Zhang K, Li C, Weng X, Su J, Shen L, Pan G, Long D, Zhao A, Cui H
State Key Laboratory of Silkworm Genome Biology, The Institute of Sericulture and Systems Biology, Southwest University, Chongqing, China.
College of Biotechnology, Southwest University, Chongqing, China.
Insect Mol Biol. 2018 Apr;27(2):133-142. doi: 10.1111/imb.12360. Epub 2017 Nov 13.
Haemocytes play crucial roles in insect metabolism, metamorphosis, and innate immunity. As a model of lepidopteran insects, the silkworm is a useful model to study the functions of both haematopoiesis and haemocytes. Tissue-specific promoters are excellent tools for genetic manipulation and are widely used in fundamental biological research. Herein, two haemocyte-specific genes, Integrin β2 and Integrin β3, were confirmed. Promoter activities of Integrin β2 and Integrin β3 were evaluated by genetic manipulation. Quantitative real-time PCR and western blotting suggested that both promoters can drive enhanced green fluorescent protein (EGFP) specifically expressed in haemocytes. Further evidence clearly demonstrated that the transgenic silkworm exhibited a high level of EGFP signal in plasmatocytes, but not in other detected haemocyte types. Moreover, EGFP fluorescence signals were observed in the haematopoietic organ of both transgenic strains. Thus, two promoters that enable plasmatocytes to express genes of interest were confirmed in our study. It is expected that the results of this study will facilitate advances in our understanding of insect haematopoiesis and immunity in the silkworm, Bombyx mori.
血细胞在昆虫的新陈代谢、变态发育和先天免疫中发挥着关键作用。作为鳞翅目昆虫的模型，家蚕是研究造血作用和血细胞功能的有用模型。组织特异性启动子是基因操作的优秀工具，广泛应用于基础生物学研究。在此，确认了两个血细胞特异性基因，整合素β2和整合素β3。通过基因操作评估了整合素β2和整合素β3的启动子活性。定量实时PCR和蛋白质免疫印迹表明，这两个启动子都能驱动增强型绿色荧光蛋白（EGFP）在血细胞中特异性表达。进一步的证据清楚地表明，转基因家蚕在浆血细胞中表现出高水平的EGFP信号，但在其他检测到的血细胞类型中未表现出该信号。此外，在两个转基因品系的造血器官中都观察到了EGFP荧光信号。因此，我们的研究确认了两个能够使浆血细胞表达感兴趣基因的启动子。预计本研究结果将有助于推动我们对家蚕（Bombyx mori）昆虫造血作用和免疫的理解。
