真核生物DNA的进化

真核生物ＤＮＡ的进化刘振山（河北省张家口市教委科学研究室０７５０３１）生物在进化过程中的演变都是由ＤＮＡ的自发改变开始的,当生物从简单形式进化到较复杂的形式后,基因组无论是在遗传物质ＤＮＡ的含量上,还是在基因的数目上都有所扩大,遗传物质的这种量和质的...     

真核生物转录因子对DNA序列的识别

真核生物转录因子对ＤＮＡ序列的识别杨岐生（浙江大学生物科学与技术系,杭州３１００２７）关键词真核生物转录因子,蛋白质－ＤＮＡ识别研究蛋白质和ＤＮＡ两类生物大分子的相互作用,以阐明基因表达、调控及信息传递的分子机制,是认识生命活动本质的核心问题。本文介...     

线粒体DNA聚合酶的起源研究

随着新的DNA聚合酶A家族成员的加入,家族内部的系统发育关系需要重新检查。分析显示：在真核生物演化的不同阶段,线粒体DNA聚合酶基因可能通过水平基因转移方式起源于不同类群的生物。原始真核生物线粒体DNA聚合酶基因可能来源于细菌,植物线粒体DNA聚合酶基因可能从质粒获得,而真菌和动物线粒体DNA聚合酶基因可能起源于T3/T7相关噬菌体。     

端粒与端粒酶

端粒与端粒酶任波（湖北医学院生物教研室武汉４３００７１）染色体在细胞世代中保持其稳定性应起码具备３个结构要素,即ＤＮＡ复制起点,着丝粒以及端粒（ｔｄｏｍｅｒｅ）。端粒是真核生物染色体末端的特殊结构,由蛋白质与ＤＮＡ构成。其中的ＤＮＡ在结构与功能上与其...     

线粒体DNA聚合酶的起源与演化

随着新的DNA聚合酶A家族成员的加入,家族内部的系统发育关系需要重新检查,来自大肠杆菌DNA聚合酶I(DNA Pol I)和它的细菌、噬菌体和真核细胞同源物被用来重建这个家族的系统发育史.分析显示:在真核生物演化的不同阶段,线粒体DNA聚合酶基因可能通过水平基因转移方式起源于不同类群的生物.原始真核生物线粒体DNA聚合酶基因可能来源于细菌,植物线粒体DNA聚合酶基因可能从质粒获得,而真菌和动物线粒体DNA聚合酶基因可能起源于T3/T7相关噬菌体.     

线粒体DNA病

线粒体ＤＮＡ病王学敏杨雨善谢惠君郑惠民（第二军医大学,上海２００４３３）关键词线粒体病线粒体ＤＮＡ近年确认了线粒体ＤＮＡ（ｍｔＤＮＡ）突变会引起人类疾病,临床症状有盲、聋、痴呆、运动障碍、肌肉衰弱、心力衰竭、糖尿病、肾功能不全、肝病等。ｍｔＤＮＡ呈裸...     

用人胞质体对线粒体疾病进行基因治疗

用人胞质体对线粒体疾病进行基因治疗关键词胞质体线粒体ＤＮＡ基因治疗１．引言线粒体ＤＮＡ（ｍｔＤＮＡ）的突变能引起罕见的线粒体脑性肌病和常见的心血管疾病、糖尿病等退行性疾病。由于线粒体疾病的根本原因为ｍｔＤＮＡ的突变及其蓄积,因此,治疗线粒体疾病的根本...     

自私DNA及其功能

自私ＤＮＡ及其功能李子银,胡会庆（华中农业大学农学系,武汉４３００７０）真核生物基因组的一个显著特点就是含有大量的非编码序列,这些ＤＮＡ序列包括高度重复序列,特别是占总ＤＮＡ１—３０％的卫星ＤＮＡ（ＳａｔｅｌｌｉｔｅＤＮＡ）;中度重复序列（如哺乳动物...     

线粒体DNA结构改变与人类疾病

线粒体ＤＮＡ结构改变与人类疾病冯昌全（四川省岳池县教研室６３８３５０）何青平（四川省岳池县人民医院６３８３３５０）人体细胞的细胞核中ＤＮＡ的分子结构发生改变。人会患遗传疾病。人体细胞中线粒体ＤＮＡ（ｍｔＤＮＡ）的分子结构发生改变,也会引起人患遗传病。...     

细菌能进行有氧呼吸吗?

答:细菌能进行有氧呼吸,细菌的有氧呼吸与真核生物的有氧呼吸基本相同,所不同的是细菌的呼吸链位于细胞膜上,因而细菌的有氧呼吸在细胞膜中进行,而不象真核生物那样主要在线粒体中进行.     

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.     

Synthesis and antimicrobial studies of hydrazone derivatives of 4-[3-(2,4-difluorophenyl)-4-formyl-1H-pyrazol-1-yl]benzoic acid and 4-[3-(3,4-difluorophenyl)-4-formyl-1H-pyrazol-1-yl]benzoic acid

Microbial resistance to antibiotics is an unresolved global concern, which needs urgent and coordinated action. One of the guidelines of the Centers for Disease Control and Preventions (CDC) to combat antibiotic resistance is the development of new antibiotics to treat drug-resistant bacteria. In our effort to find new antibiotics, we report the synthesis and antimicrobial studies of 30 new pyrazole derivatives. These novel molecules have been synthesized by using readily available starting materials and benign reaction conditions. Some of these molecules have shown activity with MIC values as low as 0.78?µg/mL against four bacterial strains; Staphylococcus aureus, methicillin-resistant S. aureus, Bacillus subtilis, and Acinetobacter baumannii. Furthermore, active molecules are non-toxic to mammalian cell line.

     

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.     

Novel compounds with potent CDK9 inhibitory activity for the treatment of myeloma

Cyclin-dependent kinases (CDKs) and Polo-like kinases (PLKs) play key role in the regulation of the cell cycle. The aim of our study was originally the further development of our recently discovered polo-like kinase 1 (PLK1) inhibitors. A series of new 2,4-disubstituted pyrimidine derivatives were synthesized around the original hit, but their PLK1 inhibitory activity was very poor. However the novel compounds showed nanomolar CDK9 inhibitory activity and very good antiproliferative effect on multiple myeloma cell lines (RPMI-8226).