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。...     

DNA损伤与修复

《ＤＮＡ损伤与修复,（第２卷）：高级真核生物的ＤＮＡ修复》（ＤＮＡＤａｍａｇｅａｎｄＲｅｐａｉｒ,ＶｏｌｕｍｅＩＩ：ＤＮＡＲｅｐａｉｒｉｎＨｉｇｈｅｒＥｕｋａｒｙｏｔｅｓ）由ＪａｃＡ．Ｎｉｃｋｏｌｏｆｆ和ＭｅｒｌＦ．Ｈｏｅｋｓｔｒａ编著,１９９８年ＨｕｍａｎａＰｒｅｓｓ出版,６３９页。ＤＮＡ损伤与修复提供了在广泛多样化生物体范围内ＤＮＡ修复主要方面的重要和简洁评论。第２卷：高级真核生物的ＤＮＡ修复集中于哺乳动物系统、人体遗传学疾病和癌症,强调最近５年发展的重要过程。主要题目：紫外线和Ｘ线的修复,…     

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.     

Enterovirus 71 3C proteolytically processes the histone H3 N-terminal tail during infection

Highlights
1. The N-terminal tail of histone H3 is specifically cleaved during EV71 infection.
2. Viral protease 3C is identified as a protease responsible for proteolytically processing the N-terminal H3 tail.
3. Our finding reveals a new epigenetic regulatory mechanism for Enterovirus 71 in virus-host interactions.     

Detection of EBV and HHV6 in the Brain Tissue of Patients with Rasmussen’s Encephalitis

Rasmussen’s encephalitis (RE) is a rare pediatric neurological disorder, and the exact etiology is not clear. Viral infection may be involved in the pathogenesis of RE, but conflicting results have reported. In this study, we evaluated the expression of both Epstein-Barr virus (EBV) and human herpes virus (HHV) 6 antigens in brain sections from 30 patients with RE and 16 control individuals by immunohistochemistry. In the RE group, EBV and HHV6 antigens were detected in 56.7% (17/30) and 50% (15/30) of individuals, respectively. In contrast, no detectable EBV and HHV6 antigen expression was found in brain tissues of the control group. The co-expression of EBV and HHV6 was detected in 20.0% (6/30) of individuals. In particular, a 4-year-old boy had a typical clinical course, including a medical history of viral encephalitis, intractable epilepsy, and hemispheric atrophy. The co-expression of EBV and HHV6 was detected in neurons and astrocytes in the brain tissue, accompanied by a high frequency of CD8⁺ T cells. Our results suggest that EBV and HHV6 infection and the activation of CD8⁺ T cells are involved in the pathogenesis of RE.     

Perinatal Vertical Transmission of Chikungunya Virus in Ruili,a Town on the Border between China and Myanmar

正Dear Editor,Chikungunya virus (CHIKV), an arbovirus in the family of Togaviridae, genus Alphavirus, is transmitted by the A.aegyptii or A. albopictus mosquito, and causes disease in humans characterized by fever, rash, and arthralgia (Silva and Dermody 2017; Suhrbier 2019). It was first reported in 1953 in Tanzania, and caused only a few outbreaks and sporadic cases in Africa and Asia in last century. However, in the epidemic in 2004, CHIKV acquired mutations that conferred enhanced transmission by the A. albopictus mosquito(Schuffenecker et al. 2006). Since then, it has successively caused outbreaks in Africa, the Indian Ocean, South East Asia, the South America, and Europe (Zeller et al. 2016).     

Development of a Novel Reverse Transcription Loop-Mediated Isothermal Amplification Method for Rapid Detection of SARS-CoV-2

In conclusion, the novel visual RT-LAMP assay is a simple, rapid, and sensitive approach for detection of SARS-CoV-2, and it is ready for application in primary care and community hospitals or health care centers, and even patients' own houses in response to the current SARS-CoV-2 epidemic because the assay does not require sophisticated equipment and skilled personnel. Furthermore, it is also ready to be used in fields for screening samples from wild animals and environments to facilitate the identification of potential intermediate hosts that mediate the cross-species transmission of SARS-CoV-2 from bats to humans.