一个人类新基因ZNF322的研究初报

利用果蝇心脏发育基因zfh-1的cDNA序列和计算机克隆方法,在9号染色体上发现了一个新的人类同源基因,经国际基因全程委员会批准,命名为ZNF322。该基因总长度约为2.8kb,为一个连续的序列,编码一个402个氨基酸的蛋白质,与小鼠zfp-25编码的蛋白质最相似（同源度为51.4%）。该基因在人体肾、脑、结肠、胚胎心脏及黑色素瘤等多种组织中广泛表达,其功能有等深入研究。     

日本血吸虫26kD抗原基因在BCG中的表达

研究了外源基因日本血吸虫２６ｋＤ抗原（Ｓｊ２６ＧＳＴ）在卡介苗（ｂａｃｉｌｕｓＣａｌｍｅｔｅ－Ｇｕｅｒｉｎ,ＢＣＧ）、耻垢分枝杆菌（Ｍ．ｓｍｅｇｍａｔｉｓ）和大肠杆菌（Ｅ．ｃｏｌｉ）中的表达．运用重组ＤＮＡ和聚合酶链反应（ＰＣＲ）等分子生物学技术,以表达Ｓｊ２６ＧＳＴ的Ｅ．ｃｏｌｉｐＧＥＸ衍生质粒为模板,经ＰＣＲ得到编码Ｓｊ２６ＧＳＴ的全长ｃＤＮＡ片段．将其按正确的阅读框顺序,克隆到人结核杆菌热休克蛋白（ｈｅａｔｓｈｏｃｋｐｒｏｔｅｉｎ,ＨＳＰ）７０的启动子下游,再将ＨＳＰ７０启动子和Ｓｊ２６ＧＳＴ基因一起亚克隆到Ｅ．ｃｏｌｉ－分枝杆菌穿梭质粒ｐＢＣＧ－２０００中,得到Ｅ．ｃｏｌｉ－分枝杆菌穿梭表达质粒ｐＢＣＧ－Ｓｊ２６．ｐＢＣＧ－Ｓｊ２６电转化入ＢＣＧ和Ｍ．ｓｍｅｇｍａｔｉｓｍｃ２１５５中表达Ｓｊ２６ＧＳＴ抗原,所表达的天然重组Ｓｊ２６ＧＳＴ（ｒＳｊ２６ＧＳＴ）为可溶性蛋白,在ＳＤＳ－ＰＡＧＥ上分子量为２６ｋＤ处可见明显的表达蛋白带．其表达量分别占ＢＣＧ和Ｍ．ｓｍｅｇｍａｔｉｓ菌体总蛋白的１５％和１０％．可见,Ｓｊ２６ＧＳＴ基因能在ＢＣＧ中高效表达．     

GSTs同工酶基因在乳腺癌中的扩增与基因的表达

采用ＤＮＡ和ＲＮＡ的斑点杂交分析方法,对３２例乳腺癌和相应的癌旁正常组织中ＧＳＴ－π、ＧＳＴ－α和ＧＳＴ－μ基因的ＤＮＡ扩增和ＲＮＡ转录表达情况进行研究,发现ＧＳＴ－π在乳腺癌中存在基因扩增和明显的ｍＲＮＡ表达升高,ＧＳＴ－π基因表达调控主要在转录水平进行的;ＧＳＴ－α和ＧＳＴ－μ在乳腺癌中表达水平较低,但仍可见α和μ类ＧＳＴ同工酶ｍＲＮＡ转录在肿瘤和正常组织中发生了较大的变化。结合乳腺癌中雌激素受体（ＥＲ）表达情况还发现ＧＳＴ－π表达水平与ＥＲ的表达存在负相关性。     

抗癌胚抗原单链抗体基因的构建及高效表达

采用重组ＰＣＲ技术将已获得的抗癌胚抗原鼠源单克隆抗体Ｅ７Ｂ１０重,轻链可变区基因经（Ｇｌｙ３Ｓｅｒ）３编码的寡核苷酸拼接成单链抗体基因,并在大肠杆菌中高效表达了单链抗体Ｃ端的融合蛋白,其表达量达到菌体总蛋白的２０％,ＳＤＳ－ＰＡＧＥ和Ｗｅｓｔｅｒｎ印迹图谱显示表达产物分子量为２７ｋＤ,与其基因编码蛋白的理论推算值相符。     

生物信息学技术克隆人类神经髓鞘蛋白零家族基因

为克隆新的髓鞘蛋白相关基因,将ＭＰＺ基因编码区ｃＤＮＡ与ＥＳＴ数据库进行同源性比较,得到与ＭＰＺ显著相似的２个ＥＳＴ,构建成８０１ｂｐ的重叠群。此重叠群与定位在１ｑ２４的１２８ｋｂ ｇＤｎＡ的相似性为１００％。计算机分析有ｂｐ和重叠群可能存在一个４３５ｂｐ的阅读框架。在重叠群上设计两个引物与文库载体臂上的引物配对,扩增各种ｃＤＮＡ文库ＤＮＡ作巢式ＰＣ拓所得ｃＤＮＡ上再设计引物进行巢式ＰＣＲ,最终克     

心脏特异表达基因ASBIO的克隆及表达

从人类心脏文库中成功克隆了一个新的含有锚蛋白重复序列及SOCS盒结构域蛋白（ Ankyrin repeat and SOCS box protein, ASB）的家族成员ASBIO。该基因定位于染色体7q36．1,开放阅读框包含1329个核苷酸,由7个锚蛋白重复序列和1个SOCS盒组成,编码452个氨基酸,分子量大约是49．5kD。物种间的进化型分析比较表明该基因是非常保守的,人的ASB10基因和小鼠的Asb10基因有84．8％的同源性。半定量RT-PCR实验结果证明Asb10基因在成年小鼠的心脏和肌肉组织中高表达,提示其可能与心脏和肌肉组织的发育有关。亚细胞定位显示ASB10蛋白在细胞质和细胞核均有表达,为进一步研究奠定了基础。     

人类新基因ANKZF1的克隆与表达研究

心脏发育是一个非常复杂的过程,受一系列基因的精确调控.研究表明,许多锌指蛋白参与心脏的形成和疾病的发生.为了鉴定新的与心脏发育有关的人类锌指基因,运用同源基因克隆法,通过PCR技术扩增获得一个新的人类基因,其cDNA全长2459bp,其编码的蛋白由342个氨基酸残基组成(相对分子质量约为7.45kD).经国际人类基因命名委员会批准被命名为ANKZF1.该基因是哺乳动物物种特有基因.利用RTP-CR技术分析表明,该基因在胚胎的心脏、胃、肾和脑组织中有特异性的表达,提示该基因可能与心脏等组织的发育有关.     

苋菜凝集素基因的克隆及在转基因烟草中抗蚜性研究

通过ＰＣＲ从苋属植物千穗谷（Ａmaranthus hypochondriacus)的总ＤＮＡ中扩增出苋菜凝集素（ＡＨＡ）的核基因片段。序列分析结果表明该基因为２４５３bp,含有－１５３８bp的内含子和两个分别为２１２bp和７０３bp的外显子。采取反向ＰＣＲ的方法获得仅含该基因的编码区克隆。以此为基础与二元表达载体pBin438构建含内含子与不含内含子ＡＨＡ基因的植物表达载体pBAHAg和pBAHAc并通过土壤农杆菌介导转了化烟草,转化再生植株的ＰＣＲ和Southern blot分析表明,ＡＨＡ基因已整合到烟草的染色体中,有单贝和多拷贝的整合。用与ＡＨＡ蛋白高度同源的ＡＣＡ蛋白的抗血清进行了免疫斑点（Immunodot blot)检测,结果初步表明转基因烟草有ＡＨＡ蛋白的表达,虫试结果表明转pBAHAg和pBAHAc烟草对蚜虫的平均抑制率分别达５７．２％和４８．８％,有的高达９０％以上,含内含子和不含内含子的ＡＨＡ基因在转基因植株中的抗蚜性不同。     

水稻蜡质基因5‘非翻译区一个与调控有关的内含子

从发育的水稻种子中分离出ＲＮＡ,经ＲＴ－ＰＣＲ反应并结合顺序测定,在籼稻２３２蜡质基因编码区５‘上游非翻译区中证明确实存在一个长度为１１２６ｂｐ的内含子,其Ａ＋Ｔ碱基的含量高达６７．４％,它的边界符合真核基因内含子的ＧＴ－ＡＧ规则。表明该内含子与蜡质基因的表达调控有一定的关系。     

人产肠毒素大杆菌ST,LT—B肠毒素基因融合的研究

将人产肠毒素大肠杆菌,编码耐热肠毒素的基因片段与编码不耐热肠毒素Ｂ亚基的基因进行融合,并在此基础上进行了不同数目ＳＴ基因的串联,ＥＬＩＳＡ检测融合基因表达蛋白产物观察到ＳＴ与ＬＴ－Ｂ之间存在着相互影响。     

Recent advances in the study of Kaposi's sarcoma-associated herpesvirus replication and pathogenesis

It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.     

A Unique Protease Cleavage Site Predicted in the Spike Protein of the Novel Pneumonia Coronavirus (2019-nCoV) Potentially Related to Viral Transmissibility

正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases     

Curcuminoids as inhibitors of thioredoxin reductase: A receptor based pharmacophore study with distance mapping of the active site

Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.     

The structure, reproduction and taxonomy of Vidalia and Osmundaria (Rhodophyta, Rhodomelaceae)

Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.     

New or rare chromosome counts in Artemisia L. (Asteraceae, Anthemideae) and related genera from Kazakhstan

Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.