Zhang Ping, Zhang Yonglei, Yang ShiYi, Hong YuTing, Du Ying, Hu ZhangQi, Tang Jing, Wang Suisui, Feng Fan, Li Bin
Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing 210023, China.
Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing 210023, China.
Int J Biol Macromol. 2022 May 1;206:422-434. doi: 10.1016/j.ijbiomac.2022.02.134. Epub 2022 Mar 1.
C-type lectins (CTLs) play vital roles in invertebrates' innate immunity. Six CTL-X type lectins are identified in Tribolium castaneum. However, their functions and regulating mechanisms remain elusive. Here, TcCTL12, one CTL-X, was identified and cloned from T. castaneum. Spatiotemporal expression profiling revealed that TcCTL12 highly expressed in late pupa and early adult of T. castaneum in comparison with other developmental stages, and exhibited the highest expression level in the haemolymph and central nervous system (CNS). Then, the expression of TcCTL12 was remarkably induced by the stimulation of Escherichia coli and Staphylococcus aureus. Moreover, the recombinant protein TcCTL12 could bind pathogen-associated molecular patterns (PAMPs) including LPS and PGN, and displayed agglutinative activity to both Gram-positive and Gram-negative bacteria in a calcium-dependent manner in vitro. Furthermore, RNAi of TcCTL12 caused T. castaneum pupation and eclosion defected. The abnormal pupa thinned their epidermal, and appeared the abnormal development of muscle cell compared with the control group. Additionally, depletion of TcCTL12 resulted in reducing fertility of offspring and affected their fecundity. In sum, these results indicated that TcCTL12 had extensive functions in the regulation of development in T. castaneum, in addition to the immune response. It further expanded insights into CTL functions in insects.
C型凝集素（CTLs）在无脊椎动物的先天免疫中发挥着至关重要的作用。在赤拟谷盗中鉴定出了六种CTL-X型凝集素。然而，它们的功能和调控机制仍然不清楚。在此，从赤拟谷盗中鉴定并克隆了一种CTL-X型凝集素TcCTL12。时空表达谱分析表明，与其他发育阶段相比，TcCTL12在赤拟谷盗的蛹后期和成虫早期高表达，并且在血淋巴和中枢神经系统（CNS）中表现出最高的表达水平。然后，大肠杆菌和金黄色葡萄球菌的刺激显著诱导了TcCTL12的表达。此外，重组蛋白TcCTL12可以结合包括脂多糖（LPS）和肽聚糖（PGN）在内的病原体相关分子模式（PAMPs），并在体外以钙依赖的方式对革兰氏阳性菌和革兰氏阴性菌都表现出凝集活性。此外，对TcCTL12进行RNA干扰导致赤拟谷盗化蛹和羽化缺陷。与对照组相比，异常蛹的表皮变薄，肌肉细胞出现异常发育。此外，敲除TcCTL12导致后代繁殖力降低并影响其生育力。总之，这些结果表明，TcCTL12除了免疫反应外，在赤拟谷盗发育调控中具有广泛的功能。它进一步拓展了对昆虫中CTL功能的认识。
