A conserved motif in three viral movement proteins from different genera is required for host factor recruitment and cell-to-cell movement

Abstract

Due to their minimal genomes, plant viruses are forced to hijack specific cellular pathways to ensure host colonization, a condition that most frequently involves physical interaction between viral and host proteins. Among putative viral interactors are the movement proteins, responsible for plasmodesma gating and genome binding during viral transport. Two of them, DGBp1 and DGBp2, are required for alpha-, beta- and gammacarmovirus cell-to-cell movement, but the number of DGBp-host interactors identified at present is limited. By using two different approaches, yeast two-hybrid and bimolecular fluorescence complementation assays, we found three Arabidopsis factors, eIF3g1, RPP3A and WRKY36, interacting with DGBp1s from each genus mentioned above. eIF3g1 and RPP3A are mainly involved in protein translation initiation and elongation phases, respectively, while WRKY36 belongs to WRKY transcription factor family, important regulators of many defence responses. These host proteins are not expected to be associated with viral movement, but knocking out WRKY36 or silencing either RPP3A or eIF3g1 negatively affected Arabidopsis infection by Turnip crinkle virus. A highly conserved FNF motif at DGBp1 C-terminus was required for protein-protein interaction and cell-to-cell movement, suggesting an important biological role.

The immune Rysto receptor recognizes a broadly conserved feature of potyviral coat proteins

“…Many viral proteins execute multiple roles in the replication process, as well as in the suppression of plant defences (Leisner and Schoelz, 2018). In many cases, a combination of structural features creates defined motifs exerting particular functions (i.e., RNA binding), conserved in proteins from virtually all organisms (Navarro et al, 2020;Zamora et al, 2015). Such structure-function relationships are yet to be elucidated for many R-Avr interactions.…”

The grape MYB24 mediates the coordination of light-induced terpene and flavonol accumulation in response to berry anthocyanin sunscreen depletion

“…Bimolecular fluorescence complementation (BiFC) assay. The BiFC assays were performed in Agrobacterium-infiltrated tobacco (Nicotiana benthamiana) leaves as described (111). The four TFs (VviMYB24, AtMYC5, VviMYC2, and VviMYC1) were amplified and cloned to two binary vectors (35S::NtGFP and 35S::CtGFP).…”

Viruses Infecting Trees and Herbs That Produce Edible Fleshy Fruits with a Prominent Value in the Global Market: An Evolutionary Perspective

“…Virus infections can be classified as systemic or local. Local infection refers to confinement of virus within and nearby the site of infection, whereas the systemic infection is progressive and starts from the site of infection and then spreads throughout the whole plant using the host vasculature [114,115]. The infected plant can exhibit a variety of symptoms, highly characteristic ones being the induction of colorful patterns (mosaic, chlorosis, necrosis, local necrotic, or chlorotic spots) and distortions (twisting, curling) on leaves, as well as malformation on the branches and discoloration and streaks on the flower petals [60].…”