Characterization and functional analysis of a myeloid differentiation factor 88 in Ostrinia furnacalis Guen acute accent ee larvae infected by Bacillus thuringiensis
Characterization and functional analysis of a myeloid differentiation factor 88 in Ostrinia furnacalis Guen acute accent ee larvae infected by Bacillus thuringiensis
复制标题
苏云金芽孢杆菌感染亚洲玉米螟幼虫骨髓分化因子 88 的特征和功能分析
DOI：
10.1016/j.dci.2022.104489
复制
发表时间：
2022-07-04
影响因子：
2.9
通讯作者：
Feng, Congjing
中科院分区：
文献类型：
--
作者：
Alradi, Mohamed F.;Lu, Shiqi;Feng, Congjing
Myeloid differentiation factor 88 (MyD88) is a pivotal adapter protein involved in activating nuclear factor NF kappa B of the Toll pathway in insect innate immunity. MyD88 has been extensively studied in vertebrates and Drosophila. However, the information ascribed to MyD88 in Lepidoptera is scarce. In the present study, an Ostrinia furnacalis MyD88 (OfMyD88) cDNA was cloned and functionally characterized (GenBank accession no. MN906311). The complete cDNA sequence of OfMyD88 is 804 bp, and contains a 630 bp open reading frame encoding 209 amino acid residues. OfMyD88 has the death domain (DD), an intermediate domain, and the Toll/ interleukin 1 receptor (TIR) domain. OfMyD88 was widely expressed in immune-related tissues such as hemocytes, fat body, midgut, and integument, with the highest expression level in hemocytes, and the lowest expression level in integument. To clarify the immune function of MyD88, O. furnacalis larvae were challenged with Bacillus thuringiensis (Bt) through feeding. Bt oral infection had significantly up-regulated the expression of OfMyD88 and immune genes, including PPO2 (prophenoloxidase 2), Attacin, Gloverin, Cecropin, Moricin, GRP3 (beta-1, 3-Glucan recognition protein 3), and Lysozyme, and increased the activities of PO and lysozyme in hemolymph of O. furnacalis larvae. Knockdown of OfMyD88 by RNA interference suppressed the expression levels of immune related genes, but not PPO2 in the larvae orally infected with Bt, suggesting that OfMyD88 is involved in defending against Bt invasion through the Toll signaling pathway, but does not affect the PPO expression in O. furnacalis larvae.
