昆虫学报 ›› 2021, Vol. 64 ›› Issue (1): 61-69.doi: 10.16380/j.kcxb.2021.01.007

• 研究论文 • 上一篇    下一篇

家蚕抗真菌因子BmSPI39对球孢白僵菌入侵的表达响应

李游山1,2, 路庆君1, 杨玺1, 张杰1, 罗竹星1, 夏庆友3, 赵萍3,*   

  1. (1. 陕西理工大学生物科学与工程学院, 陕西汉中 723001; 2. 陕西理工大学, 陕南秦巴山区生物资源综合开发协同创新中心, 陕西汉中 723001; 3. 西南大学前沿交叉学科研究院, 生物学研究中心, 重庆 400715)科学与工程学院, 陕西汉中 723001; 2. 陕西理工大学, 陕南秦巴山区生物资源综合开发协同创新中心, 陕西汉中 723001; 3. 西南大学前沿交叉学科研究院, 生物学研究中心, 重庆 400715)
  • 出版日期:2021-01-20 发布日期:2021-02-18

Expression of the fungal-resistance factor BmSPI39 in Bombyx mori in response to Beauveria bassiana invasion

LI You-Shan1, 2, LU Qing-Jun1, YANG Xi1, ZHANG Jie1, LUO Zhu-Xing1, XIA Qing-You3, ZHAO Ping3,*   

  1.  (1. College of Biological Science and Engineering, Shaanxi University of Technology, Hanzhong, Shaanxi 723001, China; 2. Collaborative Innovation Center for Comprehensive Development of Qinba Biological Resources, Shaanxi University of Technology, Hanzhong, Shaanxi 723001, China; 3. Biological Science Research Center, Academy for Advanced Interdisciplinary Studies, Southwest University, Chongqing 400715, China)
  • Online:2021-01-20 Published:2021-02-18

摘要: 【目的】制备家蚕Bombyx mori抗真菌因子BmSPI39的多克隆抗体,分析BmSPI39对球孢白僵菌Beauveria bassiana入侵的表达响应。【方法】利用原核表达和固定化镍离子亲和层析技术获得高纯度的BmSPI39重组蛋白,利用胶内活性染色检测重组蛋白BmSPI39对枯草杆菌Bacillus subtilis蛋白酶A的抑制活性;利用重组蛋白BmSPI39,通过免疫新西兰大白兔制备BmSPI39的多克隆抗体。基于家蚕开放性数据库SilkDB 3.0,分析BmSPI39在4龄第3天至化蛹后1 d家蚕免疫相关组织体壁、中肠和脂肪体中的时空表达特征。利用制备的BmSPI39抗体通过Western blot分析感染球孢白僵菌不同时间后家蚕幼虫和蛹体壁中BmSPI39应答球孢白僵菌入侵的表达响应。【结果】胶内活性染色结果显示,重组BmSPI39蛋白能够强烈抑制枯草杆菌蛋白酶A的活性。酶联免疫吸附结果显示,BmSPI39抗血清的抗体效价达1∶128 000。Western blot和胶内活性染色结果显示,纯化后的BmSPI39抗体能够有效结合不同多聚体化状态下的BmSPI39抗原蛋白。BmSPI39表达数据的热图分析显示,BmSPI39在游走期和预蛹期的家蚕体壁中有表达,在预蛹期的脂肪体中的表达量较高,但在各发育阶段的中肠中均不表达。Western blot分析结果表明,家蚕幼虫体壁中的BmSPI39的表达在感染球孢白僵菌后84 h上调表达,108和120 h下调表达。【结论】本研究成功制备了BmSPI39的多克隆抗体。BmSPI39蛋白的表达能够响应球孢白僵菌入侵,可能参与蛹期家蚕抵御真菌入侵的过程。

关键词: 家蚕, 球孢白僵菌, 抗真菌因子, 多克隆抗体, 游走期, 蛹期, 体壁

Abstract: 【Aim】 To prepare polyclonal antibody of the fungal-resistance factor BmSPI39 in Bombyx mori and to analyze its expression in response to Beauveria bassiana invasion. 【Methods】 Prokaryotic expression and immobilized nickel ion affinity chromatography were used to obtain the highly-purified recombinant BmSPI39 protein. The inhibitory activity of the recombinant BmSPI39 protein to Bacillus subtilis protease A was detected by in-gel activity staining. Polyclonal antibodies to BmSPI39 were prepared by immunizing New Zealand white rabbit with the recombinant BmSPI39 protein. Based on the open database SilkDB 3.0 of B. mori, the spatiotemporal expression characteristics of BmSPI39 in the immune-related tissues, integument, midgut and fat body, of B. mori from the day-3 4th instar larva to 1 day-old pupa were analyzed. And the expression of BmSPI39 in response to B. bassiana invasion in the integument of B. mori larvae and pupae at different time after B. bassiana infection was assayed using the prepared BmSPI39 antibodies by Western blot. 【Results】 The results of in-gel activity staining showed that the recombinant BmSPI39 protein could strongly inhibit the activity of subtilisin A. Enzyme-linked immunosorbent assay (ELISA) showed that the antibody titer of BmSPI39 antiserum reached 1∶128 000. The results of Western blot and in-gel activity staining showed that the purified BmSPI39 antibody could effectively bind to the BmSPI39 antigen protein in different multimerization states. The heat map analysis of the expression data of BmSPI39 showed that BmSPI39 was expressed in the integument of B. mori at the wandering stage and the pre-pupal stage, with a higher expression level in the fat body at the pre-pupal stage, but not in the midgut at all the tested developmental stages. The results of Western blot showed that the expression of BmSPI39 in the integument of B. mori larvae was up-regulated at 84 h and down-regulated at 108 and 120 h after B. bassiana infection. 【Conclusion】 Polyclonal antibody to BmSPI39 was successfully prepared in this study. The expression of BmSPI39 protein can respond to B. bassiana invasion and may be involved in the process of resisting fungal invasion in the pupal stage of B. mori.

Key words:  Bombyx mori, Beauveria bassiana, fungal-resistance factor, polyclonal antibody; wandering stage, pupal stage, integument