PRPS2基因启动子区的单核苷酸多态性(英文)

人类基因组变异主要以单核苷酸多态性 (SNPs)为主 .采用多荧光标记的PCR单链构象多态性分析法 (MF PCR SSCP)对磷酰核糖焦磷酸合成酶亚基Ⅱ (PRPS2 )基因启动子区的序列进行了SNP的筛选 ,对筛选到的阳性片段进行序列分析以确定SNP的类型及位置 .在 1 5kb的启动子区发现了 2个SNP (- 10 79t c ,- 1110a g) .研究结果为PRPS2基因SNPs的数据库提供了新的信息 .     

The cDNA encoding Xenopus laevis heat-shock factor 1 (XHSF1): nucleotide and deduced amino-acid sequences, and properties of the encoded protein

We have isolated a cDNA encoding Xenopus laevis (Xl) heat-shock factor 1 (XHSF1). XHSF1, translated from the mRNA synthesized in vitro, will bind specifically to the X1 hsp70 promoter (hsp70). Microinjection of XHSF1 mRNA into Xl oocytes leads to synthesis of XHSF1 which accumulates in the nucleus and selectively activates Xl phsp70p activity at 18°C.     

Cloning, nucleotide sequence and high level expression of the gene coding for the connector protein of Bacillus subtilis phage φ 29

The φ 29 DNA restriction fragment HindIII-D, shown to contain gene 10 coding for the connector protein, has been cloned in plasmid pPLc28 under the control of the p_L promoter of phage λ. After heat induction to inactivate the λ repressor, a protein with the electrophoretic mobility of the connector protein p 10 was synthesized, accounting for about 30 % of the total Escherichia coli protein after 3 h of induction. The 2205 nucleotide-long sequence of the cloned HindIII-D fragment has been determined. The sequenced region has an ORF coding for a protein of M_r 35881 that was shown to correspond to the connector protein by determination of the ammo-terminal sequence of purified protein p10. Features of the nucleotide sequence and the amino acid sequence of protein p10 are discussed.     

Plasmid vector pBR322 and its special-purpose derivatives — a review

The plasmid pBR322 was one of the first EK2 multipurpose cloning vectors to be designed and constructed (ten years ago) for the efficient cloning and selection of recombinant DNA molecules in Escherichia coli. This 4363-bp DNA molecule has been extensively used as a cloning vehicle because of its simplicity and the availability of its nucleotide sequence. The widespread use of pBR322 has prompted numerous studies into its molecular structure and function. These studies revealed two features that detract from the plasmid's effectiveness as a cloning vector: (a) plasmid instability in the absence of selection and, (b) the lack of a direct selection scheme for recombinant DNA molecules. Several vectors based on pBR322 have been constructed to overcome these limitations and to extend the vector's versatility to accomodate special cloning purposes. The objective of this review is to provide a survey of these derivative vectors and to summarize information currently available on pBR322.     

Cloning and characterization of KM190, a specific satellite DNA family of Drosophila kitumensis and D. microlabis.

The nucleotide sequences of nine clones, pKA191/l-4 from Drosophila kitumensis and pMR.190/1–5 from D. microlabis, were determined. They represent a tandemly arranged and highly repetitive satellite DNA family, KM190, which is specific for the two species.     

Cloning and characterization of KM190, a specific satellite DNA family of Drosophila kitumensis and D. microlabis

The nucleotide sequences of nine clones, pKA191/l-4 from Drosophila kitumensis and pMR.190/1–5 from D. microlabis, were determined. They represent a tandemly arranged and highly repetitive satellite DNA family, KM190, which is specific for the two species.     

The lipoprotein lipase-encoding human gene: sequence from intron-6 to intron-9 and presence in intron-7 of a 40-million-year-old Alu sequence.

The complete nucleotide sequence of the 3877-bp segment spanning the 3′ region of intron-6 to the 5′ region of intron-9 of the human lipoprotein lipase (LPL)-encoding ten-exon gene, LPL, is reported. An Alu repeat present in intron-7 was found by sequence analysis to belong to the 40–55-million-year-old Alu-Se subclass.     

The lipoprotein lipase-encoding human gene: sequence from intron-6 to intron-9 and presence in intron-7 of a 40-million-year-old Alu sequence

The complete nucleotide sequence of the 3877-bp segment spanning the 3′ region of intron-6 to the 5′ region of intron-9 of the human lipoprotein lipase (LPL)-encoding ten-exon gene, LPL, is reported. An Alu repeat present in intron-7 was found by sequence analysis to belong to the 40–55-million-year-old Alu-Se subclass.     

利用5型腺病毒晚期启动子在真核细胞中表达乙型肝炎病毒表面抗原

近年来,随着基因工程研究工作的迅速发展,病毒载体越来越受到重视。用腺病毒(AdV)做载体也早已有人研究。Carl Thummel等构建了AdV-SV40重组体,在AdV晚期启动子控制下表达SV40T抗原。我们用AdV5晚期启动子(LLP)构建了一个新的质粒。用SV40启动neo基因做为真核细胞筛选标志,用AdV5 LLP在Vero细胞内表达HBsAg。并单独用AdV5LLP代替SV40早期启动子,在Vero细胞内表达neo基因。     

微生物代谢工程原理与应用

代谢工程是利用分子生物学原理系统分析细胞代谢网络,并通过DNA重组技术和应用分析生物学相关的遗传学手段对细胞进行有精确目标的基因操作,改变微生物原有的代谢或调节系统,实现目的产物代谢活性的提高。代谢工程综合了生物化学、化学工程、数学分析等多学科内容,是当前国内外学者研究热点之一。论述了微生物代谢工程的理论基础及其应用进展和前景。     

The Cucurbita maxima ribosomal DNA intergenic spacer has a complex structure

The nucleotide (nt) sequence of the 5508-nt intergenic spacer (IGS), between the 25S- and the 18S-coding regions of Cucurbita maxima rDNA, was determined. The fragment sequenced is 6142 nt long and includes 472 nt of 25S- and 162 nt of 18S-coding regions. The IGS has a complex primary structure, composed of five repetitive families (A-E) and three unique domains. It is dominated by the presence of nine, tandemly-repeating units of approximately 250 nt (repeat D), each unit containing four copies of an internal subrepeat (repeat E). The repetitive units show sequence variability consisting of nt changes, insertions and deletions. Upstream of the nine D repeats and between two copies of the B repeat is a 575-nt region, highly G + C rich (83%) and heavily biased toward C (58%) in the sense strand. Within this region are six repetitive units, averaging 42 nt (repeat C) each, containing but a single A nt. Downstream from the terminus of the 25S-coding sequence, are two tandem copies of the 103-nt A repeat. The IGS of C. maxima is longer and more complex than that of other plant IGSs described to date. The 600 nt at the 5' portion of cucurbit IGS is more conserved in evolution than the remainder, as revealed by comparison of C. maxima and C. pepo IGS restriction maps and by nucleotide sequence comparison of C. maxima and Cucumis sativa IGSs.     

The cleavage site for the restriction endonuclease EcoRV is 5′-GAT/ATC-3′

The cleavage site for the restriction endonuclease EcoRV has been found to be 5′-GAT/ATC-3′, rather than 5′-GATAT/C-3′ as reported earlier by Kholmina et al. [Dokl. Akad. Nauk. 253 (1980) 495–497].