Discovery of novel thrips vector proteins that bind to the viral attachment protein of the plant bunyavirus, tomato spotted wilt virus

Abstract

16The plant-pathogenic virus, tomato spotted wilt virus (TSWV), encodes a structural 17 glycoprotein (G N ) that, like with other bunyavirus/vector interactions, serves a role in viral 18 attachment and possibly entry into arthropod vector host cells. It is well documented that 19Frankliniella occidentalis is one of seven competent thrips vectors of TSWV transmission to 20 plant hosts, however, the insect molecules that interact with viral proteins, such as G N , during 21 infection and dissemination in thrips vector tissues are unknown. The goals of this project 22 Importance Statement 37 Thrips-transmitted viruses cause devastating losses to numerous food crops worldwide. For 38 negative-sense RNA viruses that infect plants, the arthropod serves as a host as well by 39 supporting virus replication in specific tissues and organs of the vector. The goal of this work 40 was to identify vector/host proteins that bind directly to the viral attachment protein and thus 41 may play a role in the infection cycle in the insect. Using the model plant bunyavirus, tomato 42 spotted wilt virus (TSWV), and the most efficient thrips vector, we identified and validated 43 six TSWV-interacting proteins from Frankliniella occidentalis first instar larvae. Two 44 proteins, an endocuticle structural glycoprotein and cyclophilin, were able to interact directly 45 with the TSWV attachment protein, G N, in insect cells. The TSWV G N -interacting proteins 46 3 provide new targets for disrupting the virus-vector interaction and could be putative 47 determinants of vector competence. 48 49Vector-borne diseases caused by animal-and plant-infecting viruses are some of the 50 most important medical, veterinary, and agricultural problems worldwide (1, 2). The majority 51 of viruses infecting plants and animals are transmitted by arthropods. Understanding the viral 52 and arthropod determinants of vector competence is important for basic knowledge of virus-53 vector interactions and development of new interdiction strategies to control disease. 54Significant progress has been made towards identification of viral determinants of 55 transmission, but the interacting molecules in vectors remain largely elusive. For negative-56 sense RNA viruses, vector factors that mediate the transmission process have not been well 57 characterized. 58Bunyavirales is the largest order of negative-sense RNA viruses; twelve families are 59 described (http://www.ictvonline.org/virustaxonomy.asp). The Bunyavirales contains plant 60 and insect vector-infecting viruses that make up the Family Tospoviridae (3-5). Within this 61 family, there are eighteen species and several unassigned viruses that most likely will be 62 classified as unequivocal members of the Orthotospovirus genus. Tomato spotted wilt 63 orthotospovirus is the type species within this genus and has been best characterized in terms 64 of viral host range, genome organization and protein functions (6, 7). 65 Tomato spotted wilt virus (TSWV) infects both monocotyledonous and dicotyledonous 66 plants enc...

Comprehensive analysis of lysine lactylation in Frankliniella occidentalis

“…Besides, it interacts with the glycoprotein of TSWV and affects TSWV infection of F. occidentalis. (Badillo-Vargas et al, 2019). We also found another protein cyclophilin (GenBank accession: MH884760), with five modification sites (K71, K89, K122, K181, and K191) (Figure 7B).…”

“…TSWV synthesizes a structural glycoprotein (GN) for viral attachment and viral expression in arthropod vector host cells. A previous study reported that two proteins, cyclophilin and endocuticle structural glycoprotein (EndoCP-GN), interact with the GN of F. occidentalis (Badillo-Vargas et al, 2019). We found that these two proteins have multiple Klac sites, suggesting that lactylation may play an important role in mediating the transmission of TSWV by F. occidentalis.…”

“…We also found another protein cyclophilin (GenBank accession: MH884760), with five modification sites (K71, K89, K122, K181, and K191) (Figure 7B). This protein is involved in metabolic activities and is closely related to TSWV-GN interaction (Badillo-Vargas et al, 2019). Cyclophilin has been shown to prevent viral infections and play a vital role in the transmission of grain yellow dwarf virus via aphids as a carrier (Liu et al, 2018;von Hahn and Ciesek, 2015;Tamborindeguy et al, 2013).…”

Looking Through the Lens of 'Omics Technologies: Insights Into the Transmission of Insect Vector-borne Plant Viruses

“…In an exciting preprint by Badillo-Vargas et al (2018), the first ever tospovirus-binding thrips proteins were identified. Using 2-D gel overlay assays coupled to MS, the authors identified six thrips proteins from the first instar larvae that bind TSWV: the endocuticle structural glycoprotein endoCP-V, the cuticular protein CP-V, cyclophilin, enolase, mitochondrial ATP synthase α (mAT-Pase), and the endocuticle structural glycoprotein endoCP-G N (Fig.…”

Examination of the quantitative relationship between proteome- and transcriptome-level responses in larval guts ofFrankliniella occidentalisinfected with an orthotospovirus

“…As such, it is imperative to investigate both transcriptional and translational events and/or outcomes in order to Han and Rotenberg, proteome of tospovirus-infected thrips guts of vector species (Brault et al, 2010;Geng et al, 2018;Han & Rotenberg, 2021;Zhao et al, 2016). Previously, we reported the first thrips gut transcriptome of F. occidentalis larvae in response to TSWV infection (Han & Rotenberg, 2021), and provided several candidate biomarkers of infection at a stage when TSWV is known to enter and invade the epithelium of the anterior midgut of L1 (i.e., limited to a few cells) (Ullman et al, 2012;Badillo-Vargas et al, 2019), and when virus titer is at its lowest during the transmission cycle (Badillo-Vargas et al, 2012, Rotenberg andWhitfield, 2018;Han and Rotenberg, 2021). It was the early L1 stagethree hours after a 24-hour exposure period on TSWV-infected plant tissue -that exhibited a relatively larger transcriptome-wide response to infection compared to the L2 stage (48 hours post exposure), when virus titers in the gut had increased 3-fold (Han and Rotenberg, 2021), and virus has disseminated and invaded other regions of the midgut (Montero-Astúa et al, 2016a).…”