植物细胞核雄性不育的分子基础

植物细胞核雄性育性相关基因克隆,使我们对细胞核雄性育性的了解不仅局限于遗传分析和细胞学水平,而且对细胞核不育的分子基础,以及细胞核不育的分子机理也有了一定的了解。本文旨在对细胞核雄性不育相关研究的进展情况进行简要综述。Abstract:With the cloning of nuclear male fertility genes,learning of nuclear male fertility not only limited in genetic analysis and cell biology,but also advanced in molecular basis of male nuclear sterility and postulated in possible mechanisms of nuclear male sterility.The objectives of this paper are to review the related progress of plant nuclear male sterility.     

基因表达的转录后与翻译起始调控

基因表达的转录后与翻译起始调控彭晓冬,童坦君（北京医科大学生化与分子生物学系,北京１０００８３）关键词转录后调控,翻译起始调控,ＲＮＡ结构近年来,基因表达的转录调控研究十分深入。转录以后诸过程的调控机制研究亦越来越引人注目。一般认为,对ｍＲＮＡ成熟、...     

生物钟的转录后与翻译后水平调控进展

哺乳动物中的昼夜节律系统由位于下丘脑SCN核内的生物钟主钟和位于多数外周细胞中的子钟组成。在分子水平上,生物钟的节律振荡由生物钟基因及其编码蛋白的转录和翻译形成的自主的反馈环路组成,并接受外界因素的影响与环境周期保持同步。为此,就生物钟的调控机制而言,除了转录水平的基因表达调控外,生物钟转录产物和蛋白质的修饰也可以显著影响生物钟基因的表达时相。讨论了一些转录后与翻译后的修饰作用及其对生物钟的影响,并对其今后的研究方向作了展望。     

基于转录组与翻译组的海洋食烷菌(Alcanivorax)烷烃代谢调控研究

【目的】食烷菌是海洋烃类降解优势菌,其烷烃代谢调控机制有待深入研究。本研究拟从食烷菌转录和翻译水平上认识烷烃降解的调控过程。【方法】分别以乙酸和正十六烷(C16)为唯一碳源与能源,获取柴油食烷菌(Alcanivorax dieselolei) B5菌株的转录组和翻译组数据,并整合数据计算得到该菌在2种碳源培养条件下基因的翻译效率。采用基因本体论(gene ontology, GO)和京都基因和基因组百科全书(Kyoto encyclopedia of genes and genomes, KEGG)对差异翻译和翻译效率基因进行功能和代谢通路注释。【结果】当以C16为唯一碳源与能源时,B5菌株烷烃代谢途径的关键基因在转录与翻译水平均大量提升,包括烷烃单加氧酶、细胞色素P450氧化酶、醇脱氢酶和醛脱氢酶等。KEGG富集结果表明,翻译水平显著上调基因参与了肽聚糖生物合成、脂肪酸降解、氯代烷烃降解、氧化磷酸化和生物膜形成等通路;翻译效率差异基因主要富集在铁载体非核糖体肽的生物合成、氧化磷酸化和不饱和脂肪酸的生物合成等途径。通过转录组和翻译组学的联合分析显示,为了适应烷烃氧化,B5有效地协调了转...     

蛋用鹌鹑伴性羽色基因互作与连锁的关系

本研究首次发现了鹌鹑伴性羽基因的基因互作关系并进行了遗传验证.试验证明,鹌鹑的栗羽、黄羽和白羽是Z染色体上两个有连锁关系的基因座B/b和Y/y相互作用的结果.B和b为一对等位基因,不控制任何性状,只与色素的合成有关,B为有色基因,b为白化基因,B对b为显性;Y和y为另一对等位基因,分别控制栗羽和黄羽,Y对y为显性.栗羽和黄羽的表现取决于有色基因B的存在,B与Y相互作用产生栗羽,B与y相互作用产生黄羽,白羽是白化基因b对Y和y上位作用的结果.B/b和Y/y两基因座在雄性表现出一定的互换率,在雌性为完全连锁.这一研究补充和发展了以前人们对鹌鹑羽色伴性遗传的研究,为人们利用鹌鹑羽色进行自别雌雄配套系生产提供了重要的遗传学基础。Abstract:The interaction of sex-linked gene for plumage color in quails was first discovered and identified by genetictest.It was proved that the phenotypic expressions of the maroon feather,the yellow feather and the white feather result from the interaction between B/b and Y/y loci in the Z-chromosome.The allele B and b have something to do with the composition of pigment in plumage and nothing to do with any relative characters,the coloured gene B is dominant to its albino allele b.The maroon and yellow feather constituted a pair of relative characters determined by a couple of alleles Y and y,the maroon feather was caused by a dominant allele Y,and the yellow feather caused by a recessive allele y.But the phenotypic expression of maroon and yellow was decided by the present of the coloured gene B in Z-chromosome,the maroon feather was the result of interaction between gene B and Y,the yellow feather was result of interaction between gene B and y.The white was caused by a recessive albino gene b which epistasis to gene Y and y.The incomplete linkage was present between B/b and Y/y in Z-chromosome in male and complete linkage in female.This research enriches and delelops the earlier studies of the sex-linked inheritance of plumage color.It provides an important genetic basis for the quail autosexing system production by means of plumage color.     

大白菜及近缘作物核不育两用系的育性遗传多样性探讨

在大白菜及其近缘芸薹属作物中,根据仅表现可育和不育这类核不育材料遵循孟德尔规律的事实,提出了育性遗传多样性通式GMS=[(Mf>Ms>mf>ms)±a＋b]n（a=0,1,2;b=0,1,2;n=1,2,3）,并就此展开了讨论。Abstract：Based on the fact that within the heading Chinese cabbabe-pe-tsai and related crops,those genic sterile materials showing only fertility and sterility follow Mendel law,fertility hereditary diversity formula GMS=[(Mf>Ms>mf>ms)±a＋b]n（a=0,1,2 b=0,1,2 n=1,2,3） was presented and discussions were made.     

四部体小麦“简阳矮兰麦”与黑麦可杂交性及其在六倍体水平上的遗传特性

中国六倍体普通小麦地方品种有一个比较独特的特征-存在丰富的高亲和性材料。因此,研究中国四倍体小麦的亲和性问题具有特殊的意义。“简阳矮兰麦”是来源于四川省的一个四倍体小麦地方品种,它与黑麦有高的可杂交性,其杂交结实率达60%。遗传分析表明,“简阳矮兰麦”与黑麦的高可杂交性是受2-3对隐性基因所控制,但3对基因的可能性更大。而且,这些隐性基因的作用在合成六倍体小麦后仍能比较完全的表达。通过与六倍体普通小麦相比较,结果表明四倍体小麦的可杂交性系统与六倍体小麦的可杂交性系统的作用方式是类似的。Abstract:It is a special characteristic that many Chinese common wheat landraces showed a high crossability with rye.Thus,it is important that elucidate the genetic control of the crossability of Chinese tetraploid wheat with rye.Triticum turgidum cv.Jianyangailanmai native to Sichuan,China has high crossability with rye,up to 60%.In this study,it is indicated that the crossability of Jianyangailanmai with rve is controlled by two or more probably three recessive genes,which was almost totally expressed in the hexaploid wheat level.The operation of these recessive genes influencing crossability with rye was similar to that of hexaploid common wheat.     

Modulation of nucleobindin-1 and nucleobindin-2 by caspases

Nucleobindin-1 (NUCB1) and nucleobindin-2 (NUCB2) are multifunctional proteins that interact with Ca(2+), nucleic acids and various regulatory proteins in different signaling pathways. So far, our understanding of the regulation of the biological functions of nucleobindins remains limited. In our proteome-wide selection for downstream caspase substrates, both NUCB1 and NUCB2 are found to be the downstream substrates of caspases. We report here the detailed analyses of the cleavage of nucleobindins by caspases. Significantly, the caspase cleavage sites are located exactly at one of the Ca(2+)-binding EF-hand motifs. Our results suggest that the functions of nucleobindins could be modulated by caspase-mediated cleavage in apoptosis.     

Changes in ribonucleoprotein particle and chromatin organization induced by liposomes in isolated nuclei

Nuclei isolated from rat liver, incubated in the presence of liposomes of different phospholipids, undergo typical modifications: chromatin dispersion and reduction of the interchromatin granules in nuclei incubated with negatively charged liposomes and increase of the chromatin density and of the number and size of the interchromatin granules in nuclei incubated with neutral liposomes. The possibility that the observed modifications are caused by an impairment of the transport and translocation of ribonucleoproteins belonging to the inner nuclear matrix, is suggested by the results obtained by radiotracer techniques on the release of RNA from liposome-incubated nuclei.     

甲状腺转录因子-1融合表达载体的构建及体外活性鉴定

目的:构建人甲状腺转录因子-1(TTF1)编码基因的真核表达载体pcDNA3.1/myc-His(-)C-TTF1,并观察其蛋白质体外转录翻译情况。方法:据已知的TTF1基因序列,应用巢式PCR技术,从人肺腺癌细胞株SPC-A1中扩增出TTF1基因,通过TA连接将其克隆入pGEM-T-easy载体,经测序鉴定后,双酶切插入真核表达质粒pcDNA3.1/myc-His(-)C中;重组质粒经XhoⅠ和BamHⅠ双酶切鉴定后,进行蛋白质体外翻译观察TTF1体外表达情况,用电泳迁移率变动分析(EMSA)验证获得的体外翻译蛋白TTF1是否具有与下游靶基因UGRP1启动子结合的能力。结果:成功构建了含TTF1编码基因的真核表达载体pcDNA3.1/myc-His(-)C-TTF1,并能在体外表达TTF1蛋白。结论:能方便地获得TTF1体外翻译蛋白,为进一步研究TTF1蛋白与相应的DNA反应元件及其他转录因子的相互作用奠定了基础。