Interaction between the flagellum of Candidatus Liberibacter asiaticus and the vitellogenin-like protein of Diaphorina citri significantly influences C Las titer

Tao Peng; Yingzhe Yuan; Aijun Huang; Jun He; Shimin Fu; Shuo Duan; Long Yi; Chenyang Yuan; Huizhu Yuan; Xuefeng Wang; Changyong Zhou

doi:10.3389/fmicb.2023.1119619

Interaction between the flagellum of Candidatus Liberibacter asiaticus and the vitellogenin-like protein of Diaphorina citri significantly influences C Las titer

Front Microbiol. 2023 Apr 18:14:1119619. doi: 10.3389/fmicb.2023.1119619. eCollection 2023.

Authors

Tao Peng¹, Yingzhe Yuan¹, Aijun Huang², Jun He¹, Shimin Fu¹, Shuo Duan², Long Yi², Chenyang Yuan³, Huizhu Yuan⁴, Xuefeng Wang¹, Changyong Zhou¹

Affiliations

¹ National Citrus Engineering Research Center, Citrus Research Institute, Southwest University, Chongqing, China.
² National Navel Orange Engineering Research Center, Gannan Normal University, Ganzhou, China.
³ Key Laboratory of Entomology and Pest Control Engineering, College of Plant Protection, Southwest University, Chongqing, China.
⁴ Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Ministry of Agriculture and Rural Affairs, Beijing, China.

Abstract

Huanglongbing (HLB) is a global devastating citrus disease that is mainly caused by "Candidatus Liberibacter asiaticus" (CLas). It is mostly transmitted by the insect Asian citrus psyllid (ACP, Diaphorina citri) in a persistent and proliferative manner. CLas traverses multiple barriers to complete an infection cycle and is likely involved in multiple interactions with D. citri. However, the protein-protein interactions between CLas and D. citri are largely unknown. Here, we report on a vitellogenin-like protein (Vg_VWD) in D. citri that interacts with a CLas flagellum (flaA) protein. We found that Vg_VWD was upregulated in CLas-infected D. citri. Silencing of Vg_VWD in D. citri via RNAi silencing significantly increased the CLas titer, suggesting that Vg_VWD plays an important role in the CLas-D. citri interaction. Agrobacterium-mediated transient expression assays indicated that Vg_VWD inhibits BAX- and INF1-triggered necrosis and suppresses the callose deposition induced by flaA in Nicotiana benthamiana. These findings provide new insights into the molecular interaction between CLas and D. citri.

Keywords: CLas; Diaphorina citri; Huanglongbing; flagella; vitellogenin.