African Swine Fever Virus MGF-110-9L-deficient Mutant Has Attenuated Virulence in Pigs

African swine fever virus(ASFV) is the etiological agent of African swine fever(ASF), an often lethal disease in domestic and wild pigs. ASF represents a major threat to the swine industry worldwide. Currently, no commercial vaccine is available because of the complexity of ASFV or biosecurity concerns. Live attenuated viruses that are naturally isolated or genetically manipulated have demonstrated reliable protection against homologous ASFV strain challenge. In the present study, a mutant ASFV strain with the deletion of ASFV MGF-110-9 L(ASFV-D9 L) was generated from a highly virulent ASFV CN/GS/2018 parental strain, a genotype II ASFV. Relative to the parental ASFV isolate, deletion of the MGF-110-9 L gene significantly decreased the ability of ASFV-D9 L to replicate in vitro in primary swine macrophage cell cultures. The majority of animals inoculated intramuscularly with a low dose of ASFV-D9 L(10 HAD50) remained clinically normal during the 21-day observational period. Three of five ASFV-D9 L-infected animals displayed low viremia titers and low virus shedding and developed a strong virus-specific antibody response, indicating partial attenuation of the ASFV-D9 L strain in pigs. The findings imply the potential usefulness of the ASFV-D9 L strain for further development of ASF control measures.     

Genetic Analysis of Human Adenovirus Type 7 Strains Circulating in Different Parts of China

To investigate the molecular epidemiology and genetic variation of human adenovirus type 7(HAdV-7) in children with acute respiratory infections(ARI) in China. HAdV-7-positive respiratory samples collected from children with ARI in Beijing, Shijiazhuang, Wenzhou and Guangzhou from 2014–2018 were selected for gene amplification and sequence analysis. Fifty-seven HAdV-7 clinical strains with hexon, penton base and fiber gene sequences were obtained. Meanwhile17 strains were selected randomly from different cities for whole genome sequencing. Phylogenetic and variation analyses were performed based on the obtained sequences, HAdV-7 prototype strain Gomen(AY594255), vaccine strains(AY495969 and AY594256) and representative sequences of strains. The phylogenetic trees constructed based on whole genome sequences, major capsid protein genes(hexon, penton base and fiber) and the early genes(E1, E2, E3 and E4) were not completely consistent. The HAdV-7 strains obtained in this study always clustered with most of the circulating strains worldwide from the 1980 s to the present. Compared with the HAdV-7 prototype strain Gomen(AY594255), some amino acid mutations in loop1 and loop2 of hexon and the RGD loop region of the penton base gene were observed. Recombination analysis showed that partial regions of 55 k Da protein and 100 kDa hexon-assembly associated protein genes among all HAdV-7 strains in this study were from HAdV-16 and HAdV-3, respectively. Our study demonstrated the molecular evolution characteristics of HAdV-7 strains circulating in China and provided basic reference data for the prevention, control and vaccine development of HAdV-7.     

Current Status of Human Papillomavirus-Related Head and Neck Cancer: From Viral Genome to Patient Care

Virologica Sinica - Human papillomavirus (HPV) infection identified as a definitive human carcinogen is increasingly being recognized for its role in carcinogenesis of human cancers. Up to...     

4种河鲀全基因组微卫星分布特征分析

本研究利用MISA软件对四种河鲀全基因组中的微卫星进行筛选并分析.结果如下:在红鳍东方鲀(Takifugu rubripes)(391.49 Mb)、菊黄东方鲀(T.flavidus)(366.29 Mb)、双斑东方鲀(T.bimaculatus)(371.68 Mb)及黑青斑河鲀(Tetraodon nigroviridis)(342.40 Mb)全基因组中,分别筛选出142 885个、135 009个、147 549个和179 703个完整型微卫星.相对丰度分别为365个/Mb,369个/Mb,397个/Mb和525个/Mb.微卫星总长度分别为2 876 322 bp,2 689 710 bp,3 140 445 bp 和3 615 069 bp,分别占基因组序列总长度的0.73％,0.73％,0.84％和1.06％.在1～6个不同碱基重复类型完整型微卫星中,四种河鲀的6种碱基类型数目排序是一致的.均是单碱基重复数目最多,然后依次是二碱基、三碱基、四碱基、五碱基和六碱基.其中AC,A,C,AG,AGG,AT,AAT和AAC是四种河鲀共有的常见核心重复类别.东方鲀属(Takifugu)三种河鲀基因组微卫星分布特征极为相似,分析红鳍东方鲀和双斑东方鲀的遗传距离可能更为接近.鲀属(Tetraodon)黑青斑河鲀与其他三种东方鲀属河鲀除部分微卫星特征相似外,在微卫星总数、微卫星相对丰度和密度、部分碱基类型数目及类别方面和东方鲀属差距较大.这可能与两属鱼类地理分布及进行滑动复制的碱基组成有关,推测东方鲀属和鲀属基因组可能具有独特的进化机制.本研究为多种河鲀基因组特征分析、多种河鲀微卫星引物设计、不同属种河鲀遗传距离及亲缘关系的探究等奠定了基础.     

基于转录组分析酸枣仁斯皮诺素生物合成途径的相关基因

采用转录组测序技术分析酸枣仁(Ziziphi spinosae semen)不同发育时期基因表达差异,识别酸枣仁黄酮生物合成途径的相关基因,为进一步分析酸枣仁中黄酮类成分生物合成相关酶基因提供研究基础.以3个不同生长发育时期的酸枣仁样本为供试材料,采用Illumina Hiseq 4000进行转录组测序,并从头拼接,对转录本进行功能注释和差异性分析.经StringTie软件组装拼接得到74472个转录本,其中有26.83％在NR、Swiss-Prot、Pfam、GO、KOG、KEGG数据库中得到注释;代谢通路分析结果发现,在酸枣仁转录组中与黄酮类合成途径相关的11条差异表达基因可能编码斯皮诺素合成途径的一些酶类.酸枣仁中黄酮类成分斯皮诺素相关转录本信息为阐明斯皮诺素在生长期的积累提供重要依据,为提高酸枣仁品质研究提供参考.     

Evolution and diversity of axon guidance Robo receptor family genes

The diversity of axon guidance (AG) receptors reflects gains in complexity of the animal nervous system during evolution. Members of the Roundabout (Robo) family of receptors interact with Slit proteins and play important roles in many developmental processes, including AG and neural crest cell migration. There are four members of the Robo gene family. However, the evolutionary history of Robo family genes remain obscure. We analyzed the distribution of Robo family members in metazoan species ranging in complexity from hydras to humans. We undertook a phylogenetic analysis in metazoans, synteny analysis, and ancestral chromosome mapping in vertebrates, and detected selection pressure and functional divergence among four mammalian Robo paralogs. Based on our analysis, we proposed that the ancestral Robo gene could have undergone a tandem duplication in the vertebrate ancestor; then one round of whole genome duplication events occurred before the divergence of ancestral lamprey and gnathostome, generating four paralogs in early vertebrates. Robo4 paralog underwent segmental loss in the following evolutionary process. Our results showed that Robo3 paralog is under more powerful purifying selection pressure compared with other three paralogs, which could correlate with its unique expression pattern and function. Furthermore, we found four sites under positive selection pressure on the Ig1‐2 domains of Robo4 that might interfere with its binding to Slits ligand. Diverge analysis at the amino acid level showed that Robo4 paralog have relatively greater functional diversifications than other Robo paralogs. This coincides with the fact that Robo4 predominantly functions in vascular endothelial cells but not the nervous system.     

鳖甲煎丸通过LncRNA-mRNA顺式调控抑制肝癌细胞

为了研究鳖甲煎丸抑制肝癌细胞过程中lncRNA表达谱的变化及lncRNA-mRNA顺式调控在其中的机制,本研究通过CCK8方法检测鳖甲煎丸作用于SMMC-7721细胞后的增殖活性变化,经全细胞转录组学分析lncRNA的表达和特征后构建LncRNA-mRNA顺式调控网络.结果表明鳖甲煎丸含药血清作用肝癌细胞株后其增殖活性受到抑制.全细胞转录组学分析找到差异表达的172个LncRNA.构建lncRNA-mRNA顺式调控网络,对调控基因进行生存分析发现,SCRN1、PLEKHA1、HNRNPM、TMEM107、ETNK1、ISG20L2的表达与肝细胞癌患者生存率显著负相关(P＜0.05).因此得出结论,LncRNA参与鳖甲煎丸抑制肝癌细胞增殖的过程,LncRNA-mRNA顺式调控是其分子机制之一.     

楝酰胺类化合物的抗肿瘤活性探究进展

楝酰胺类化合物存在于楝属植物中,因其独特的化学结构而具有杀虫、抗炎及抗癌的活性.目前研究发现,楝酰胺类化合物对多种癌症如肺癌、肾癌、胰腺癌、恶性外周神经鞘瘤等都具有独特的细胞凋亡作用,而对正常细胞无毒害作用.楝酰胺类化合物抗肿瘤的机制主要有:抑制癌细胞翻译起始、调控细胞周期、诱导肿瘤细胞凋亡、抑制细胞增殖、降低药物细胞毒性等.因此,楝酰胺及其衍生物作为潜在抗癌药物也有极大的应用前景,成为近年来的研究热点.本综述总结了楝属植物中的次生代谢产物-楝酰胺类化合物的发现过程、结构特征和抗癌活性,重点阐述了其在癌症中的作用机制.以期为楝酰胺类化合物的进一步研究和开发利用提供理论依据和研究思路,并对楝酰胺类化合物的应用前景进行了展望.     

Application of germ-free NOD-scid IL2rgnull mice as a humanized model for tumor microbiome precision medicine

正In 2013, tumor immunotherapy topped the list of the top ten scientific breakthroughs(Couzin-Frankel, 2013), and it was widely used in the treatment of lung cancer, kidney cancer,and melanoma(Routy et al., 2018). However, the response rate of patients to tumor immunotherapy varies, and usually,only a small percentage of patients respond well to treatment(Sambi et al., 2019).