The miR184-3p targets neuron-specific ecdysone inducible protein 78 to promote rice black streaked dwarf virus propagation in its planthopper vector

Pest Manag Sci. 2024 Apr 27. doi: 10.1002/ps.8150. Online ahead of print.

Abstract

Background: MicroRNAs (miRNAs) are non-coding RNAs that play a pivotal role in antiviral infection. The miR184-3p has been identified to promote rice black streaked dwarf virus (RBSDV) infection in vector Laodelphax striatellus, whether it targets other genes of L. striatellus to modulate RBSDV propagation remains unknown.

Results: We first analyzed the expression profiles of miR184-3p and its role in regulating RBSDV infection in L. striatellus. Then the candidate genes expression of miR184-3p were systemically analyzed with gain and loss function of miR184-3p, and the interaction of candidate gene, ecdysone inducible protein 78 (Eip78) with miR184-3p was verified by dual luciferase reporter assay. We found Eip78 is evolutionary conserved among agricultural pests and predominantly expressed in the central nervous system (CNS) of L. striatellus. Knockdown of Eip78 effectively increased RBSDV propagation and transmission. Blockade with Eip78 antibody or injection with Eip78 protein could significantly regulate RBSDV infection. Further analysis revealed that knockdown of Eip78 specifically suppresses RBSDV infection in the head part but not in the body part of L. striatellus. Besides, knockdown of ecdysone receptor (EcR) notably restricted Eip78 expression and increased RBSDV accumulation in L. striatellus.

Conclusions: Taken together, we identified a novel target gene of miR184-3p, Eip78, a member of the ecdysone signaling pathway, and revealed the anti-RBSDV role of Eip78 in the CNS of L. striatellus. These results shed light on the interaction mechanisms of miRNAs, virus and ecdysone signaling pathway in insect vector. © 2024 Society of Chemical Industry.

Keywords: antiviral mechanism; central nervous system; ecdysone inducible protein 78; ecdysone receptor; miR184‐3p; rice black streak dwarf virus.