DEAD-box解旋酶21对猪传染性胃肠炎病毒复制的调控作用

旨在探究DEAD-box解旋酶21(DDX21)对猪传染性胃肠炎病毒(TGEV)复制的调控作用。首先通过蛋白免疫印迹(Western Blot)分析了TGEV感染对DDX21表达的影响;进一步构建了猪DDX21真核表达质粒以及建立稳定敲低DDX21的PK-15细胞系,运用荧光定量PCR(RT-qPCR)、蛋白免疫印迹、间接免疫荧光(IFA)和半数细胞培养物感染量(TCID 50)探究外源过表达DDX21及敲低DDX21对TGEV体外复制的调控作用;构建一系列DDX21截短突变体真核表达质粒,鉴定了DDX21调控TGEV增殖的关键功能域。Western Blot分析显示,在TGEV WH-1株感染早期,PK-15细胞内源性DDX21蛋白的表达水平显著上调;RT-qPCR、Western Blot、IFA和TCID 50试验显示,超表达DDX21可以显著提高TGEV N基因的mRNA水平、N蛋白的表达及病毒滴度,且呈剂量依赖性,其601-784 aa区域是其影响TGEV复制的关键;与阴性对照相比,在相应DDX21敲低细胞系中TGEV的增殖显著被抑制,而回补试验逆转了DDX21敲低细胞系中TGEV的滴度。该研究首次揭示了猪DDX21对TGEV增殖的促进作用并鉴定了其调控TGEV复制的关键结构域,为今后研究DDX21蛋白的功能及TGEV的致病机理提供了理论依据。

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.

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 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.

Systematic Genome-Wide Profiles Reveal Alternative Splicing Landscape and Implications of Splicing Regulator DExD-Box Helicase 21 in Aggressive Progression of Adrenocortical Carcinoma

Alternative splicing(AS)in the tumor biological process has provided a novel perspective on carcinogenesis.However,the clinical significance of individual AS patterns of adrenocortical carcinoma(ACC)has been underestimated,and in-depth investigations are lacking.We selected 76 ACC samples from the Cancer Genome Atlas(TCGA)SpliceSeq and SpliceAid2 databases,and 39 ACC samples from Fudan University Shanghai Cancer Center(FUSCC).Prognosis-related AS events(PASEs)and survival analysis were evaluated based on prediction models constructed by machine-learning algorithm.In total,23,984 AS events and 3,614 PASEs were detected in the patients with ACC.The predicted risk score of each patient suggested that eight PASEs groups were significantly correlated with the clinical outcomes of these patients(p<0.001).Prognostic models produced AUC values of 0.907 in all PASEs’groups.Eight splicing factors(SFs),including BAG2,CXorf56,DExD-Box Helicase 21(DDX21),HSPB1,MBNL3,MSI1,RBMXL2,and SEC31B,were identified in regulatory networks of ACC.DDX21 was identified and validated as a novel clinical promoter and therapeutic target in 115 patients with ACC from TCGA and FUSCC cohorts.In conclusion,the strict standards used in this study ensured the systematic discovery of profiles of AS events using genome-wide cohorts.Our findings contribute to a comprehensive understanding of the landscape and underlying mechanism of AS,providing valuable insights into the potential usages of DDX21 for predict-ing prognosis for patients with ACC.

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。

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.