Genotypic Analysis, Construction of the Expression System and Immunological Identification of the Recombinant Proteins of the LipL32 Gene in the Dominant Serogroups of Leptospira interrogans in China

To investigate the existence of the major outer membrane protein (MOMP) gene LipL32 in 15 dominant Chinese strains of 15 serogroups of Leptospira interrogans and 2 international strains of 2 serogroups of Leptospira biflexa, and to clone and construct the expression system as well as to identify the recombinant proteins, genomic DNAs from strains of leptospira were prepared by routine phenol-chloroform method, and the fragments of the LipL32 gene with the whole length from the strains were amplified with high fidelity PCR. The target amplification products were sequenced after T-A cloning, and the expression system for the genes were thereby constructed. Expression of the recombinant proteins was identified by using SDS-PAGE after induction with IPTG at different dosages. Western blot assays with rabbit antiserum against the whole cell of TR/PatocⅠ of Leptospira and immunized serum with rMOMPs were used to determine the immunoreactivity and immunogenicity of the recombinant proteins. Microscopic agglutination test was used to determine the cross- agglutination titres in rabbit sera immunized with rMOMPs, and the cell adherence model of Leptospira was used to examine the blocking effects of rabbit antisera against these rMOMPs. It was found that the LipL32 gene could be found in all the 17 strains of Leptospira mentioned above with two different genotypes, i.e. LipL32/1 and LipL32/2. Amounts of expressions of rMOMP1 and rMOMP2 after IPTG accounted for 40% and 10% of the total bacterial proteins respectively. Both rMOMP1 and rMOMP2 could combine with the rabbit antiserum against leptospiral TR/PatocⅠ, and could induce the production of agglutination antibodies to these 17 strains of Leptospira with 1∶2 to 1∶64 MAT titres. The rabbit anti-rMOMP1 and anti-MOMP2 antibodies at 1∶2 to 1∶16 dilutions could efficiently block adherence of Leptospira. It concludes that all the Leptospira tested in the present study possess LipL32/1 or LipL32/2 genes, and the constructed expression system can express the rMOMP1 and rMOMP2. These recombinant proteins are showed to have good immunogenicity and satisfactory immunoreactivity.

Genome-wide analysis of the barley non-specific lipid transfer protein gene family

Non-specific lipid transfer proteins(nsLTPs) are small, basic proteins that are characterized by an eight-cysteine motif. The biological functions of these proteins have been reported to involve plant reproduction and biotic or abiotic stress response. With the completion of the barley genome sequence, a genome-wide analysis of nsLTPs in barley(Hordeum vulgare L.)(HvLTPs) will be helpful for understanding the function of nsLTPs in plants. We performed a genome-wide analysis of the nsLTP gene family in barley and identified 70 nsLTP genes,which can be divided into five types(1, 2, C, D, and G). Each type of nsLTPs shares similar exon and intron gene structures. Expression analysis showed that barley nsLTPs have diverse expression patterns, revealing their various roles. Our results shed light on the phylogenetic relationships and potential functions of barley nsLTPs and will be useful for future studies of barley development and molecular breeding.

Cloning and Sequence Analysis of the 28.5ku Movement Protein of Frangipani Mosaic Virus (FMV)

Based on conserved regions among genomic RNA of tobamoviruses, a pair of primers spanning the sequence encoding the movement protein were synthesized. A cDNA fragment of 1700bp was thus amplified by RT-PCR(reverse transcription-polymerase chain reaction). The fragment was cloned into pGEM-T easy vector and sequenced. DNA sequence analysis showed that the fragment contained a region of 768 nucleotides encoding protein of 256 amino acid of frangipani mosaic virus (FMV) and also partial sequence corresponding to 180ku and 17. 5ku protein.

Cloning and Sequence Analysis of Carbonic Anhydrase-related Protein 10-like in Apis mellifera

[ Objective ] This study aimed to clone and analyze the gene sequence encoding carbonic anhydrase-related protein lO-like （ CARP X） from Apis mellif era. [Method] The cDNA sequence of CARPX gene was cloned through RT-PCR, and then analyzed with bioinformatic method. [Result] The full-length cDNA sequence of CARPX was 972 bp long and encoded 324 amino acid residues, including a signal peptide and two transmembrane domains. The predicted molecular mass was 37.1 kDa and the predicted isoeleetric point was 7.458. The CARP X from A. mellifera shared close relationship with proteins from Apisflorae, Bombtas impatiens, Bombus terrestris, Nasonia vitripennis and Acyrthosiphon pisum. The insect CARP X family may include two subfamilies. [ Conclusion] The results pro- vide basis for studying CARPs family.

Cloning and Sequence Analysis of IGFBP-7 Gene in Sheep

In this study, full-length CDS sequence of IGFBP-7 gene was cloned from Liangshan semi-fine wool sheep with RT-PCR method and analyzed with bioinformatics methods. The results showed that the full-length CDS sequence of IGFBP-7 gene in Liangshan semi-fine wool sheep was 846 bp in length, encoding 282 amino acids. The CDS sequence shared 99%, 95% and 90% homology with bovine, human and rat, respectively; the amino acid sequence shared 98%, 93% and 89%, respectively. The GenBank accession number was FJ589640.1. The amino acid molecular weight of IGFBP-7 was 29.0 kD, and the theoretical isoelec- tric point （pl） was 8.25. The result of phylogenetic analysis showed that IGFBP-7 gone in Liangshan semi-fine wool sheep exhibited close phylogenetic relationships with bovine, goat and other mammals, and distant phylogenetic relationships with Danio rerio and Haliotis diversicolor. IGFBP-7 gene had uniformly distributed hy- drophobic and hydrophilic regions, harboring one signal peptide, two transmembrane regions, 16 phosphorylation sites, four N-glycosylation sites and one O-glyco- sylation site. The result of secondary structure analysis showed that the random coil, or-helix and β-sheet regions accounted for 64.89%, 19.86% and 15.25%, respectively. The result of tertiary structure analysis showed that IGFBP-7 harbors an IGFBP_N domain and an Ig-like domain. This study provided scientific basis for further investigating the function of IGFBP-7 gene in sheep.

Proteolipid protein 1 gene sequencing of hereditary spastic paraplegia

PCR amplification and sequencing of whole blood DNA from an individual with hereditary spastic paraplegia, as well as family members, revealed a fragment of proteolipid protein 1 （PLP1） gene exon 1, which excluded the possibility of isomer 1 expression for this family. The fragment sequence of exon 3 and exon 5 was consistent with the proteolipid protein 1 sequence at NCBI. In the proband samples, a PLP1 point mutation in exon 4 was detected at the basic group of position 844, T→C, phenylalanine→leucine. In proband samples from a male cousin, the basic group at position 844 was C, but gene sequencing signals revealed mixed signals of T and C, indicating possible mutation at this locus. Results demonstrated that changes in PLP1 exon 4 amino acids were associated with onset of hereditary spastic paraplegia.

Expression of putative zinc-finger protein lcn61 gene in lymphocystis disease virus China (LCDV-cn) genome

An open reading frame (lcn61) of lymphocystis disease virus China (LCDV-cn), probably responsible for encoding putative zinc-finger proteins was amplified and inserted into pET24a (+) vector. Then it expressed in E. coli BL21 (DE3), and His-tag fusion protein of high yield was obtained. It was found that the fusion protein existed in E. coli mainly as inclusion bodies. The bioinformatics analysis indicates that LCN61 is C2H2 type zinc-finger protein containing four C2H2 zinc-finger motifs. This work provides a theory for functional research of lcn61 gene.

Cloning and Sequencing of the Pokeweed Antiviral Protein Gene and Its Expression in E. coli

The total RNA was isolated from pokeweed (Phytolacca americana) leaves using the method of guanidine isothiocyanite and used as a template to amplify the deleted mutant pokeweed antiviral protein (PAP) gene by RT-PCR and then the gene was cloned into the pGEMR-T vector. The sequencing results showed that the PAP gene consisted of 711nt, which was 99.6% identical to the PAP gene reported by Lin et al (1991). The IPTG-inducible expression vector containing the PAP gene was constructed and transferred into the E. coli strain BL21 (DE3)-plysS. A specific protein was produced after induction with 0.4m mol/L IPTG and its molecular weight was 26ku. The results of the double diffusion on the agar plate and the western blotting test showed that the protein produced in E. coli was highly identical with the PAP extracted by a Frenchman from French pokeweed leaves. These revealed that PAP gene was actually achieved and exactly expressed in E. coli.

落叶松-杨栅锈菌MlpMCM4蛋白和MlpHOG1蛋白互作关系初探

由落叶松-杨栅锈菌侵染引起的杨树叶锈病严重威胁杨树的健康生长。通过家族鉴定和系统发育分析确定落叶松-杨栅锈菌标准菌株ID 48743为MCM4直系同源基因,命名为MlpMCM4。以夏孢子cDNA为模板,运用RT-PCR技术,同源克隆获得中国菌株MlpMCM4基因CDS片段,称之为MlpMCM4(wh03),长度为2460 bp,编码819个氨基酸。结果表明,比对分析显示目的蛋白具有保守结构域,包括Walker A、Walker B和R-finger基序,以及MCM4类型锌指结构。亚细胞定位预测显示其定位在细胞核区域。利用基于分离泛素系统的酵母双杂交技术和萤火虫荧光素酶互补试验,没有检测到落叶松-杨栅锈菌中国菌株MlpMCM4蛋白和MlpHOG1蛋白能够相互作用,推断二者相互作用可能需要外源渗透压刺激。

四翅滨藜Osmotin-like Protein基因的克隆、序列分析及其原核表达

在构建四翅滨藜(Atriplex canescens)全长cDNA文库中通过随机克隆测序并进行EST分析基础上,得到四翅滨藜osmotin-like protein的1个cDNA序列,命名为AcOLP。AcOLPcDNA包含一个全长为687 bp完整开放阅读框,编码229个氨基酸,属于GH64-TLP-SF超家族,是一种病程相关5(PR-5)蛋白,其核酸序列与大洋洲滨藜(Atriplex nummularia)的osmotin-likeprotein基因的同源性为94%,对应编码氨基酸序列同源性为87%。将得到的序列提交GenBank,序列号为JN632587.1。与其他植物PR-5蛋白的氨基酸序列比对,AcOLP具有保守的半胱氨酸残基,与二硫键的形成有关。对AcOLP与其他植物的氨基酸序列的进化分析表明,其与大洋洲滨藜的亲缘关系较近。将AcOLP基因与原核表达载体pET-28a连接,进行融合表达,在大肠杆菌BL21(DE3)中诱导表达出分子质量约29 kD的蛋白。

Applying a highly specific and reproducible cDNA RDA method to clone garlic up-regulated genes in human gastric cancer cells

AIM: To develop and optimize cDNA representationaldifference analysis (cDNA RDA) method and to identify andclone garlic up-regulated genes in human gastric cancer(HGC) cells.METHODS: We performed cDNA RDA method by usingabundant double-stranded cDNA messages provided by twoself-constructed cDNA libraries (Allitridi-trested and paternalHGC cell line BGC823 cells cDNA libraries respectively).BamH Ⅰ and Xho I restriction sites harbored in the libraryvector were used to select representations. Northern andSlot blots analyses were employed to identify the obtaineddifference products.RESJLTS: Fragments released from the cDNA library vectorafter restriction endonuclease digestion acted as goodmarker indicating the appropriate digestion degree for libraryDNA. Two novel expressed sequence tags (ESTs) and arecombinant gene were obtained. Slot blots result showed a8-fold increase of gila-derived nexin/protease nexin 1 (GDN/PN1 ) gene expression level and 4-fold increase of hepatitis Bvirus x-interacting protein (XIP) mRNA level in BGC823 cellsafter Allitridi treatment for 72 h.CONCLUSION: Elevated levels of GDN/PN1 and XIP mRNAsinduced by Allitridi provide valuable molecular evidence forelucidating the garlic' s efficacies against neurodegenerativeand inflammatory diseases. Isolation of a recombinant geneand two novel ESTs further show cDNA RDA based on cDNAlibraries to be a powerful method with high specificity andreproducibility in cloning differentially expressed genes.

Fine-mapping and characterisation of genes on barley(Hordeum vulgare)chromosome 2H for salinity stress tolerance during germination

Salinity causes a detrimental impact on plant growth,particularly when the stress occurs during germination and early development stages.Barley is one of the most salt-tolerant crops;previously we mapped two quantitative trait loci(QTL)for salinity tolerance during germination on the short arm of chromosome 2 H using a CM72/Gairdner doubled haploid(DH)population.Here,we narrowed down the major QTL to a region of 0.341 or 0.439 Mb containing 9 or 24 candidate genes belonging to 6 or 20 functional gene families according to barley reference genomes v1 and v3 respectively,using two DH populations of CM72/Gairdner and Skiff/CM72,F_(2)and F;generations of CM72/Gairdner/;Spartacus CL,Two Receptorlike kinase 4(RLPK4)v1 or Receptor-like kinase(RLK)v3 could be the candidates for enhanced germination under salinity stress because of their upregulated expression in salt-tolerant variety CM72.Besides,several insertion/deletion polymorphisms were identified within the 3 rd exon of the genes between CM72 and Gairdner.The sequence variations resulted in shifted functional protein domains,which may be associated with differences in salinity tolerance.Two molecular markers were designed for selecting the locus with receptor-like protein kinase 4,and one was inside HORVU2 Hr1 G111760.1 or HORVU.MOREX.r3.2 HG0202810.1.The diagnostic markers will allow for pyramiding of 2 H locus in barley varieties and facilitate genetic improvement for saline soils.Further,validation of the genes to elucidate the mechanisms involved in enhancing salinity tolerance at germination and designing RLPK4 specific markers is proposed.For this publication,all the analysis was based on barley reference genome of2017(v1),and it was used throughout for consistence.However,the positions of the markers and genes identified were updated according to new genome(v3)for reference.

Overexpression of a novel gene , Cms1, can rescue the growth arrest of a Saccharomyces cerevisiae mcm10 suppressor

MCM10 protein is an essential replication factor involved in the initiation of DNA replication. A mcm10 mutan (mcm10-1) of budding yeast shows a growth arrest at 37 C. In the present work, we have isolated a mcm10-1 suppressor strain, which grows at 37 C. Interestingly, this mcm10-1 suppressor undergoes cell Cycle arrest at 14 C. A novel gene, YLR003c, is identified by high-copy complementation of this suppressor. We called it as Cms1 (Complementation of Mcm 10 Suppressor). Furthermore, the experiments of trans- formation show that cells of mcm10-1 suppressor with high-copy plasmid but not low-copy plasmid grow at 14 C, indicating that overexpression of Cms1 can rescue the growth arrest of this mcm10 suppressor at non-permissive temperature. These results suggest that CMS1 protein may functionally interact with MCM10 protein and play a role in the regulation of DNA replication and cell cycle control.

Screening and Primary Characterization of NewAntigen Genes of Schistosoma Japonicum

To find Schistosoma japonicum(S.j)new antigen gene thus provide more useful vaccine candidates, the cDNA library of S.j adult worm was screened with sera of rabbits immunized with the membrane antigens of Schistosoma japonicum hepato-portal schistosomula (SjHmAg). The positive clones were amplified by PCR and sequenced, then the sequences of clones were compared with all sequences in GenBank database using Blast process. The new clones were submitted to GenBank for accession numbers. Fifteen positive clones were obtained after three rounds of immunoscreening. The size of S.j cDNA fragments in positive clones ranged from 0.7?kb-3.0?kb after automatically excised with the helper phage. Sequence analysis revealed that partial sequence of clone M5 had significant homology with S.j mitochondria mRNA, the other positive clones were new S.j genes. M2 clone sequence (GenBank accession number AF502579) was 730?bp long it had a 117?bp open reading frame (ORF). The sequence of M15 (GenBank accession number AF502582) has no transmembrane region and encodes 92 amino acids, and its protein contains a ferredoxins iron-sulfur binding region signature and two VWFC signal regions. The size of M1、M8、M9、M12(GenBank accession numbers: AF502578, AF502580, AF500622, AF502581) ranges from 402?bp to 766?bp. It concluded that the sera from rabbit immunized with SjHmAg could recognize S.j specific antigens molecules, and these antigens may induce the protective immunity against S.j infection.

1株牛病毒性腹泻病毒的分离鉴定及其结构蛋白E2序列分析

为了解河北省唐山市规模化奶牛场中牛病毒性腹泻病毒(BVDV)流行毒株的基因特征,本试验于唐山市2个规模化奶牛场采集了49份临床样品进行逆转录聚合酶链式反应(RT-PCR)检测,并对阳性样品进行病毒的分离,最终成功分离到1株非致细胞病变的BVDV毒株,命名为HB-1株。电镜观察结果显示,HB-1株具有典型的BVDV病毒粒子形态。对HB-1株全基因组序列进行扩增和测序,基因遗传进化分析结果显示,HB-1株属于BVDV-1m亚型。HB-1株结构蛋白E2全长序列糖基化位点和抗原表位预测结果显示,HB-1株E2蛋白含有4个保守的糖基化位点,其中抗原表位1高度保守。本试验为河北省进一步开展牛病毒性腹泻(BVD)流行病学调查、疫苗株筛选以及检测方法建立提供数据支撑。

绿豆象热激蛋白超家族基因的鉴定及表达分析

【目的】鉴定绿豆象(Callosobruchus chinensis)热激蛋白(heat shock protein,HSP)超家族基因成员,明确高、低温胁迫后HSP基因在绿豆象中的表达变化,为深入挖掘HSP基因功能提供理论依据。【方法】从Insect Base 2.0下载不同昆虫HSP基因的CDS和蛋白序列,并以此为参考在绿豆象全长转录组测序数据库中进行本地BLASTp和tBLASTn比对搜索,同时结合HMMER和关键词两种方法再次筛选目标序列,最终完成搜索结果的汇总。利用CDD、MEGA、ProtParam等在线分析工具对绿豆象HSP超家族基因进行生物信息学分析。根据绿豆象成虫高、低温转录组测序数据筛选出7个候选CcHsp,采用实时荧光定量PCR(qRT-PCR)技术比较分析其在绿豆象不同虫态(幼虫、蛹、成虫)及不同温度胁迫下的表达特性。【结果】共鉴定出31个HSP基因,其中包括3个HSP90、8个HSP70、8个HSP60和12个sHSP(small HSP)。理化性质分析显示CcHsp编码的蛋白质包含159—776个氨基酸残基(aa),分子量介于18.4—88.9 kDa,理论等电点为4.95—9.17。亚细胞定位结果显示多数CcHsp定位于细胞质中,少数基因定位于线粒体基质、内质网和细胞核。系统发育分析表明绿豆象热激蛋白不同家族成员与其他昆虫的热激蛋白进化关系较近,显示了其在进化上的保守性。qRT-PCR分析发现,不同虫态在不同温度胁迫后7个候选CcHsp差异表达。CcHsp20.102经高温胁迫后在雌、雄成虫体内的表达量分别上调1000和500倍;CcHsp70-5经高温胁迫后在雌、雄成虫体内的表达量分别上调500和450倍;幼虫经高、低温胁迫后,CcHsp19.855和CcHsp70-5表达差异显著。【结论】通过绿豆象全长转录组测序数据共鉴定出31个完整的热激蛋白超家族基因成员,分为4个亚家族,家族间蛋白结构、保守结构域和基因表达特征存在差异。CcHsp20.102和CcHsp70-5可能在成虫抵御高温胁迫中行使重要功能,而幼虫的高温耐受性可能与CcHsp19.855和CcHsp70-5的表达差异有关。

中国沙棘HrNHX6基因克隆及其在干旱胁迫下的表达分析

【目的】克隆中国沙棘HrNHX6基因,分析其在干旱胁迫下的表达,以期为HrNHX6基因的抗旱功能研究提供参考依据。【方法】对中国沙棘HrNHX6基因进行扩增,并利用生物软件分析HrNHX6基因序列,预测其蛋白结构,在此基础上对干旱胁迫下HrNHX6基因的表达进行分析。【结果】获得的HrNHX6基因属于NHX家族NHX6基因,其编码蛋白质定位于液泡膜,无信号肽,含有13个跨膜螺旋区,具有N-糖基化位点、蛋白激酶磷酸化位点、豆蔻酰化位点、酰胺化位点、糖转运蛋白signature位点等多种类型的修饰位点。qRT-PCR分析结果表明,干旱胁迫下不同组织之间HrNHX6基因的表达水平具显著差异,而不同干旱程度胁迫处理之间HrNHX6基因的表达水平呈极显著差异。【结论】HrNHX6蛋白的结构特性及HrNHX6基因在干旱胁迫下的表达模式表明其与中国沙棘抗旱关系密切且受干旱胁迫诱导。

肾小管间质性肾病基因-表型关联性分析

目的:筛选肾小管间质性肾病遗传变异枢纽基因。方法:对经肾活检证实且无明确病因的24例肾小管间质性肾病患者进行全外显子组测序,应用Phenolyzer数据库进行基因-表型关联评分,筛选其共有的罕见遗传变异,利用DAVID 6.8数据库进行基因功能通路富集分析。应用String数据库构建PPI网络图,并使用Cytoscape中的插件cytoHubba进行可视化分析,寻找枢纽基因。应用SWISS-Pdb Viewer软件分析枢纽基因突变前后表达蛋白三级结构的变化。结果:24例中女9例,男15例,年龄18~40(26.17±8.82)岁。全外显子组测序检测出19例患者携带致病或可能致病的基因突变位点,共发现35个肾小管间质性肾病易感基因,其在TGF-β信号通路、细胞因子-细胞因子受体相互作用信号通路中富集。PPI网络和Cytoscape分析筛选出4个枢纽基因,即VCP、PRKDC、RBPJ、MYH11,且VCP基因突变造成蛋白质空间结构和功能的改变。结论:肾小管间质性肾病易感基因主要富集在离子跨膜转运的调节、蛋白质转运的调控、蛋白质磷酸化等生物过程,TGF-β信号通路、细胞因子-细胞因子受体相互作用信号通路中。VCP基因可能与肾小管间质性肾病有关。

基于WES识别中国人群甲状腺乳头状癌新易感基因变异EPB41L4A rs1455421289

目的采用全外显子组测序(WES)结合靶向分析识别中国人群甲状腺乳头状癌(PTC)新的易感基因变异。方法选取2018—2020年北京医院行手术治疗的PTC患者286例,用于识别PTC候选基因的变异位点。选取2021—2022年北京医院行手术治疗的PTC患者214例,用于验证变异位点的突变频率。采用WES检测所有研究对象外周血白细胞基因组DNA,并采用靶向分析识别全基因组关联研究(GWAS)定位的28个PTC候选基因的蛋白编码区,及其侧翼选择性剪接序列的罕见变异。检测变异携带者癌组织和癌旁组织中变异位点等位基因的表达情况。通过病例-对照关联分析评估变异位点对PTC发生风险的影响。对照人群的基因分型数据分别来自gnomAD数据库、TOPMed数据库、ChinaMAP数据库和HUABIAO数据库。结果WES结合靶向分析识别出红细胞膜蛋白4.1样4A(EPB41L4A)基因上的2个极罕见错义突变(rs1455421289位点c.163G>C:p.D55H和rs761977647位点c.855G>C:p.W285C),可能潜在影响编码蛋白的功能。在用于识别PTC候选基因变异位点的286例PTC患者中,有3例携带rs1455421289位点c.163G>C:p.D55H变异,1例携带rs761977647位点c.855G>C:p.W285C变异。这2个位点在4个对照人群中的携带频率均<0.05%。在用于计算变异位点突变频率的214例PTC患者中,有1例携带rs1455421289位点c.163G>C:p.D55H变异,未发现rs761977647位点c.855G>C:p.W285C变异。EPB41L4A rs1455421289的突变频率为0.8%(4/500),rs761977647的突变频率为0.2%(1/500)。EPB41L4A rs1455421289变异导致突变型mRNA的表达丰度显著高于野生型mRNA(P<0.01)。与4个对照人群比较,携带rs1455421289位点c.163G>C:p.D55H变异者PTC发生风险显著升高[比值比(OR)]值分别为40.3、85.4、213.5、541.1,95%可信区间(CI)分别为4.5~361.5、9.5~765.4、57.2~797.2、98.9~2960.8。结论基于WES识别出1个新的PTC易感基因变异EPB41L4A rs1455421289,该变异位点携带者PTC的发生风险显著增高。

鸡MDA5的序列分析与结构域预测

为了解鸡黑色素瘤分化相关基因-5(Melanoma differentiation-associated protein 5,MDA5)的序列和结构域,试验使用PCR方法扩增了鸡MDA5基因并构建真核表达质粒,实现了鸡MDA5蛋白的真核表达,同时利用MegAlign等软件对鸡MDA5氨基酸序列进行分析。结果显示:鸡MDA5全长3 006 bp,编码1 001个氨基酸;鸡MDA5与人、猕猴、野猪、小鼠、绿头鸭、灰雁、鸿雁、鲫鱼、草鱼的氨基酸相似性分别为62.4%、62.9%、62.7%、64.1%、86.8%、87.3%、87.4%、48.1%、46.3%;鸡MDA5与鸟类进化关系较近,与哺乳动物次之,与鱼类进化关系较远;鸡MDA5由N端两个半胱天冬酶激活招募结构域、DExD/H box RNA解旋酶结构域和C端结构域组成;鸡MDA5二级结构包含α螺旋(50.95%)、延伸链(11.19%)、β转角(3.9%)和无规则卷曲(33.97%),三级结构与人MDA5类似,在空间上呈现半闭合环状结构。研究成功鉴定了鸡MDA5基因,分析了其基因序列并预测其结构域,为深入研究鸡MDA5结构与功能及其在鸡抗病毒天然免疫应答中的作用奠定基础。