Identification of the DEAD-box RNA helicase family members in grapevine reveals that VviDEADRH25a confers tolerance to drought stress

Grapevine growing areas are increasingly affected by drought,which has greatly limited global wine production and quality.DEAD-box is one of the largest subfamilies of the RNA helicase family,and its members play key roles in the growth and development of plants and their stress responses.Previous studies have shown the potential of DEAD-box genes in the drought stress responses of Arabidopsis and tomato,rice,and other crop species.However,information about DEAD-box genes in grapevine remains limited.In this report,a total of 40 DEAD-box genes were identified in grapevine and their protein sequence characteristics and gene structures were analyzed.By comparing the expression profiles of VviDEADRHs in response to drought stress in different grapevine varieties,nine candidate genes(VviDEADRH10c,-13,-22,-25a,-25b,-33,-34,-36,and-39)were screened based on expression profiling data.Combined with qRTPCR results,Vvi DEADRH25a was selected for functional verification.Heterologous overexpression of Vvi DEADRH25a in Arabidopsis showed the transgenic plants were more sensitive to drought stress than the control.Both electrolyte permeability and malondialdehyde content were significantly increased in transgenic plants,whereas the chlorophyll content and superoxide dismutase(SOD),peroxidase(POD),catalase(CAT),and ascorbate peroxidase(APX)enzyme activities were significantly decreased.Furthermore,VviDEADRH25a-overexpressing plants showed down-regulated expression levels of several drought stress-related marker genes,namely At COR15a,At RD29A,At ERD15,and At P5CS1,which indicated that they participated in the drought stress response.In summary,this study provides new insights into the structure,evolution,and participation of DEAD-box RNA helicase genes in the response to drought stress in grapevines.

Heat shock protein 90 promotes RNA helicase DDX5 accumulation and exacerbates hepatocellular carcinoma by inhibiting autophagy

Objective:Hepatocellular carcinoma(HCC),the main type of liver cancer,has a high morbidity and mortality,and a poor prognosis.RNA helicase DDX5,which acts as a transcriptional co-regulator,is overexpressed in most malignant tumors and promotes cancer cell growth.Heat shock protein 90(HSP90)is an important molecular chaperone in the conformational maturation and stabilization of numerous proteins involved in cell growth or survival.Methods:DDX5 m RNA and protein expression in surgically resected HCC tissues from 24 Asian patients were detected by quantitative real-time PCR and Western blot,respectively.The interaction of DDX5-HSP90 was determined by molecular docking,immunoprecipitation,and laser scanning confocal microscopy.The autophagy signal was detected by Western blot.The cell functions and signaling pathways of DDX5 were determined in 2 HCC cell lines.Two different murine HCC xenograft models were used to determine the function of DDX5 and the therapeutic effect of an HSP90 inhibitor.Results:HSP90 interacted directly with DDX5 and inhibited DDX5 protein degradation in the AMPK/ULK1-regulated autophagy pathway.The subsequent accumulation of DDX5 protein induced the malignant phenotype of HCC by activating theβ-catenin signaling pathway.The silencing of DDX5 or treatment with HSP90 inhibitor both blocked in vivo tumor growth in a murine HCC xenograft model.High levels of HSP90 and DDX5 protein were associated with poor prognoses.Conclusions:HSP90 interacted with DDX5 protein and subsequently protected DDX5 protein from AMPK/ULK1-regulated autophagic degradation.DDX5 and HSP90 are therefore potential therapeutic targets for HCC.

RNA解旋酶DDX5在病理生理作用中的研究进展

RNA解旋酶DDX5(DEAD-box helicase 5)是具有多种生物学功能的核蛋白,对多种转录因子有激活作用,且在mRNA、rRNA、miRNA加工,核糖体合成,细胞增殖及分化,细胞骨架重塑,细胞凋亡中发挥十分重要的作用。在血管疾病中,DDX5可以引起动脉粥样硬化的加剧及抑制血管重构。研究表明DDX5与多种肿瘤的发生、调控的解除及关键致癌因子基因的表达有关。此外DDX5还参与神经系统疾病、肾病及肥胖症等疾病的发生与发展。深入探讨DDX5的结构特点,生物学功能与病理生理作用能够为众多临床相关疾病提供治疗参考。

小鼠CHD5基因siRNA重组腺病毒载体的构建及鉴定

目的:构建小鼠染色质区解旋酶DNA结合蛋白5(CHD5)基因干扰RNA(small interfering RNA,siRNA)重组腺病毒载体并在NIH3T3细胞中验证其干扰作用.方法:人工合成靶向CHD5的siRNA干扰序列,用分子克隆的方法插入到穿梭载体pSES-HUS上,并与腺病毒骨架质粒pAdeasy-1在BJ5183细菌中进行同源重组,得到pAdeasy-SES-HUS-CHD5siRNA重组质粒,在HEK293细胞中包装成重组腺病毒Adr-simCHD5,然后感染NIH3T3细胞,用RT-PCR和Western Blot方法检测其对CHD5mRNA和蛋白表达的干扰效果.结果:得到高滴度Adr-CHD5siRNA重组腺病毒,RT-PCR和Western Blot结果表明该重组腺病毒能有效地降低CHD5基因的表达.结论:成功构建Adr-CHD5siRNA重组腺病毒载体,并在NIH3T3细胞上实现CHD5基因表达抑制,为进一步研究CHD5基因功能奠定了基础.

Post-transcriptional regulation of DEAD-box RNA helicases in hematopoietic malignancies

Hematopoiesis represents a meticulously regulated and dynamic biological process.Genetic aberrations affecting blood cells,induced by various factors,frequently give rise to hematological tumors.These instances are often accompanied by a multitude of abnormal post-transcriptional regulatory events,including RNA alternative splicing,RNA localization,RNA degradation,and storage.Notably,post-transcriptional regulation plays a pivotal role in preserving hematopoietic homeostasis.The DEAD-Box RNA helicase genes emerge as crucial post-transcriptional regulatory factors,intricately involved in sustaining normal hematopoiesis through diverse mechanisms such as RNA alternative splicing,RNA modification,and ribosome assembly.This review consolidates the existing knowledge on the role of DEAD-box RNA helicases in regulating normal hematopoiesis and underscores the pathogenicity of mutant DEADBox RNA helicases in malignant hematopoiesis.Emphasis is placed on elucidating both the positive and negative contributions of DEAD-box RNA helicases within the hematopoietic system.

乌头碱调控miR-181d-5p/DDX3轴对宫颈癌HeLa细胞增殖、凋亡的影响

目的探讨乌头碱通过调控微小RNA-181d-5p(miR-181d-5p)/DEAD-box RNA解旋酶3(DDX3)轴对宫颈癌HeLa细胞增殖、凋亡的影响。方法使用不同剂量乌头碱处理宫颈癌HeLa细胞,四甲基偶氮唑盐法检测细胞增殖确定给药剂量。将HeLa细胞分为对照组(正常培养,不进行处理),乌头碱低剂量组(4 mg/L)、中剂量组(8 mg/L)、高剂量组(16 mg/L),顺铂组(5 mg/L),乌头碱高剂量+miR-NC组[16 mg/L乌头碱+转染miR-181d-5p siRNA阴性对照(miR-NC)质粒]及乌头碱高剂量+miR-181d-5p低表达组[16 mg/L乌头碱+转染miR-181d-5p小干扰RNA(siRNA)质粒]。平板克隆形成实验及流式细胞仪分别检测各组HeLa细胞克隆形成数与凋亡情况;实时荧光定量PCR检测HeLa细胞中miR-181d-5p和DDX3 mRNA表达水平;蛋白免疫印迹法检测HeLa细胞中DDX3、细胞周期蛋白D1(Cyclin D1)、增殖细胞核抗原(PCNA)、B淋巴细胞瘤-2(Bcl-2)、Bcl-2相关X蛋白(Bax)、胱天蛋白酶-3(Caspase-3)蛋白表达水平;双萤光素酶报告基因实验验证miR-181d-5p与DDX3的靶向关系。结果以0.5~64 mg/L的乌头碱分别处理HeLa细胞24 h、48 h、72 h后,对HeLa细胞均有不同程度的抑制作用,选择剂量为4 mg/L、8 mg/L、16 mg/L的乌头碱用于后续实验。与对照组比较,乌头碱低、中、高剂量组及顺铂组HeLa细胞克隆形成数、DDX3 mRNA和蛋白、Cyclin D1、PCNA、Bcl-2蛋白表达水平依次降低(P<0.05),凋亡率、miR-181d-5p、Bax、Caspase-3蛋白表达水平依次升高(P<0.05);与乌头碱高剂量组和乌头碱高剂量+miR-NC组比较,乌头碱高剂量+miR-181d-5p低表达组HeLa细胞克隆形成数、DDX3 mRNA和蛋白、Cyclin D1、PCNA、Bcl-2蛋白表达水平升高(P<0.05),凋亡率、miR-181d-5p、Bax、Caspase-3蛋白表达水平降低(P<0.05);双萤光素酶报告基因检测证实miR-181d-5p与DDX3存在靶向关系。结论乌头碱可调控miR-181d-5p/DDX3轴,促进miR-181d-5p表达,抑制DDX3表达,进而抑制宫颈癌HeLa细胞增殖,促进细胞凋亡。

The DEAD-Box RNA Helicase DDX1 Interacts with the Viral Protein 3D and Inhibits Foot-and-Mouth Disease Virus Replication

Foot-and-mouth disease virus(FMDV)can infect domestic and wild cloven-hoofed animals.The non-structural protein 3D plays an important role in FMDV replication and pathogenesis.However,the interaction partners of 3D,and the effects of those interactions on FMDV replication,remain incompletely elucidated.In the present study,using the yeast two-hybrid system,we identified a porcine cell protein,DEAD-box RNA helicase 1(DDX1),which interacted with FMDV 3D.The DDX1-3D interaction was further confirmed by co-immunoprecipitation experiments and an indirect immunofluorescence assay(IFA)in porcine kidney 15(PK-15)cells.DDX1 was reported to either inhibit or facilitate viral replication and regulate host innate immune responses.However,the roles of DDX1 during FMDV infection remain unclear.Our results revealed that DDX1 inhibited FMDV replication in an ATPase/helicase activity-dependent manner.In addition,DDX1 stimulated IFN-p activation in FMDV-infected cells.Together,our results expand the body of knowledge regarding the role of DDX1 in FMDV infection.

DEAD-box RNA helicases with special reference to p68:Unwinding their biology,versatility,and therapeutic opportunity in cancer

In the era of advancement,the entire world continues to remain baffled by the increased rate of progression of cancer.There has been an unending search for novel thera-peutic targets and prognostic markers to curb the oncogenic scenario.The DEAD-box RNA he-licases are a large family of proteins characterized by their evolutionary conserved D-E-A-D(Asp-Glu-Ala-Asp)domain and merit consideration in the oncogenic platform.They perform multidimensional functions in RNA metabolism and also in the pathology of cancers.Their bio-logical role ranges from ribosome biogenesis,RNA unwinding,splicing,modification of second-ary and tertiary RNA structures to acting as transcriptional coactivators/repressors of various important oncogenic genes.They also play a crucial role in accelerating oncogenesis by pro-moting cell proliferation and metastasis.DDX5(p68)is one of the archetypal members of this family of proteins and has gained a lot of attention due to its oncogenic attribute.It is found to be overexpressed in major cancer types such as colon,brain,breast,and prostate cancer.It exhibits its multifaceted nature by not only coactivating genes implicated in cancers but also mediating crosstalk across major signaling pathways in cancer.Therefore,in this review,we aim to illustrate a comprehensive overview of DEAD-box RNA helicases especially p68 by focusing on their multifaceted roles in different cancers and the various signaling pathways affected by them.Further,we have also briefly discoursed the therapeutic interventional approaches with the DEAD-box RNA helicases as the pharmacological targets for designing in-hibitors to pave way for cancer therapy.

The nonstructural protein 2C of Coxsackie B virus has RNA helicase and chaperoning activities

RNA-remodeling proteins,including RNA helicases and chaperones,play vital roles in the remodeling of structured RNAs.During viral replication,viruses require RNA-remodeling proteins to facilitate proper folding and/or re-folding the viral RNA elements.Coxsackieviruses B3(CVB3)and Coxsackieviruses B5(CVB5),belonging to the genus Enterovirus in the family Picornaviridae,have been reported to cause various infectious diseases such as hand-foot-and-mouth disease,aseptic meningitis,and viral myocarditis.However,little is known about whether CVB3 and CVB5 encode any RNA remodeling proteins.In this study,we showed that 2C proteins of CVB3 and CVB5 contained the conserved SF3 helicase A,B,and C motifs,and functioned not only as RNA helicase that unwound RNA helix bidirectionally in an NTP-dependent manner,but also as RNA chaperone that remodeled structured RNAs and facilitated RNA strand annealing independently of NTP.In addition,we determined that the NTPase activity and RNA helicase activity of 2C proteins of CVB3 and CVB5 were dependent on the presence of divalent metallic ions.Our findings demonstrate that 2C proteins of CVBs possess RNA-remodeling activity and underline the functional importance of 2C protein in the life cycle of CVBs.

DDX10对肿瘤增殖凋亡影响的研究进展

DDX10(DEAD-box helicase10)是编码RNA解旋酶的DDX蛋白家族成员之一。该家族成员最早被发现能够参与胚胎形成、精子发生以及细胞分裂和生长,且其家族许多成员与肿瘤发生发展密切相关。DDX10能够通过激活多种转录因子的产生,在核糖体合成、细胞增殖和凋亡等多种生物学过程中发挥着重要作用。多项研究发现,DDX10在卵巢细胞癌、肝细胞癌、急性髓系白血病、骨肉瘤等多种肿瘤组织中表达异常。

DEAD盒RNA解螺旋酶5和微小RNA-205在前列腺癌中的表达及临床意义

目的检测DEAD盒RNA解螺旋酶5(DDX5)和微小RNA-205(miR-205)在前列腺癌(PCa)中的表达情况,并分析二者与PCa预后的关系.方法选取2015年4月至2017年4月于北京市朝阳区双桥医院行前列腺癌根治术或穿刺活检术的86例PCa患者为研究对象,取患者术中切除的癌组织及癌旁组织分别作为PCa组和对照组.采用实时荧光定量PCR(qRT-PCR)法检测组织中DDX5 mRNA、miR-205的水平.采用免疫组化法检测组织中DDX5的表达情况.分析DDX5、miR-205表达水平与临床病理特征的关系.采用Kaplan-Meier生存分析DDX5、miR-205表达水平与PCa患者的预后关系.采用Cox回归分析PCa预后不良的影响因素.结果PCa组的DDX5 mRNA及蛋白表达水平均高于对照组(均P<0.05),miR-205表达水平低于对照组(P<0.05).PCa患者中DDX5、miR-205表达与肿瘤分期、血清PSA、Gleason评分、肿瘤转移均有相关性(均P<0.05),而与患者年龄、切缘性质均无相关性(均P>0.05).经Kaplan-Meier生存分析,DDX5阳性表达患者的3年累积生存率低于DDX5阴性表达患者(P<0.05);miR-205高表达患者的3年累积生存率高于miR-205低表达患者(P<0.05).多因素Cox分析结果显示,DDX5水平偏高、miR-205水平偏低是PCa不良预后的危险因素(HR=2.598、3.342,均P<0.01).结论在PCa患者癌组织中DDX5高表达,miR-205低表达,二者与PCa的多种临床病理及预后有关,是PCa患者预后不良的危险因素.

登革病毒非结构蛋白NS3研究进展

登革病毒非结构蛋白NS3是一种多功能蛋白,N端具有Ser蛋白酶活性,C端具有RNA解旋酶及NTP磷酸酶、5'RNA三磷酸酶等活性,参与病毒前体的加工和病毒RNA的复制及基因组RNA的5'端加帽。NS3具有良好的免疫原性,存在多个登革病毒特异性CD4+、CD8+T细胞表位,且多具有型间交叉免疫特性。登革病毒非结构蛋白NS3已成为有吸引力的抗病毒靶标。

DDX5在恶性肿瘤中作用机制的研究进展

DDX5解螺旋酶(DEAD box helicases 5)又名P68,是一类依赖ATP的RNA解螺旋酶中重要成员之一。研究表明,DDX5在多种癌症中异常表达,靶向多种肿瘤相关的信号通路,调控上下游的因子从而影响肿瘤细胞的发生、侵袭及迁移。本文阐述DDX5在恶性肿瘤的生物学作用,为肿瘤的靶向治疗提供可能方向。