HCV NS5A基因表达及其在血清学检测中的应用评估

人丙型肝炎病毒 (ＨＣＶ)感染可引起丙型肝炎、肝硬化和肝细胞癌[1] 。丙型肝炎病毒是单股正链ＲＮＡ病毒 ,基因组约长 9.5ｋｂ ,仅有一个开放阅读框 ,编码一个大的聚蛋白前体 ,由宿主蛋白酶和病毒编码的蛋白酶加工成多个成熟蛋白。非结构蛋白ＮＳ5Ａ分子量为 56ｋＤ/ 58ｋＤ。目前对ＮＳ5Ａ蛋白的功能尚不清楚 ,ＮＳ5Ａ蛋白可降低干扰素治疗效果[2 ] ;ＮＳ5Ａ蛋白含核定位序列 ,因此人们推测它在ＨＣＶＲＮＡ复制过程中可能起一定的作用[3～ 4 ] 。本研究在大肠杆菌中表达全长ＮＳ5Ａ蛋白 ,提纯后ＮＳ5Ａ蛋白能与大多数丙肝阳性血清起强烈…     

丙型肝炎病毒基因组的翻译及其产物的加工

丙型肝炎病毒（ＨＣＶ）是一种单正链ＲＮＡ病毒,其５’非编码区（５’ＮＣＲ）是决定病毒蛋白表达的关键区。基因突变与报道基因表达技术研究表明５’ＮＣＲ有一内部核糖体进入位点（ＩＲＥＳ）。类似于微小ＲＮＡ病毒属。ＨＣＶＲＮＡ翻译成为一条多蛋白分子,对蛋白酶的裂解加工后形成１０余种结构和非结构蛋白。研究ＨＣＶＲＮＡ的翻译及产物加工,对ＨＣＶ及其抗原表达载体有重要意义。     

牛奶子的组织培养及植株再生

1　植物名称　牛奶子 (Ｅｌａｅａｇｎｕｓｕｍｂｅｌｌａｔａ) ,又称甜枣、羊奶子。2　材料类别　幼苗的下胚轴。3　培养条件　 ( 1 )ＭＳ 6 ＢＡ 1ｍｇ·Ｌ- 1 (单位下同 ) 2 ,4 Ｄ 3 ＩＡＡ 0 .5 ＣＨ 30 0 ;( 2 )ＭＳ 6 ＢＡ2 2 ,4 Ｄ 2 ＮＡＡ 0 .5 ＣＨ 30 0 ;( 3)ＭＳ 6 ＢＡ3 2 .4 Ｄ 1 ＩＢＡ 0 .5 ＣＨ 30 0 ;( 4 )ＭＳ 6 ＢＡ1 .5 ＩＡＡ 0 .5;( 5)ＭＳ 6 ＢＡ 1 .5 ＮＡＡ 0 .5;( 6)ＭＳ 6 ＢＡ 1 .5 ＩＢＡ 0 .5;( 7)ＭＳ 6 ＢＡ 0 .2 ＩＡＡ 0 .5 ＧＡ 0 .5;( 8)ＭＳ 6 ＢＡ 0 .2 ＩＡＡ 0 .1 ＧＡ…     

不同株的熊蜂短膜虫与宿主生存的关系

ＴＨＥＲＥＬＡＴＩＯＮＳＨＩＰＢＥＴＷＥＥＮＤＩＦＦＥＲＥＮＴＳＴＲＡＩＮＳＯＦＣＲＩＴＨＩＤＩＡＢＯＭＢＩＡＮＤＴＨＥＳＵＲＶＩＶＡＬＯＦＴＨＥＩＲＨＯＳＴＢＵＭＢＬＥＢＥＥＳ不同株的熊蜂短膜虫与宿主生存的关系ＫｅｙｗｏｒｄｓＣｒｉｔｈｉｄｉａｂｏ...     

水稻草矮病毒核衣壳蛋白基因克隆及在大肠杆菌中的表达

水稻草状矮化病于70年代曾在南亚、东南亚大面积发生,给当地的水稻生产造成严重损失,在我国也有分布[1]。其病原是水稻草矮病毒(Ｒｉｃｅｇｒａｓｓｙｓｔｕｎｔｖｉｒｕｓ,ＲＧＳＶ),为纤细病毒属(Ｔｅｎｕｉｖｉｒｕｓ)的一个成员,病毒粒体丝状,由核衣壳蛋白和基因组ＲＮＡ组成[2]。基因组含六个ｓｓＲＮＡ片段,均为双义编码[3,4],其中ＲＮＡ5的毒义互补链编码核衣壳蛋白(ｎｕｃｌｅｏｃａｐｓｉｄｐｒｏｔｅｉｎ,ＮＣＰ)[3]。本文报道应用ＲＴＰＣＲ技术获得ＲＧＳＶ沙县分离株(ＲＧＳＶＳＸ)ＮＣＰ基因的ｃＤＮＡ克隆,并得到其在大肠杆…     

丙型肝炎病毒丝氨酸蛋白酶的研究进展

丙型肝炎病毒（ＨＣＶ）非结构３区（ＮＳ３）编码的丝氨酸蛋白酶是ＨＣＶ复制过程中的重要蛋白酶,负责对ＮＳ３、ＮＳ４及ＮＳ５进行加工。ＮＳ４ａ是ＨＣＶ丝氨酸蛋白酶作用的辅因子,并具有多种活性。ＨＣＶ丝氨酸蛋白酶有相对特异的底物,其活性不能被一般的丝氨酸蛋白抑制剂所抑制。丝氨酸蛋白酶是ＨＣＶ药物设计的靶目标之一。对其结构与功能的研究有着重要意义。     

水母雪莲的幼根培养及植株再生

1　植物名称　水母雪莲 (Ｓａｕｓｓｕｒｅａｍｅｄｕｓａ) ,藏药中称为恰羔素巴。2　材料类别　无菌苗的根。3　培养条件　诱导愈伤组织培养基以ＭＳ、Ｃ1 7或Ｗ 1 4为基本培养基 ,附加 2 ,4 Ｄ 1～ 2ｍｇ·Ｌ- 1 (单位下同 ) 肌醇 2 0 0 蔗糖 3% 琼脂 0 .5%。继代培养基为ＭＳ 2 ,4 Ｄ 1 肌醇 2 0 0 ＣＨ 30 0 蔗糖 3%～ 5% 琼脂 0 .5%。分化培养基配方为 1 /2ＭＳ ＫＴ 1 ＣＨ 30 0 肌醇 2 0 0 蔗糖 3% 琼脂0 .5% ,再附加 ( 1 )ＮＡＡ 0 .5 6 ＢＡ 1或 ( 2 )ＮＡＡ1 6 ＢＡ 2。所用培养基的 ｐＨ均调为 5.8。培养温度为…     

ACTA BIOCHI MICA et BIOPHYSICA SINICA Author Index for(2002) Vol.34,No.1—6

ＡｕｔｈｏｒｓＮｏ . ＰａｇｅＡＮＬｉ Ｊｉａ 1 10ＡＯＳｈｉ Ｚｈｏｕ 2 192ＡＯＳｈｉ Ｚｈｏｕ 4 43 8ＢＡＩＣｈｅｎ 5 618ＢＡＩＣｈｅｎ 6 685Ｂ¨ＯＩＮＧＳｅｂａｓｔｉａｎ 3 2 73ＣＡＩＣｈｕｎ 2 14 3ＣＡＩＪｉｎ 4 45 6ＣＡＩＳｈａｏ Ｘｉ 6 75 2ＣＡＩＷｅｉ Ｍｉｎ 1 98ＣＡＩＷｅｉ Ｍｉｎ 2 2 3 0ＣＡＩＹｏｕ Ｍｉｎ 3 3 17ＣＡＯＦａｎｇ 3 3 0 4ＣＡＯＪｉｅ 3 3 46ＣＡＯＫａｉ Ｍｉｎｇ 1 87ＣＡＯＹａ 1 16ＣＨＡＩＭｉｎ Ｑｉａｎｇ 3 3 10ＣＨＥＷｅｎ Ｌｉａｎｇ 2 2 0 3ＣＨＥＹａｎ Ｋｅ 4 5 0 5…     

转录因子YY1的作用机制

转录因子Ｙｉｎ Ｙａｎｇ 1 (ＹＹ1 ,又称ＮＦ Ｅ1、δ、ＵＣＲＢＰ、ＣＦ1 )是锌指类转录因子ＧＬ1 Ｋｒ櫣ｐｐｌ家族中的一员 ,广泛地存在于人、鼠、非洲爪蟾中[1、2 ] 。ＹＹ1蛋白含有 41 4个氨基酸残基 ,分子量为 6 5ｋＤ。在靠近Ｎ 末端处有一个酸性区域 ,紧接着是连续 1 2个组氨酸的序列和一段富含Ｇｌｙ和Ａｌａ的区域 ,在Ｃ 末端含有与ＲＥＸ 1蛋白相似序列的Ｃ2 Ｈ2 锌指结构。ＹＹ1因子最初是作为腺伴随病毒(ＡＡＶ)的Ｐ5 启动子和免疫球蛋白 (Ｉｇ)ｋ3′增强子的阻抑因子分离到的 ,后来又相继证实ｃ ｆｏｓ、ｃ ｍｙｃ、ｓｕｒ…     

不依赖甲硫氨酸的翻译起始

Ｓａｓａｋｉ等在ＰｒｏｃＮａｔｌＡｃａｄＳｃｉＵＳＡ 2 0 0 0年第 4期上报道了一种不依赖甲硫氨酸的翻译起始方式[1] 。ＰＳＩＶ (Ｐｌａｕｔｉａｓｔａｌｉｉｎｔｅｓｔｉｎｅｖｉｒｕｓ)是一种昆虫ＲＮＡ病毒 ,属蟋蟀麻痹样病毒组 (Ｃｒｉｃｋｅｔｐａｒａｌｙｓｉｓ ｌｉｋｅｖｉｒｕｓｅｓ) ,为正链ＲＮＡ病毒。属于该组的还有ＤＣＶ、ＲｈＰＶ、ＨｉＰＶ等。该组病毒的理化性质与哺乳动物的小ＲＮＡ病毒 (ｐｉｃｏｒｎａｖｉｒｕｓ)相似 ,但基因图 1　 (Ａ)ＰＳＩＶ基因组结构 ;(Ｂ)预测的外壳蛋白编码区上游的茎环结构组织不同。…     

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.     

Comparative morphology of the carpel in the Liliaceae: Hewardieae, Petrosavieae, and Tricyrteae

The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle.     

Selection with two alleles and complete dominance

For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.     

Composition and diversity of bird communities in Swedish farmland–forest mosaic landscapes

CapsuleThe amount of forest (at local and landscape scales) and occurrence of residual habitats at the local scale are shown to be the major factors influencing bird community composition in farmland–forest landscapes in central Sweden.

Aims To investigate the importance of local habitat and landscape structure for breeding birds in farmland–forest landscapes in central Sweden.

Methods Breeding birds were censused at 292 points. A detailed habitat mapping was made within 300 m of the points. Within a 300–600 m radius only two major habitats (forests and arable fields) were identified.

Results Cluster analyses of bird communities identified three site types that also differed in habitat composition: (i) partially forested sites in forested landscapes; (ii) heterogeneous sites with residual habitats in mosaic landscapes; and (iii) field-dominated farmland sites in open landscapes. A total of 19 of 25 farmland bird species (restricted to farmland or using both farmland and forest) had the highest abundance in farmland sites with mosaics of forest and farmland, while only six farmland species had the highest abundance in field-dominated sites. The bird community changed from being dominated by farmland species to being dominated by forest species (common in forest landscapes without farmland) at small proportions (10–20%) of forest at the local scale. A major difference in habitat composition between heterogeneous and field-dominated sites was the occurrence of different residual habitats (e.g. shrubby areas and seminatural grasslands). These habitats seemed to influence bird community composition more than land-use, despite covering <10% of the area. Seminatural grasslands were important for bird community composition and species-richness, but grazing seemed to be less important. Among different land-use types, cereal crops were the least preferred fields. Set-asides with tall vegetation and short rotation coppices were positively associated with species-richness of farmland birds.

Conclusion In general, the composition of the landscape was important for bird community composition, although amount and distribution of forests, occurrence of residual habitats and land-use of fields at the local scale had the strongest influence on bird community composition. The possible implications of these patterns for managing farmland–forest landscapes are discussed.     

Chemical constituents from the fruits of Rhus typhina L. and their chemotaxonomic significance

This work describes the isolation and characterization of twenty-nine compounds from the fruits of Rhus typhina L., including eleven flavonoids (1–11), eleven phenols (12–22), two pentacyclic triterpenes (23–24), two organic acids (25–26), one lumichrome (27), one courmarin (28) and one pyrimidine (29) on the basis of their spectroscopic data. Compounds apigenin (1), daidzein (4), orobol (5), 3′, 5, 5′, 7-tetrahydroxyflavanone (6), naringenin (7), butein (8), (-)-catechin (9), quercetin-3-O-α-L-(3″-O-galloyl)-rhamnoside (11), 2-hydroxybenzoic acid (13), 4-hydroxybenzaldehyde (14), vanillin (15), methyl 3,4-dihydroxybenzoate (16), 3,5-dihydroxybenzamide (18), tyrosol (19), caffeic acid (20), 3-(2,4,6-trihydroxyphenyl)-1-(4-hydroxyphenyl)-propan-1-one (21), phlorizin (22), friedelin (23), oleanolic acid (24), 4,4-dimethyl-heptanedioic acid (25), anthranilic acid (26), lumichrome (27), scoparone (28) and uracil (29) have not been recorded before in this plant. This is the first report on the occurrence of compounds 4–7, 9, 11, 13–14, 16, 18–21, 25–29 from the genus Rhus. Moreover, the chemotaxonomic significance of these isolated compounds was also summarized.