α-半乳糖苷酶

最近各种媒体不断报道红血球类型可以通过酶处理进行转换 ,这对于输血和开拓血源有十分重要的意义 ,所用的酶是α 半乳糖苷酶。α 半乳糖苷酶 (α ｇａｌａｃｔｏｓｉｄａｓｅ ,α Ｄ ｇａｌａｃｔｏｓｉｄｅｇａｌａｃｔｏｈｙｄｒｏｌａｓｅ ,ＥＣ 3.2 .1 .2 2 )能专一地催化α 半乳糖苷键的水解。它广泛存在于各种植物和动物体内 ,许多微生物如双歧杆菌 (Ｂｉｆｉｄｏｂａｃｔｅｒｉｕｍ)、黑曲霉菌 (Ａｓｐｅｒｇｉｌｌｕｓｎｉｇｅｒ) [1] 、大肠杆菌 (Ｅｓｃｈｅｒｉｃｈｉａｃｏｌｉ)Ｋ 1 2 1 [2 ]的抽提液中也发现有α 半乳糖苷酶的…     

dsRNA介导的RNA干扰

在多种生物中 ,外源或内源性的双链ＲＮＡ(ｄｏｕｂｌｅ ｓｔｒａｎｄｅｄＲＮＡ ,ｄｓＲＮＡ)导入细胞中 ,与ｄｓＲＮＡ同源的ｍＲＮＡ则受到降解 ,因而其相应的基因受到抑制。这种转录后基因沉默 (ｐｏｓｔ ｔｒａｎｓｃｒｉｐｔｉｏｎａｌｇｅｎｅｓｉｌｅｎｃｉｎｇ ,ＰＴＧＳ)机制首先在线虫 (Ｃ .ｅｌｅｇａｎｓ)中得以证实。由于这是一种在ＲＮＡ水平的基因表达抑制 ,故也称为ＲＮＡ干扰 (ＲＮＡｉｎｔｅｒｆｅｒ ｅｎｃｅ) ,简称ＲＮＡｉ[1] 。随后发现 ,在各种生物 ,如果蝇[2 ] 、拟南芥菜[3 ] 、及小鼠[4] 等均存在ｄｓＲＮＡ介导…     

茶毛虫核型多角体病毒（EpNPV）多角体蛋白基因的定位及克隆

茶毛虫核型多角体病毒 (Ｅｕｐｒｏｃｔｉｓｐｓｅｕｄｏｃｏｎｓｐｅｒ ｓａＮｕｃｌｅａｒＰｏｌｙｈｅｄｒｏｓｉｓＶｉｒｕｓ简称ＥｐＭＰＶ) ,属于杆状病毒科核型多角体病毒属 ,能使茶毛虫染病死亡。ＥｐＮＰＶ据报道最初由日本学者于 195 7年发现[1] ,随后在其它国家和地区也有相关报道[2 ] ;我国在贵州、湖北、广西和云南等地也有发现 ,并在ＥｐＮＰＶ病毒杀虫剂的大田应用方面做了大量的工作 ,取得了一定的社会、经济和生态效益[3] 。本文以苜蓿丫纹夜蛾多粒包埋核型多角体病毒(ＡｕｔｏｇｒａｐｈａｃａｌｉｆｏｒｎｉｃａＭＮＰＶ…     

链霉菌的可转座因子

可转座因子是细菌遗传分析和分子操作十分有用的工具 ,它包括插入序列、转座子和转座噬菌体。细菌的可转座因子多数来自于革兰氏阴性菌 ,少数来自于革兰氏阳性菌。链霉菌是一类重要的革兰氏阳性菌 ,近年来 ,已发现了几种链霉菌的可转座因子 ,并对部分可转座因子的转座特征作了详细的研究。最早发现的链霉菌可转座因子是天蓝色链霉菌 (Ｓ .ｃｏｅｌｉｃｏｌｏｒ)Ａ3( 2 )中 1 6ｋｂ的插入片断ＩＳ1 1 0 [1 ] ,后来在白色链霉菌 (Ｓ .ａｌｂｕｓ)中发现了ＩＳ1 1 2 [2 ] ,在带棒链霉菌 (Ｓ .ｃｌａｖｕｌｉｇｅｒｕｓ)中发现了ＩＳ1 1 6[3] ,…     

AN ANALYSIS OF RELATIVE FATNESS OF THE CAPE HARE( LEPUS CAPENSIS)

Ｂｏｄｙｃｏｎｄｉｔｉｏｎｉｓｏｎｅｏｆｔｈｅｉｎｄｉｃａｔｏｒｓｏｆｗｉｌｄｌｉｆｅｐｏｐｕｌａｔｉｏｎｓｔａｔｕｓ.Ｋｉｄｎｅｙｆａｔｉｎｄｅｘ[1 ] ａｎｄｗｅｉｇｈｔ ｌｅｎｇｔｈｉｎｄｅｘ (ｂｏｄｙｗｅｉｇｈｔａｇａｉｎｓｔｃｕｂｅｂｏｄｙｌｅｎｇｔｈ) [2 ] ａｒｅｔｗｏｃｏｍｍｏｎｉｎｄｉｃａｔｏｒｓｆｏｒｓｐｅｃｉｅｓｏｆｌａｇｏｍｏｒｐｈ .Ｔｈｅｌａｔｔｅｒｉｓｍｏｒｅｃｏｎｖｅｎｉｅｎｔｔｏｍｅａｓｕｒｅｉｎｇａｍｅｍａｎａｇｅｍｅｎｔｐｒａｃｔｉｃｅ.Ｔｈｉｓｐａｐｅｒａｎａｌｙｚ…     

不同培养方法对木槿原生质体培养的影响

本文研究了不同培养方法对木槿 (Ｈｉｂｉｓｃｕｓｓｙｒ ｉａｃｕｓ)原生质体培养的影响。种子采自本校校园 ,原生质体分离按朱启忠[1] 和Ｎｏｍｕｒａ[2 ] 的方法。培养方法有 :(1)液体浅层 (培养皿中加入 3ｍｌ培养液 ) ;(2 )固液双层 (固体层用 0 .4 %的琼脂及 0 .3%琼脂糖     

蚓激酶的克隆及其对BHK细胞的作用

蚯蚓具有活血化瘀的功效 ,在我国作为中药 (地龙 )使用已经有上千年的历史 .近年来发现蚯蚓体内存在溶血栓成分 ,称为蚓激酶 (ｌｕｍｂｒｕｋｉｎａｓｅ)或蚯蚓纤溶酶 (ｔｈｒｏｍｂｏｌｙｔｉｃｅｎｚｙｍｅｉｎｅａｒｔｈｗｏｒｍ) .自Ｎ .Ｎａｋａ ｊｉｍａ报道从蚯蚓中分离到蚓激酶以来[1] ,国内外已经有许多报道[2～ 6] ,主要侧重于天然提取物的生化研究 .本文通过ＲＴ ＰＣＲ从蚯蚓 (Ｌ .ｂｉｍａｓｔｕｓ)体内获得蚓激酶基因 ,进行表达并观察其对ＢＨＫ细胞的作用 .1　材料与方法1 1　材料正蚓科双胸蚓属蚯蚓 ;反转录试剂 ,质粒ｐｃ…     

Longgupo Hominoid Mandible Belongs to Ape

Ｉｎ 1 991 ,Ｈｕａｎｇｅｔａｌ.[1] ａｔｔｒｉｂｕｔｅｄｔｈｅＬｏｎｇｇｕｐｏｍａｎｄｉｂｌｅｔｏＨｏｍｏｅｒｅｃｔｕｓ ,ａｎｄｔｈｅｎｌａｔｅｒ[2 ]ｓｕｇｇｅｓｔｅｄｉｔｗａｓｃｌｏｓｅｔｏＨｏｍｏｅｒｇａｓｔｅｒ.ＷｏｏｄａｎｄＴｕｒｎｅｒ[3] ａｇｒｅｅｄｔｈｉｓａｔｔｒｉｂｕｔｉｏｎ .ＬａｒｉｃｋａｎｄＣｉｏ ｃｈｏｎ[4 ] ａｓｗｅｌｌａｓＣｉｏｃｈｏｎ[5] ａｔｔｒｉｂｕｔｅｄｉｔｔｏＨｏｍｏ .ＴｈｅｈｏｍｉｎｉｄｓｔａｔｕｓｈａｓｂｅｅｎｃｈａｌｌｅｎｇｅｄｂｙＷｏｌｐｏｆｆ[6 ] ,ＳｃｈｗａｒｔｚａｎｄＴａｔｔｅｒｓａｌｌ[7] ａｎｄＰｏｐｅ[8] ,ａｓｗｅｌｌａｓｂｙＥｔｌｅｒａｎｄＺｈｏｕ[9] ｗｈｏｆｕｒｔｈｅｒｉｎｄｉｃａｔ ｅｄａｎａｎｃｅｓｔｏｒ ｄｅｓｃｅｎｄｅｎｔｒｅｌａｔｉｏｎｓｈｉｐｂｅｔｗｅｅｎＬｕｆｅｎｇｐｉｔｈｅｃｕｓａｎｄｔｈｅＬｏｎｇｇｕｐｏｍａｎｄｉｂｌｅ .Ｂｕｔｔｈｅｒｅｉｓｎｏｄｅｔａｉｌｅｄｄｉｓｃｕｓｓｉｏｎｉｎａｎｙｏｆｔｈｅｓｅａｒｔｉｃｌｅｓ.Ｔｈｅｐｒｅｓｅｎｔａｕｔｈｏｒｗｏｕｌｄｌｉｋｅｔｏｐｒｅｓｅｎ...     

Isolation and mapping of bacterial artificial chromosome (BAC) clone containing telomere-associated sequence

Ｔｅｌｏｍｅｒｅｓａｒｅｔｈｅｅｎｄｓｏｆｔｈｅｅｕｋａｒｙｏｔｉｃｃｈｒｏｍｏｓｏｍｅｓａｎｄｃｏｎｓｉｓｔｏｆｔａｎｄｅｍｌｙｓｈｏｒｔｒｅｐｅａｔｓｅｑｕｅｎｃｅｓｗｈｉｃｈａｒｅｄｅｓｃｒｉｂｅｄｂｙｔｈｅｃｏｎｓｅｎｓｕｓ[ｄ(Ｔ/Ａ)14ｄＧ18]ｎｉｎｍｏｓｔｏｒｇａｎｉｓｍｓ.ＴｈｅｔｅｌｏｍｅｒｉｃｒｅｐｅａｔｓｏｆＡｒａｂｉｄｏｐｓｉｓ,[ＴＴＴＡＧＧＧ]ｎ,ｗｅｒｅｃｌｏｎｅｄｉｎ1988[1].Ｇａｎａｌｅｔａｌ.[2]ｒｅｐｏｒｔｅｄｔｈｅｔｏｍａｔｏｔｅｌｏｍｅｒｅｓｅｑｕｅｎｃｅ,[ＴＴ(Ｔ/Ａ…     

CHANGES IN DISTRIBUTION OF AMUR GORAL (NEMORHAEDUS CAUDATUS) IN SOUTH KOREA

Ａｍｕｒｇｏｒａｌ (Ｎｅｍｏｒｈａｅｄｕｓｃａｕｄａｔｕｓ)ｉｓａｒａｒｅｓｐｅｃｉｅｓａｍｏｎｇＡｓｉａｎｍａｍｍａｌｓ.ＩｔｉｓｌｉｓｔｅｄａｓＶｕｌｎｅｒａｂｌｅｉｎｔｈｅ 1 996ＩＵＣＮＲｅｄＬｉｓｔｏｆｔｈｅＴｈｒｅａｔｅｎｅｄＡｎｉｍａｌｓ[1 ] ,ａｎｄｄｅｓｉｇｎａｔｅｄａｓｔｈｅｎａｔｕｒａｌｍｏｎｕｍｅｎｔ (Ｎｏ.2 1 7)ｉｎＲｅｐｕｂｌｉｃｏｆＫｏｒｅａ[2 ] .ＴｈｉｓｓｐｅｃｉｅｓｉｓｄｉｓｔｒｉｂｕｔｅｄｉｎＮｏｒｔｈｅａｓｔａｎｄＳｏｕｔｈ ｗｅｓｔｏｆＣｈｉｎａ ,ｓｏｕｔｈｏｆｔ…     

Identification of a putative gamma-aminobutyric acid (GABA) receptor subunit rho2 cDNA and colocalization of the genes encoding rho2 (GABRR2) and rho1 (GABRR1) to human chromosome 6q14-q21 and mouse chromosome 4.

Screening of a genomic DNA library with a portion of the cDNA encoding the gamma-aminobutyric acid (GABA) receptor subunit rho1 identified two distinct clones. DNA sequencing revealed that one clone contained a single exon from the rho1 gene (GABBR1) while the second clone encompassed an exon with 96% identity to the rho1 gene. Screening of a human retina cDNA library with oligonucleotides specific for the exon in the second clone identified a 3-kb cDNA with an open reading frame of 1395 bp. The predicted amino acid sequence of this cDNA demonstrates 30 to 38% similarity to alpha, beta, gamma, and delta GABA receptor subunits and 74% similarity to the GABA rho1 subunit suggesting that the newly isolated cDNA encodes a new member of the rho subunit family, tentatively named GABA rho2. Polymerase chain reaction (PCR) amplification of rho1 and rho2 gene sequences from DNA of three somatic cell hybrid panels maps both genes to human chromosome 6, bands q14 to q21. Tight linkage was also demonstrated between restriction fragment length variants (RFLVs) from each rho gene and the Tsha locus on mouse chromosome 4, which is homologous to the CGA locus on human chromosome 6q12-q21. These two lines of evidence confirm that GABRR1 and newly identified GABRR2 map to the same region on human chromosome 6. This close physical association and high degree of sequence similarity raises the possibility that one rho gene arose from the other by duplication.     

Garlic (Allium sativum) chitinases: characterization and molecular cloning

Leaves and bulbs of garlic ( Allium sativum L.) contain a chitinase which can be separated into three different isoforms with similar molecular structure and N- terminal amino acid sequence. SDS-PAGE of the alkylated chitinase revealed two distinct polypeptides of 32 and 33 kDa. Induction studies of the chitinase in leaves of garlic plants indicated that not only treatment with ethephon or salicylate and wounding but also a temperature shock strongly increased the enzyme level.
cDNA libraries constructed from poly(A)-rich RNA isolated from young garlic shoots and bulbs were screened for chitinase clones using the cDNA clone CCH4 encoding a basic potato chitinase as a probe. Two different cDNA clones (designated CHITAS 1 and CHITAS 2)of ca 1 000 bp were isolated and their sequences analyzed. The amino acid sequences deduced from both cDNA clones were homologous though not identical to the N-terminal sequences of the mature chitinases. Although both clones encode highly homologous chitinases their sequences definitely differ in that they have different signal peptides and one of them contains a glycine-rich domain. The garlic chitinases are apparently translated from an mRNA of 1200 nucleotides which encodes a proprotein of approximately 32 or 33 kDa for CHITAS 1 and CHITAS 2, respectively. Co-translational removal of the signal peptide will result in a 30 (for CHITAS 1) or 31 kDa (for CHITAS 2) protein with an isoelectric point of 4. 94 (for CHITAS 1) or 6. 12 (for CHITAS 2). Garlic chitinases are encoded by a small gene family as shown by Southern blot analysis of genomic DNA isolated from garlic.
The garlic chitinases show a high degree of sequence homology to the previously isolated chitinases from dicotyledonous as well as monocotyledonous species, indicating that these proteins have been conserved from an evolutionary point of view.     

大豆11S球蛋白Gy5(A3B4)的基因克隆和序列分析

大豆11Ｓ球蛋白(Ｇｌｙｃｉｎｉｎ)是大豆种子的主要贮藏蛋白,分子量为360ｋＤ,由6对相同的蛋白亚基(每对亚基的分子量约60ｋＤ)构成。每对亚基又是由一个酸性Ａ肽(35～45ｋＤ)和一个碱性Ｂ肽(22ｋＤ)通过二硫键连接而成。Ａ肽和Ｂ肽源自同一个基因,即首先由一个大的ｍＲ?..     

Construction and Characterization of a Goat Mammary Gland cDNA Library

A lactating goat mammary gland cDNA library was constructed by using a modified commercially available cDNA library construction kit protocol. The resulting clones were sequenced and functionally analyzed through cross-species genomic comparison to assess (1) the capacity and functional quality of the constructed library for subsequent research and (2) the efficiency of the procedural modifications. The study resulted in the construction of a high-quality mammary gland cDNA library, which was characterized by (1) the total recombinants number of 1.4 × 10⁷ colony-forming units (cfus) that was at least 10 times greater than the number expected from the application of the standard kit protocol, (2) the recombinants rate of 96%, and (3) the average insert size of 1,082 bp. BLAST analysis of sequenced clones against GenBank databases determined 55.7% of clone redundancy, 22 known function gene clusters, and 29 novel gene clusters. The analysis of the primary gene expression profile showed that 59% of the tested clones were genes that coded for milk proteins while 16% of the clones coded for ribosomal, metabolism, immune response, and translation proteins. The remaining 25% of the tested clones were described as novel genes. Cross-species comparison showed that 77% of characterized gene clusters were successfully identified by using resources from other ruminants and unrelated species. This outcome is in consonance with the common belief that the genomic resources that have been generated across species are potentially powerful tools that could be used for enhancing the molecular understanding of less genomically studied species, such as goat.     

二倍体马铃薯蛋白酶抑制剂II基因的克隆、序列分析及表达载体的构建

根据GenBank发表的四倍体马铃薯栽培种(Solanum.tuberosum)来源的马铃薯蛋白酶抑制剂II基因序列,用PCR方法从二倍体马铃薯IVP101（Solanum.phurejia）cDNA文库和基因组DNA扩增得到马铃薯蛋白酶抑制剂II的cDNA和DNA,命名为PINII-2x。测序表明,PINII-2x基因组DNA全长580 bp,含有一个115 bp的内含子,cDNA有462 bp(除去终止密码子)。推测的PINII-2x分子量是16.6 kD,等电点6.08。与其他马铃薯蛋白抑制剂II同源性比较表明,核苷酸同源性高达88%;推测的氨基酸序列同源性为93%,并具有相同的活性中心。RT-PCR表明,PINII-2x的mRNA在叶片中具有强烈的伤害诱导表达特性。同时,构建了分别以水稻ActI启动子和玉米Ubi启动子驱动PINII-2x基因的双元载体。     

Isolation and mapping of rFUS6, a rice orthologue of Arabidopsis thaliana FUS6.

COP9 complex is one of the most important components that act in repressing photomorphogenesis in Arabidopsis thaliana. FUS6 has been identified as one of eight subunits of the COP9 complex in Arabidopsis. Using Arabidopsis Fus6 cDNA as a probe, we screened a rice root cDNA library and a rice genomic library. A 1730-bp cDNA was obtained, which has an open reading frame corresponding to 441-amino-acid. This 441 amino acids putative protein has 67% identity with Arabidopsis COP11/FUS6 (AtFUS6) and 40% identity with human GPS1, an AtFUS6 orthologue. So we designated this novel gene as rFUS6. The 6.2-kb genomic sequence of rFUS6 was also obtained. Sequence comparison showed that the rFUS6 gene had six exons and five introns. Sequence inspection of the 5'-flanking region revealed the presence of some potential light-regulated cis-elements such as a G-box, GT-1 binding sites, and a TGACG motif. Southern hybridization with rice total DNA showed that rFUS6 was perhaps a single copy gene. The rFUS6 locus was mapped by hybridization with a rice BAC library membrane and the results showed that rFUS6 had a locus at 16.3 cM of chromosome 1.