环状RNA影响肝疾病的发生发展

环状RNA (circular RNA, circRNA)广泛存在于多种生物细胞中,是一类由3′末端和5′末端经反向剪接共价结合形成的RNA分子。circRNA具有保守性、结构稳定、组织细胞特异性表达等特征。它们具有调控基因转录、充当微RNA海绵、参与蛋白质翻译及充当蛋白质诱饵等重要生物学功能,可影响细胞的增殖、凋亡、周期、迁移、侵袭和上皮间质转化等过程。circRNA与病毒性肝炎、肝纤维化、肝细胞肝癌、脂肪性肝病等重要肝疾病的病理生理过程密切相关。鉴于肝疾病是我国最常见的一类重大疾病,本文总结了国内外关于circRNA影响肝疾病发生发展的机制,希望为预防、诊断和治疗肝疾病提供新思路。     

CircRNA肿瘤相关生物学功能的研究进展

环状RNA(circRNA)是一类具有环状结构的非编码RNA(noncoding RNAs, ncRNA),广泛存在于多种生物细胞中,具有结构稳定、序列保守及细胞或组织特异性表达等特征。已被证实circRNA在许多癌症中存在表达异常,参与了恶性肿瘤的发生发展。CircRNA在细胞中的分布与其功能发挥密切相关。研究表明,胞核分布的circRNA可以参与调节mRNA转录和表观遗传调控,胞质分布的circRNA具有充当"miRNA海绵"、与RNA结合蛋白结合、影响蛋白质翻译、编码蛋白质等功能。本文对circ RNA在肿瘤中发挥的相关生物学功能进行综述,以期为后续研究提供一定的理论依据。     

环状RNA的功能特性与胃癌的发生及诊断

环状RNA(circular RNA, circRNA)是一类具备环状闭合结构的内源性非编码RNA(nocoding RNA,ncRNA),主要由外显子和(或)内含子转录而成,具有组织和细胞表型特异性及稳定性,在生命活动中行使着重要的生物学功能,如circRNA可充当微小RNA(microRNA, miRNA)海绵以调控基因表达、与蛋白质相互作用、直接参与翻译过程、参与免疫反应、调控细胞功能、参与缺氧诱导肿瘤发生发展等功能。特别是参与肿瘤的发生发展使circRNA能成为肿瘤诊断及治疗的潜在靶点。本文将从circRNA的功能、参与胃癌的发生发展以及作为临床诊断标志物等展开综述。     

环状RNA及其作为疾病标志物的潜能

环状RNA（circular RNA, circRNA）是一种共价闭合环状结构的内源性非编码RNA分子,不具有5′端帽子和3′端poly(A)尾巴结构,具有广泛性、保守性、组织特异性以及稳定性等特性;根据序列来源的不同可分为3种类型：外显子circRNA、内含子circRNA、外显子-内含子circRNA;随着生物信息学的快速发展和高通量测序技术的不断革新,目前已经在真核细胞中发现大量内源性circRNA,主要分布于细胞质中,其独特的序列结构,使它具有microRNA海绵、调节选择性剪接或转录、与RNA结合蛋白结合、滚动翻译和衍生假基因等功能;它参与癌症、糖尿病、神经系统疾病和动脉粥样硬化等疾病发生、发展过程。众多研究显示circRNA会成为新型的疾病临床诊断标志物或人类疾病治疗的潜在靶点,该评述较为详细地从circRNA的形成、特性、生物学功能、研究方法、研究数据库以及和疾病的关系等方面来阐述circRNA的最新研究进展,方便研究人员进行circRNA研究。     

环状RNA在巨噬细胞中的作用

环状RNA(circular RNA, circRNA)是一类特殊的非编码RNA类型,在真核生物细胞和人体转录本中大量存在。circRNA是由前体信使RNA(pre-mRNA)反向剪接形成的共价闭合环状RNA分子,通过充当微核糖核酸(microRNA, miRNA)"海绵"、与蛋白质结合、参与基因转录调控和蛋白质翻译等发挥其生物学作用。随着对circRNA研究的日益增多,已有研究人员报道了circRNA在免疫细胞中的作用。现对circRNA的形成、分类、生物学特性、功能及其在巨噬细胞中的作用作一概述。     

环状RNA与人类疾病

环状RNA(circular RNAs, circRNAs)是一类广泛存在于各种生物细胞中具有调控基因表达功能的非编码RNA,具有结构稳定和组织特异性表达等特征. 有些circRNA分子富含微小RNA结合位点,可通过充当竞争性内源RNA的角色来发挥作用,如CDR1as对miR-7的海绵作用与肺癌、乳腺癌、胶质瘤及肌萎缩性脊髓侧索硬化等疾病发生相关. cANRIL可通过影响多梳家族参与动脉粥样硬化的发生. 大量circRNA的发现及其结构和功能的阐明不仅可以使我们更加深入地了解疾病的发生机制,而且为相关疾病的预防、诊断和治疗提供了新的方向.     

circRNA在病毒感染及相关疾病诊断中的研究进展

环状RNA(circular RNA,circRNA)是一种新型非编码RNA,由mRNA在转录后加工过程中反向剪接形成。不同于线性RNA,circRNA是以共价键连接形成的闭合环状结构,缺少5?末端帽子和3?末端poly(A)尾巴结构。circRNA可作为miRNA(microRNA)的分子海绵,也可在细胞发生过程中发挥多种功能。此外,circRNA在机体免疫调控过程中也扮演了重要角色,参与了多种疾病的发生发展,因此对circRNA的深入探索可为治疗人类疾病提供重要的理论依据。该文就circRNA的生物合成、分类和功能作综述,重点讨论circRNA对病毒感染的调控机制以及circRNA作为病毒检测标记物和药物靶点的研究进展,从而为病毒性疾病的诊断提供新的参考依据和方向。     

circRNA相关数据库及其应用

环状RNA(circular RNA, circRNA)是由真核生物中的前体mRNA反向剪接产生的环状内源性RNA分子,分布广泛、结构稳定、序列高度保守,具有细胞和组织特异性。circRNA以多种方式参与调控生物学过程以及疾病的发生发展。目前发现的功能模式包含竞争性内源性RNA作用、与蛋白质互作、翻译成蛋白质以及顺式调控亲本基因的转录等。随着circRNA的基本信息、功能分析和与人类疾病的关系等研究内容不断更新增加,急需对海量的信息进行整合分析,以及对相应细胞或组织来源的circRNA进行分类。本文从基本信息整合及分析、相关功能分析和与人类疾病的相关性等方面,对目前常用的circRNA数据库进行综述,以期为circRNA研究提供参考。     

环状RNA与病毒感染之间相互关系的研究进展

非编码RNA (non-coding RNA,ncRNA)是指一类不具有编码蛋白质功能的RNA,包括转运RNA (transfer RNA,tRNA)、核糖体RNA (ribosomal RNA,rRNA)、微小RNA (micro RNA,miRNA)、长链非编码RNA (long non-coding RNA,lncRNA)以及环状RNA(circular RNA,circRNA)等.近年来circRNA在癌症,肿瘤以及心脑血管疾病等多种疾病中被证实发挥重要作用,此外研究还发现宿主circRNA与病毒来源的cicrRNA均会参与到病毒感染进程,但其中circRNA发挥的功能还有待进一步研究,因此,该文综述了circRNA的发现、分类、主要功能以及宿主circRNA和病毒来源的circRNA与病毒感染之间相互关系的研究进展,将有助于理解circRNA与病毒感染之间的互作机制.     

环状RNA的研究进展

环状RNA(Circular RNA,circRNA)是一类具有闭合环状结构的内源性非编码RNA(noncodingRNA,ncRNA),主要由前体RNA(pre-mRNA)通过可变剪切加工产生,circRNA广泛存在于所有真核生物中,并且非常稳定。目前,circRNA的研究已经成为了RNA研究领域的新热点,研究发现circRNA在转录本中占有相当大的比例,有的表达丰度甚至显著高于其他转录本。同时,circRNA对基因的表达有重要调控作用,在生物的发育进程中发挥了重要的生物学功能,如充当miRNA海绵、作为内源性RNA以及生物标记物,在疾病的诊断与治疗中也发挥重要作用。研究发现circRNA在一些疾病的发生中扮演了重要角色,包括动脉硬化、神经系统紊乱、糖尿病和癌症的发生。综述了circRNA的研究进展,阐述了circRNA的研究历史、circRNA的特点、形成过程、表达情况、circRNA与疾病间的关系以及circRNA的功能,并讨论了circRNA的研究意义及存在的问题。     

环状RNA在胃癌与结直肠癌中的功能和作为临床标志物的潜力

环状RNA（circRNA）是一种广泛存在于生物体内的新型内源性RNA。CircRNA由RNA前体可变剪接产生,比线性RNA有更好的稳定性,是最近几年RNA领域的明星分子。CircRNA来源于内含子或外显子,可充当miRNA海绵或者结合蛋白质来参与基因表达调控,甚至已发现有circRNA能编码蛋白质。越来越多的研究表明,circRNA在肿瘤（如：食管癌、肝癌、胃癌、结直肠癌和膀胱癌等）的发生发展中发挥了重要作用。近年来,circRNA在胃癌、结直肠癌的研究逐渐增加,circRNA可能成为新的生物学标志物发挥诊断和预后的作用。本文将主要介绍circRNA 在胃癌及结直肠癌的功能和作为临床标志物的研究进展。     

Circular RNA in cardiovascular disease: Expression,mechanisms and clinical prospects

Circular RNAs (circRNAs) are a group of covalently closed, endogenous, non-coding RNAs, which exist widely in human tissues including the heart. Increasing evidence has shown that cardiac circRNAs play crucial regulatory roles in cardiovascular diseases (CVDs). In this review, we aimed to provide a systemic understanding of circRNAs with a special emphasis on the cardiovascular system. We have summarized the current research on the classification, biogenesis and properties of circRNAs as well as their participation in the pathogenesis of CVDs. CircRNAs are conserved, stable and have specific spatiotemporal expression; thus, they have been accepted as a potential diagnostic marker or an incremental prognostic biomarker for CVDs.     

The expanding role of CDR1‐AS in the regulation and development of cancer and human diseases

CircRNAs are a superabundant and highly conserved group of noncoding RNAs (ncRNAs) that are characterized by their high stability and integrity compared with linear forms of ncRNAs. Recently, their critical role in gene expression regulation has been shown; thus, it is not far‐fetched to believe that their abnormal expression can be a cause of different kinds of diseases such as cancer, neurodegenerative, and autoimmune diseases. They can have a function in variety of biological processes such as microRNA (miRNA) sponging, interacting with RNA‐binding proteins, or even an ability to translate to proteins. A huge challenge in finding diagnostic biomarkers is finding noninvasive biomarkers that can be detected in human fluids, especially blood samples. CircRNAs are becoming candidate biomarkers for diagnosis and prognosis of these diseases through their ability to transverse from the blood‐brain barrier and their broad presence in circulating exosomes. The circRNA for miRNA‐7 (ciRS‐7) is newly recognized, and acknowledged to being related to human pathology and cancer progression. In this review, we first briefly summarize the latest studies about their characteristics, biogenesis, and their mechanisms of action in the regulation and development of human diseases. Finally, we provide a list of diseases that are linked to one member of this novel class of ncRNAs called ciRS‐7.     

The potential of using blood circular RNA as liquid biopsy biomarker for human diseases

Circular RNA (circRNA) is a novel class of single-stranded RNAs with a closed loop structure. The majority of circRNAs are formed by a back-splicing process in pre-mRNA splicing. Their expression is dynamically regulated and shows spatiotemporal patterns among cell types, tissues and developmental stages. CircRNAs have important biological functions in many physiological processes, and their aberrant expression is implicated in many human diseases. Due to their high stability, circRNAs are becoming promising biomarkers in many human diseases, such as cardiovascular diseases, autoimmune diseases and human cancers. In this review, we focus on the translational potential of using human blood circRNAs as liquid biopsy biomarkers for human diseases. We highlight their abundant expression, essential biological functions and significant correlations to human diseases in various components of peripheral blood, including whole blood, blood cells and extracellular vesicles. In addition, we summarize the current knowledge of blood circRNA biomarkers for disease diagnosis or prognosis.     

Characterization of human phosphodiesterase 12 and identification of a novel 2'-5' oligoadenylate nuclease - The ectonucleotide pyrophosphatase/phosphodiesterase 1

The vertebrate 2-5A system is part of the innate immune response and central to cellular antiviral activities. Upon activation by viral double-stranded RNA, 5′-triphosphorylated, 2′-5′-linked oligoadenylate polyribonucleotides (2-5As) are synthesized by one of several 2′-5′ oligoadenylate synthetases. The 2-5As bind and activate RNase L, an unspecific endoribonuclease, resulting in viral and cellular RNA decay. Given that most endogenous RNAs are degraded by RNase L, continued enzyme activity will eventually lead to cell growth arrest and cell death. This is averted, when 2-5As and their 5′-dephosphorylated forms, the so-called 2-5A core molecules, are cleaved and thus inactivated by 2′-5′-specific nuclease(s), e.g. phosphodiesterase 12, thereby turning RNase L into its latent form. In this study, we have characterized the human phosphodiesterase 12 in vitro focusing on its ability to degrade 2-5As and 2-5A core molecules. We have found that the enzyme activity is distributive and is influenced by temperature, pH and divalent cations. This allowed us to determine V_max and K_m kinetic parameters for the enzyme. We have also identified a novel 2′-5′-oligoadenylate nuclease; the human plasma membrane-bound ectonucleotide pyrophosphatase/phosphodiesterase 1, suggesting that 2-5A catabolism may be a multienzyme-regulated process.     

环状RNA及其在生态毒理学研究中的应用进展

环状RNA（circular RNAs,circRNAs）是一类共价闭合环状非编码RNA,具有进化上保守、结构上稳定、组织特异性表达等特点。CircRNAs可作为miRNAs海绵影响其对基因的调控,还可与RNA结合蛋白（RNA binding proteins,RBPs）相互作用,也有研究表明某些circRNAs还具有被翻译成蛋白质的潜能。CircRNAs已被证实对某些疾病具有特异性、稳定性和调节功能,如癌症、糖尿病、心血管疾病、神经退行性疾病等,其可作为潜在的诊断、预后生物标志物和治疗靶点。最近,有研究发现circRNAs参与了环境化学污染物诱导的毒性效应发生及发展的过程。目前,生态毒理学研究中评价环境化学污染物和毒效应之间关系的毒性终点通常会受遗传多态性和表观遗传学影响,考虑到经环境化学污染物暴露后生物体内circRNAs差异性表达的现象,或许在生态毒理学研究中circRNAs也有作为生物标志物的可能性。基于此,对circRNAs的生物合成与降解、生物学功能、分析方法及其目前在生态毒理学研究中的应用展开综述,并对其作为分子生物标志物在环境污染物暴露早期诊断和生态风险评价中的应用进行了展望,以期为生态毒理学研究和环境风险评价提供参考。     

miRNA靶基因的筛选方法及其相关网络资源

微小RNA（microRNA,miRNA）是一类广泛存在于动植物中,大小约22 nt的单链非编码小分子RNA.它通过与靶mRNA 3′末端非翻译区（untranslational region, UTR）结合,使mRNA降解或翻译抑制.大量的研究结果表明,miRNA在动植物的生长发育、细胞分化、细胞增殖与凋亡、肿瘤发生等诸多环节发挥着重要的调节作用.目前,miRNA靶基因的筛选方法主要有生物信息学筛选和实验方法两大类,且在互联网上拥有大量相关的网络共享资源.本文通过对现有miRNA靶基因的筛选方法及其相关网络资源进行整理与比较分析,以有效指导并辅助miRNA领域的研究.