光遗传学技术在神经生物学领域的发展及应用

光遗传学技术是基因工程学与光学相结合的一项新兴技术。简要介绍了光遗传学技术的概念、发展过程及作用机理,概述了光遗传学技术中通道视蛋白的类型和该技术在神经生物学领域的应用。     

光遗传学

虽然＂光遗传学＂只是一种技术方法,但它在文献中正愈来愈多地被提到。光遗传学结合了重组DNA技术与光学技术,对细胞生物学的研究非常有用。它被广泛应用于活细胞内目标蛋白质的跟踪以及选择性地控制脑中某类细胞的特定的神经活动从而推动了神经科学研究的深入。近来光遗传学的应用扩展到了信号转导的研究,也开始有医学临床的应用的报道。进一步发展光遗传学无疑将推动合成生理学的研究。光遗传学被《自然-方法学》期刊评为2010年年度方法。     

《Molecular Plant》文章中文摘要

题目：从LoV到BLUF——黄素蛋白对光遗传学工具的贡献（综述） 摘要：光遗传学是结合光学和遗传学研究方法的新型学科领域,通过非侵害性干扰对细胞活动进行精确的时空控制。虽然这一领域最初是由神经科学发展而来,光遗传学广泛的应用于多种不同生物系统的研究中,其应用的广度随着技术的进步而不断得到拓宽。另外,     

利用光遗传学研究抑郁行为神经机制的新进展

光遗传学技术是将光学、遗传学和分子生物学结合而产生的一门新技术。此项技术凭借能高度精确地改变清醒的、可自由活动的动物脑内靶神经元功能状态的优势,有望成为抑郁行为神经机制研究的理想手段。本文在简介光遗传学技术及其优越性的前提下,对该技术在抑郁行为神经机制研究中的应用进展做一综述。     

光遗传学及其在神经科学方面的应用与进展

光遗传学是一种通过向哺乳动物的神经细胞转染微生物视蛋白基因,使其可以对光照产生应答从而调节神经元活性的技术。该技术在研究中具有显著优势,但同时也存在诸多局限。近年来,有关光遗传学的研究数量迅猛增长,该技术也使多个研究方向实现了重大突破,其中包括对神经系统和视觉通路,以及多种疾病治疗方法的研究。从光遗传学技术的发明和作用机理引入,综述并讨论其在神经科学方面的应用与进展。     

光声成像及其在生物医学中的应用

光声成像是一种新近迅速发展起来、基于生物组织内部光学吸收差异、以超声作媒介的无损生物光子成像方法,它结合了纯光学成像的高对比度特性和纯超声成像的高穿透深度特性的优点,以超声探测器探测光声波代替光学成像中的光子检测,从原理上避开了光学散射的影响,可以提供高对比度和高分辨率的组织影像,为研究生物组织的结构形态、生理特征、代谢功能、病理特征等提供了重要手段,在生物医学临床诊断以及在体组织结构和功能成像领域具有广泛的应用前景.对光声成像技术的机理、光声成像技术和方法、光声图像重建算法以及光声成像在生物医学上的应用情况作一个简单介绍,希望有助于推动我国在该领域的科研和开发应用工作的迅速发展.     

光学技术在早期龋齿检测中的应用

介绍了光学技术在口腔医学早期龋齿无损检测领域的应用,包括基于牙齿自体荧光效应的定量光导荧光技术和激光龋齿检测技术;基于光散射效应的数字化显影光纤透照术,以及基于牙釉质双折射效应的偏振敏感光学相干断层术和偏振拉曼光谱技术.详细介绍了各种光学方法应用于龋齿检测的基本原理、实验方案和研究现状,并对不同的光学方法进行比较.最后,提出基于频域荧光寿命成像的早期龋齿检测方法,并对该方案的技术路线进行了介绍.     

感光色素蛋白与视网膜退行性疾病

随着多种治疗视网膜退行性疾病的手段的开发,感光色素蛋白逐渐显现出独特的优势。近年来,各种针对视觉传导神经环路的不同环节的感光色素蛋白干预手段陆续出现,本文结合感光色素蛋白在视力恢复中的研究进展,介绍光遗传学在视网膜退行性疾病治疗中的应用,而光遗传学研究的核心工具是感光色素蛋白。因此本文将重点围绕感光色素蛋白的改进展开介绍。     

光遗传学工具的开发及其应用研究

细胞所处微环境的动态变化对细胞分化、细胞信号通路、个体生长以及疾病等有很大影响。光遗传学技术利用基因编码蛋白质表达并结合光控的手段为动态调控细胞信号通路、细胞定位和基因表达等方面提供了一种全新、无损、可逆、非侵入、时空特异性的研究手段。文中总结了光遗传学元件的类型以及涉及的细胞信号通路,并探讨了光控细胞信号通路的应用与未来发展前景。     

光遗传学技术在调控细菌生命活动中的应用

光遗传学技术利用光作为输入信号,能够精准地调控细胞的生理功能,同时具有高度的时间和空间特异性,使得构建高度动态的调控系统成为可能.近年来,随着新型光敏蛋白的发现和光照系统的创新,基于光遗传学技术的光控系统的效率得到了显著提高.通过合成生物学方法构造各种生物回路,光控系统在细菌中的应用也日益广泛.将光控系统作为输入模块,与其他生物功能模块相结合,能够实现对基因表达、蛋白质活性以及细菌生理功能的调控.本文主要介绍光遗传学技术的基本原理及其在合成生物学和调控细菌生命活动方面的应用.     

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.