大鼠20αHSD基因调控序列的克隆与检测

酶切包含20αHSD基因及其调控序列的X噬菌体13NA,获得4．0kb的DNA大片段,将此片段与载体质粒连接得到重组质粒,酶切重组质粒后电泳,再以地高辛标记的20αHSD基因的cDNA为探针进行Southern杂交,实验获得了大片段的重组质粒。     

基于改进遗传算法的FISH基因模糊自适应提取

为了快速准确地提取荧光原位杂交（FISH）图像中的荧光染色基因,提高临床医学上诊断病变的效率,针对FISH图像固有的模糊特征,提出了一种基于改进遗传算法的多维多阈值模糊自适应提取算法.首先根据灰度直方图的分布特性,提出相应的自适应窗宽选取算法,确定阈值搜索的范围;然后通过设计的模糊隶属度函数,将图像分割成若干不同的区域;最后采用最大模糊熵准则,并借助优化后的自适应遗传算法,寻找确保基因目标最大信息量的分割阈值.将分割结果与其他几种常用分割算法进行比较,并采用分类概率的数学测量方法定量分析,结果表明：在标准噪声干扰下,该算法的错误划分概率仅为0.042 1,可以更加准确和高效地对荧光基因进行提取.     

导入额外拷贝dctA基因的根瘤菌工程菌株的构建

为进一步提高大豆根瘤菌的固氮能力,以费氏中华根瘤菌(Sinorhizobium fredii)15067基因组的DNA作为模板,采用PCR扩增技术,克隆四碳二羧酸转移酶结构基因dctA的全长序列;将其连入lac启动子下游,构建带有LuxAB基因标记的pTR-Plac-dctA重组表达载体。利用三亲本杂交技术将表达载体转入费氏中华根瘤菌中,构建大豆根瘤菌工程菌株。研究表明,转基因工程菌株侵染大豆幼苗后与出发菌相比,固氮酶活性有了显著提高,为提高大豆产量的研究提供一定参考。     

p53基因在小鼠胚胎发育过程中的表达

以E9日龄至E14日龄昆明种正常小鼠胚胎为材料,利用质粒扩增的、地高辛标记的基因探针在组织切片上进行DNA-mRNA 分子原位杂交,研究了p53基因在小鼠胚胎发育过程中的表达.结果表明, p53基因不参与E9和E10日胚胎发育中的器官原基形成,参与器官的进一步分化成熟过程.这些器官主要有眼、脑、心、肺、脊柱和面颌骨,肝组织的发育与其无关; p53基因一方面参与胚胎发育中的细胞周期调控,另一方面也参与了某些与细胞周期无关的过程;不同的器官有不同的细胞周期调控机制.     

In situ localization of calmodulin mRNA in the developing tobacco anthers

The temporal and spatial expression patterns of calmodulin mRNA in the developing tobacco anthers were investigated by in situ RNA hybridization, using digoxigening-labeled anti-RNA probe. Calmodulin mRNA was distributed in various developmental stages of tobacco anthers, but the expression level had temporal and spatial differences distinctly. During early stage of anther development, the expression level of calmodulin mRNA was significantly high, mainly distributed in epidermis, tapetum and transfusion parenchyma cells and so on. Especially, more mRNA was accumulated in the nuclei and chromosomes of microspore mother cells prior to and during meiosis. With the development of anther, mRNA was decreased gradually in the anther wall and pollen. By mature pollen stage, only a stronger positive reaction still existed in the epidermis of anther wall and transfusion parenchyma cells. The results suggest that the temporal and spatial expression of calmodulin mRNA is closely correlated with cell division, pollen development and substance transport.     

缺铁玉米根cDNA文库的构建及蛋白和cDNA差异比较

采用异硫氰酸胍酚氯仿法分离铁胁迫玉米根总ＲＮＡ,然后采用寡聚ｄＴ 纤维素层析柱法纯化Ｐｏｌｙ（Ａ） ＋ ＲＮＡ．用含有ＸｈｏＩ位点的ｌｉｎｋｅｒｐｒｉｍｅｒ 锚定合成ｃＤＮＡ 第一条链后,采用替代法合成第二条链,接着连接上ＥｃｏＲＩＡｄａｐｔｅｒ 以便定向重组到载体上．ｃＤＮＡ 经过ＸｈｏＩ消化和分级分离后,带有ＸｈｏＩ和ＥｃｏＲＩ粘性末端的ｃＤＮＡ 定向重组到λＺＡＰ表达载体的ＸｈｏＩ和ＥｃｏＲＩ位点上．经体外包装,重组的噬菌体转导宿主菌ＸＬ１Ｂｌｕｅ ＭＲＦ,最终获得滴度为４－５ ×１０５ ｐｆｕ／ｕｇ 的λＺＡＰ 表达ｃＤＮＡ 文库．通过差异筛选法和质膜双向电泳验证了缺铁和加铁条件下ｃＤＮＡ 和质膜蛋白的差异     

单倍体小麦与簇毛麦的不对称体细胞杂交

以小麦杂２４２（Ｔｒｉｔｉｃｕｍａｅｓｔｉｖｕｍ,ｃｖ．２４２）花药来源的愈伤组织分离原生质体作受体;簇毛麦（Ｈａｙｎａｌｄｉａｖｉｌｏｓａ）幼胚来源的愈伤组织原生质体经２２０μＷ／ｃｍ２紫外线照射３０ｓ作供体,用ＰＥＧ法诱导融合,最后获得再生愈伤组织．对融合再生的４个最先长大的细胞系进行染色体,同工酶和ＲＡＰＤ分析．结果表明,这些细胞系均为体细胞杂种,ＲＡＰＤ技术可作为小麦体细胞杂种早期鉴定的有效方法     

rhGM-CSF/IL-3融合蛋白中残余菌体DNA的检测

本文利用地高辛标记及检测试剂盒,标记ｐｏｐ２１３６（ＰＭＴＧ３）工程菌染色体ＤＮＡ作为探针,检测基因工程药品重组人粒细胞－巨噬细胞集落刺激因子／白细胞介素－３（ｒｈＧＭ－ＣＳＦ／ＩＬ－３）融合蛋白中残余的菌体ＤＮＡ．结果符合质量标准每剂＜１００ｐｇ．     

Chromosomalin situ hybridization ofCyprinus carpio genomic DNA repetitive sequence CR1

Common carpCyprinus carpio genomic DNA repetitive sequence CR1 has been DIG-labeled and hybridizedin situ against chromosomes of red common carp (Cyprinus carpio L. Xingguo red var. ). It is found that the repetitive sequence CR1 is mainly localized at the centromeric regions of chromosomes of the red common carp. The application of the chromosomalin situ hybridization technique on fish and the relationship between CR1 repetitive sequence distribution and its function have been discussed.