一种从人体胚胎中分离纯化的限制性核酸内切酶HsaI

从人、Homo sapiens、胚胎组织及细胞核的抽提物中分离纯化了一种核酸内切酶HsaI。它具有Ⅱ类核酸内切酶的功能、从该酶对λDNA的切割位点来看,它是EcoRI的同功酶,但在洗脱特性上不同于EcoRI。经SDS-聚丙烯酰胺凝胶电泳分析可得两条考马氏兰染色带,分子量分别为65000和22000 Daltons。     

CONSTRUCTIONS OF GENE LIBRARIES OF RANA NIGROMACULATA AND MUS MUSCULUS WITH COSMID pHC79

Gene libraries of Rana nigromaculata and Mus musculus (C_(57)J_6) have been constructed bythe cosmid system developed by Collins using BamHl and Pstl as cloning restriction enzymes.A simplified formula, which is a modification of Clarke and Carbon derived from apprixima-tion, was used for calculating the number of colonies or recombinants necessary for theconstruction of a gene library. Pro~ and leu~ complementary to the recipient cells (RB101)with the genetic constitution of pro~- and leu~- have been selected from the BamHl genelibraries of both Rana nigromaculata and the mouse in the present work.     

黑斑蛙(Rana nigromaculata)和小鼠(Mus musculus)基因文库的构建

本文采用了Collins所建立的Cosmid方法,用内切酶Bam HI和Pst I,建立了黑斑蛙和小鼠的Bam HI及Pst I的基因文库,这些基因文库所需的菌落数或重组的杂种DNA片段数是根据作者用近似法求得的公式计算的,这公式适用于高等动植物。文中还利用Cosmid受体细胞的营养缺陷性质,分离出互补于这些缺陷的基因。     

HsaI: A RESTRICTION ENZYME FROM HUMAN BEING

The HsaI restriction enzyme from the embryos of human, Homo sapiens, has been isolated with both the tissue extract and nnelear extract. It proves to be an unusual enzyme, clearly related functionally to Type Ⅱ endonuclease. HsaI seems to be an isoschizomer of EcoRI, but it has a distinctive property of elation, differing from EeoRI. Upon SDS-polyacrylamide gel electrophoresis, the enzyme preparation showed Coomassie blue staining bands, having the molecular weight of 65,000 and 22,000 daltons in size, respectively.     

黑麦和水稻与脯氨酸合成有关的基因片段的克隆和鉴定

用大肠杆菌营养缺陷互补法得到了含黑麦和水稻染色体DNA片段能互补于proA2~-的转化体.在渗透胁迫下,黑麦和转化体中这些片段的转录物都有明显增加,转化体中游离脯氨酸量也增加了.转化体的抗旱抗盐能力明显优于对照菌.初步分析,所克隆的片段和植物的调渗作用有关.