状

随着人类基因组计划的完成,后基因组计划的全面展开,以基因工程为主导的生物技术在体育运动问题领域的应用得到广泛关注.目前,人们普遍认为ACE(血管紧张素转化酶)水平和心血管的形态、功能密切相关.ACE基因的多态性是人耐力素质优劣的决定性因素之一,其作为一个有价值的遗传标志,有望成为科学选材的理想指标.     

线粒体基因突变糖尿病的临床研究进展

线粒体基因突变糖尿病的发现是近年来糖尿病分子遗传学研究的重要进展之一,也是近年来糖尿病研究的一大热点。线粒体tRNA^leu（uuR）A3243G突变导致胰岛B细胞功能缺陷,进而导致线粒体糖尿病的发生。WHO已将此型糖尿病归类为特殊类型糖尿病。综述此型糖尿病的临床表现及其分子诊断学方法和临床研究进展。     

"物种混合"引起的伦理困境及其解决思路

用于治疗各种严重威胁人类疾病的基因移植和干细胞技术已经使制造越来越多的人兽混合体变得更容易和更迫切,当代社会出现了许许多多人兽混合的"喀迈拉"."喀迈拉"对人类伦理的挑战主要表现在:人体干细胞的来源、这些人兽混合体的生物学地位、社会地位和繁育后代等问题上都与人类的道德认同存在巨大反差.在对待"物种混合"引起的道德禁忌问题上,人类的态度应该更宽容一些.     

CNTF基因A/G多态性与我国优秀单板U型场地运动员运动能力的相关性分析

为探求CNTF（睫状神经营养因子）基因的A/G多态位点与我国优秀单板U型场地运动员运动能力（尤其是力量素质）的相关性.文章选择20名优秀单板U型场地运动员和115名普通无专业训练的大学生作为研究对象,采用PCR-RFLP实验法测试CNTF基因的A/G多态位点,并用基因平衡定律测试结果,用基因平衡定律（H-W）检验,组间基因型与等位基因分布采用卡方检验方法.结果显示：对照组等位基因频率为A =18.7％,G=81.3％,基因型频率为A/A =6.1％,A/G=25.2％,G/G=68.7％;实验组等位基因频率为A =17.5％,G=82.5％,基因型频为A/A=10％,A/G=15％,G/G=75％.说明CNTF三种基因型分布频率的趋势为GG型＞AG型＞AA型,等位基因无差异（P＞0.05）.提示CNTF基因A/多态性不能作为中国技能主导类优秀滑雪运动员选材的指标之一,但GG基因型所占比例大.     

运动基因组学的研究进展

目的:回顾目前在理解运动员能力遗传决定论方面的进展,并描述一些新的、重要的、可能成为精英运动员的差异标记的基础的DNA多态性。方法:通过文献综述和归纳分析法对过去几十年运动基因组学的研究进展作了简单的回顾。结果:运用全基因组关联研究(GWAS),在过去几年确定了41种标志物,这表明GWASs是一种有前景、富有成效的研究运动相关表型的方法。结论:未来的研究,包括多中心GWAS和大群运动员的全基因组测序的验证和复制研究,将有助于发现大量能部分解释运动能力和相关表型的遗传力的遗传变异(突变和DNA多态性)。