Systematic Identification and Functional Analysis of Circular RNAs During Rice Black-Streaked Dwarf Virus Infection in the Laodelphax striatellus (Fallén) Midgut

Abstract

Circular RNAs (circRNAs) are endogenous RNAs that have critical regulatory roles in numerous biological processes. However, it remains largely unknown whether circRNAs are induced in response to plant virus infection in the insect vector of the virus as well as whether the circRNAs regulate virus infection. Rice black-streaked dwarf virus (RBSDV) is transmitted by Laodelphax striatellus (Fallén) in a persistent propagative manner and causes severe losses in East Asian countries. To explore the expression and function of circRNAs in the regulation of virus infection, we determined the circRNA expression profile in RBSDV-free or RBSDV-infected L. striatellus midgut tissues by RNA-Seq. A total of 2,523 circRNAs were identified, of which thirteen circRNAs were differentially expressed after RBSDV infection. The functions of these differentially circRNAs were predicted by GO and KEGG pathway analyses. The expression changes of five differentially expressed circRNAs and eight parental genes were validated by RT-qPCR. The circRNAs-microRNAs (miRNAs) interaction networks were analyzed and two miRNAs, which were predicted to bind circRNAs, were differentially expressed after virus infection. CircRNA2030 was up-regulated after RBSDV infection in L. striatellus midgut. Knockdown of circRNA2030 by RNA interference inhibited the expression of its predicted parental gene phospholipid-transporting ATPase (PTA) and enhanced RBSDV infection in L. striatellus. However, none of the six miRNAs predicting to bind circRNA2030 was up-regulated after circRNA2030 knockdown. The results suggested that circRNA2030 might affect RBSDV infection via regulating PTA. Our results reveal the expression profile of circRNAs in L. striatellus midgut and provide new insight into the roles of circRNAs in virus-insect vector interaction.

Risk assessment and resistance inheritance of triflumezopyrim resistance in Laodelphax striatellus

“…The small brown planthopper, Laodelphax striatellus (Fallén) (Hemiptera: Delphacidae), is an important short‐distance migratory pest 1 . In addition to stabbing and sucking the base of rice by adults and nymphs, they also transmit viruses such as rice black‐streaked dwarf virus 2 . At present, the control of L. striatellus mainly depends on chemical insecticides, but this has resulted in varying degrees of resistance to imidacloprid, chlorpyrifos, deltamethrin and other pesticides 3–5 …”

“…1 In addition to stabbing and sucking the base of rice by adults and nymphs, they also transmit viruses such as rice black-streaked dwarf virus. 2 At present, the control of L. striatellus mainly depends on chemical insecticides, but this has resulted in varying degrees of resistance to imidacloprid, chlorpyrifos, deltamethrin and other pesticides. [3][4][5] Triflumezopyrim, a novel intermediate-ion pyrimidine insecticide from Corteva Agriscience, binds to the orthosteric site of the nicotinic acetylcholine receptor (nAChR), making the insects lethargic and poisoned, and has been gradually applied to the field control of insects having biting and sucking mouthparts such as rice planthopper and leafhopper.…”

MicroRNA‐315‐5p promotes rice black‐streaked dwarf virus infection by targeting a melatonin receptor in the small brown planthopper

“…For example, host circular RNA2030 inhibits RBSDV infection in SBPH via regulating its parental gene phospholipidtransporting ATPase. 15 In Aedes aegypti, long non-coding RNA-1317 is involved in the host anti-viral defense during dengue virus serotype 2 (DENV-2) infection. 29 Inhibition of lncRNA MSTRG15394 promotes RBSDV accumulation in SBPH midgut.…”

“…10 Our previous research showed that RBSDV infection resulted in a significant decrease of miR-315-5p at mRNA level. 15 However, the biological function of -miR-315-5p in plant virus-insect vector interaction is unclear.…”

The Potential Biological Roles of Circular RNAs in the Immune Systems of Insects to Pathogen Invasion

“…Further experiments, such as the luciferase reporter assay for the validation of the interaction between circ_0001432 and its target miRNAs and knockdown or overexpression of circ_0001432 in vivo and in vitro, are needed to illustrate the function of circ_0001432 [ 87 ]. Furthermore, Zhang et al [ 89 ] discovered 444 novel circRNAs from the BmN cells. Of these 75 circRNAs, some have been shown to be differentially expressed during BmNPV infection.…”