Shahzad Toufeeq, Zhan Ming-Yue, Yang Pei-Jin, Yu Xiao-Qiang, Rao Xiang-Jun
School of Plant Protection, Anhui Agricultural University, Hefei, China.
Division of Molecular Biology and Biochemistry, School of Biological Sciences, University of Missouri-Kansas City, Kansas City, MO, USA.
Arch Insect Biochem Physiol. 2017 Jul;95(3). doi: 10.1002/arch.21391. Epub 2017 Jun 15.
C-type lectins (CTLs) play a variety of roles in plants and animals. They are involved in animal development, pathogen recognition, and the activation of immune responses. CTLs carry one or more non-catalytic carbohydrate-recognition domains (CRDs) to bind specific carbohydrates reversibly. Here, we report the molecular cloning and functional analysis of a single-CRD CTL, named C-type lectin-S2 (BmCTL-S2) from the domesticated silkmoth Bombyx mori (Lepidoptera: Bombycidae). The ORF of CTL-S2 is 666 bp, which encodes a putative protein of 221 amino acids. BmCTL-S2 is expressed in a variety of immune-related tissues, including hemocytes and fat body among others. BmCTL-S2 mRNA level in the midgut and the fat body was significantly increased by bacterial challenges. The recombinant protein (rBmCTL-S2) bound different bacterial cell wall components and bacterial cells. rBmCTL-S2 also inhibited the growth of Bacillus subtilis and Staphylococcus aureus. Taken together, we infer that BmCTL-S2 is a pattern-recognition receptor with antibacterial activities.
C型凝集素（CTLs）在植物和动物中发挥着多种作用。它们参与动物发育、病原体识别以及免疫反应的激活。CTLs携带一个或多个非催化性碳水化合物识别结构域（CRDs）以可逆地结合特定碳水化合物。在此，我们报道了一种来自家蚕（鳞翅目：蚕蛾科）的单CRD CTL的分子克隆及功能分析，该CTL名为C型凝集素-S2（BmCTL-S2）。CTL-S2的开放阅读框为666 bp，编码一个推定的221个氨基酸的蛋白质。BmCTL-S2在多种免疫相关组织中表达，包括血细胞和脂肪体等。细菌刺激后，中肠和脂肪体中的BmCTL-S2 mRNA水平显著升高。重组蛋白（rBmCTL-S2）能结合不同的细菌细胞壁成分和细菌细胞。rBmCTL-S2还能抑制枯草芽孢杆菌和金黄色葡萄球菌的生长。综上所述，我们推断BmCTL-S2是一种具有抗菌活性的模式识别受体。
