一种新的cDNA克隆的分析及可能功能推测

筛选胎儿心脏文库时发现一个新cDNA,Genbank搜索和BLAST表明该断cDNA和蛋白激酶A锚定蛋白AKAP95有71％的蛋白质相似性,且在3′端存在一个锌指结构和AKAP基因特有的RⅡ结合区域,因此初步判定该新cDNA为一种AKAP基因;该cDNA和人类19号染色体的一段区域相同,HGP计划标明在cosmid R33907和cosmid F20900上,而该个粒定位在19号染色体的q13．1处,因此将该新基因定位于人第19号染色体的q13．1处,并且同AKAP95相邻。     

RACE理论研究及其在植物基因工程中的应用

cDNA末端快速扩增—RACE(rapid amplification of cDNA ends),是近年发展起来的快速有效的获得全长cDNA的途径之一。本文阐述了RACE的历史、技术原理、局限性以及新型的RACE技术,并且讨论了RACE技术在植物基因研究中的技术优势、应用现状和发展前景。     

Nervous tissue proteoglycans

The structure, biosynthesis, localization, and possible functional roles of nervous tissue glycosaminoglycans and proteoglycans were last reviewed several years ago^70,74. Since that time, there has been an exponential increase in publications on the neurobiology of proteoglycans. This review will therefore focus on reports which have appeared in the period after 1988, and especially on those concerning the properties of individual characterized nervous tissue proteoglycans. Related areas such as the regulation of glycosaminoglycan biosynthesis and the roles of cell surface proteoglycans in adhesion and growth control are covered in other contributions to this special topic issue.     

Molecular pathology and pathobiology of osteoarthritic cartilage

The biochemical properties of articular cartilage rely on the biochemical composition and integrity of its extracellular matrix. This matrix consists mainly of a collagen network and the proteoglycan-rich ground substance. In osteoarthritis, ongoing cartilage matrix destruction takes place, leading to a progressive loss in joint function. Beside the degradation of molecular matrix components, destabilization of supramolecular structures such as the collagen network and changes in the expression profile of matrix molecules also take place. These processes, as well as the pattern of cellular reaction, explain the pathology of osteoarthritic cartilage degeneration. The loss of histochemical proteoglycan staining reflects the damage at the molecular level, whereas the supramolecular matrix destruction leads to fissuring and finally to the loss of the cartilage. Chondrocytes react by increasing matrix synthesis, proliferating, and changing their cellular phenotype. Gene expression mapping in situ and gene expression profiling allows characterization of the osteoarthritic cellular phenotype, a key determinant for understanding and manipulating the osteoarthritic disease process.     

忽地笑(Lycoris aurea)叶片cDNA文库的构建与分析

用表达型噬菌体载体ZAP构建了忽地笑叶片cDNA文库。文库宿主菌为E.coliXL1 BLUE,亚克隆空菌为E.coliXLOLR。初始文库的滴度为5.6×105pfu/mL,扩增文库的滴度为6.9×109pfu/mL,含插入片段的频率为96%,插入片段大小在0.5～2.5kb,文库质量良好。为进一步从基因组学和分子生物学方面研究忽地笑叶片发育及克隆相关全长基因奠定了基础。     

杨树黑斑病感抗无性系cDNA文库的构建

为了分离与抗病相关的目的基因,以病原菌接种后对黑斑病具免疫力的美洲黑杨I 69及黑斑病的高感无性系欧美杨I 45的叶片为材料,在利用荧光差异显示反转录聚合酶链式反应(DDRT PCR)获得抗病相关cDNA片段的基础上,用试剂盒及同样的植物材料构建了两个cDNA文库L45 72及L69 72。两文库的滴度分别为3.44×109pfu/mL及3.94×109pfu/mL,大于500bp的片段分别占96.67%和73.33%。     

中华绒螯蟹卵巢新基因EJO5的全长cDNA克隆和序列分析

利用RACE技术从中华绒螯蟹卵巢获得了新基因EJO5 (Eriocheirjaponicaovarygene 5 ,EJO5 )的全长cD NA序列 (GenBank检索号 :AY185 92 1) .该cDNA序列长度为 14 2 5bp ,开放阅读框为 5 85bp ,编码 194个氨基酸 .根据氨基酸序列计算的相对分子质量和等电点分别为 2 2 3 44和 9 5 .用生物信息学的方法未能得到对该基因功能预测的信息 .     

兔生长激素cDNA克隆和表达

从兔脑下垂体中的mRNA中,利用合成引物逆转录PCR,获得了前体和成熟生长激素的cDNA,成熟生长激素的cDNA克隆在pET-3a表达载体并转化到大肠杆菌BL21(DE3 plys)中,获得了高效表达,表达量达到大肠杆菌总蛋白的40%。