文章摘要
厚壳贻贝MyD88-4基因的生物学特性及其对沙氏弧菌的免疫应答
Identification of MyD88-4 in Mytilus coruscus and expression changes in response to Vibrio chagasii challenge
投稿时间:2019-01-06  修订日期:2019-03-18
DOI:
中文关键词: 厚壳贻贝  髓样分化因子88(MyD88)  基因克隆  组织表达  弧菌感染
英文关键词: Mytilus coruscus  myeloid differentiation factor 88 (MyD88)  gene cloning  tissue expression  Vibrio infection
基金项目:国家重点基础研究发展计划
作者单位E-mail
梁箫 上海海洋大学 国家海洋生物科学国际联合研究中心 x-liang@shou.edu.cn 
刘钰珠 上海海洋大学 国家海洋生物科学国际联合研究中心  
陈珂 上海海洋大学 国家海洋生物科学国际联合研究中心  
李一峰 上海海洋大学 国家海洋生物科学国际联合研究中心  
杨金龙 上海海洋大学 国家海洋生物科学国际联合研究中心 jlyang@shou.edu.cn 
摘要点击次数: 520
全文下载次数: 0
中文摘要:
      为理解髓样分化因子88(myeloid differentiation factor 88)基因的生物学特性以及对细菌胁迫的响应,本研究克隆了厚壳贻贝MyD88基因(命名为McMyD88-4)cDNA 全长序列,其全长为3930 bp,开放阅读框2607 bp,编码868个氨基酸。其中,13-109的氨基酸序列为死亡结构域(Death domain,DD),347-481的氨基酸序列为TIR(Toll/interleukin-1 receptor)结构域,其中TIR结构域包含3个高度保守的的区域Box 1、Box 2和Box3;McMyD88-4蛋白的空间结构包含6个α螺旋(α-helix)和4个β折叠(β-sheet)。同源性分析显示,McMyD88-4蛋白序列与太平洋牡蛎(Crassostrea gigas)MyD88最相似,其一致性和相似性分别为60 %和77%;其次,与虾夷扇贝(Mizuhopecten yessoensis)、海湾扇贝(Argopecten irradians)和菲律宾蛤仔(Ruditapes philippinarum)相似度较高,其一致性和相似性分别为40%-51%和58%-67 %。系统进化树结果显示,McMyD88-4先与太平洋牡蛎和扇贝聚为一支,然后与果蝇聚为一支,脊椎动物单独聚为一支。实时荧光定量PCR(RT-qPCR)检测发现,McMyD88-4基因在厚壳贻贝各组织和器官中均有表达,其中在外套膜和鳃中的表达量最高,而血细胞中表达量最低。厚壳贻贝经沙氏弧菌(Vibrio chagasii)感染后,McMyD88-4基因表达量在免疫相关组织中急剧上升,在3 h和6 h达到峰值,且在消化腺中的上调水平明显高于鳃和外套膜。研究表明,McMyD88-4在厚壳贻贝抵御外界病原体,尤其是弧菌感染方面发挥重要作用。
英文摘要:
      Myeloid differentiation factor 88 (MyD88) is a crucial adaptor protein in the toll-like receptor (TLR) signaling pathway and plays an important role in signal transmission. In this study, the full-length cDNA sequence of a MyD88 gene from Mytilus coruscus (McMyD88-4) was cloned. Its cDNA sequence is 3930 bp, with a 2607 bp open reading frame encoding a protein of 868 amino acids. Amino acids at position of 13-109 are the dead domain, and amino acids at position of 347-481 are the Toll/interleukin-1 receptor (TIR) domain, which contains three highly conserved regions Box 1, Box 2 and Box3. The three-dimensional structure of McMyD88-4 contains six α-helix and four β-sheets. According to the comparison with known MyD88 amino acids sequence, the putative protein of McMyD88-4 was most similar to that of Crassostrea gigas, with the identity and similarity of 60 % and 77 % respectively. Then it was more similar to Mizuhopecten yessoensis, Argopecten irradians, Ruditapes philippinarum, with 40 %-51 % of identity and 58 %-67 % of similarity. Phylogenetic tree showed that McMyD88-4 of M. coruscus firstly clustered with Pacific oysters and scallops, and then with Drosophila, while vertebrates formed a separate cluster. RT-qPCR revealed that McMyD88-4 was expressed in all tissues and organs examined. The highest expression was found in the mantle and gill, while the lowest expression found in haemocytes. After infection by Vibrio chagasii, the expression of McMyD88-4 was up-regulated sharply in immune-related tissues, and reached the peak at 3 h and 6 h, and the up-regulation level in digestive gland was significantly higher than that in gill and mantle. Our results showed that McMyD88-4 plays an important role during the immune response of M. coruscus against external pathogens, especially Vibrio infections.
HTML     下载PDF阅读器
关闭

手机扫一扫看