title: Tubule-guided cell-to-cell movement of a plant virus requires class XI myosin motors.
abstract: Cell-to-cell movement of plant viruses occurs via plasmodesmata (PD), organelles that evolved to facilitate intercellular communications. Viral movement proteins (MP) modify PD to allow passage of the virus particles or nucleoproteins. This passage occurs via several distinct mechanisms one of which is MP-dependent formation of the tubules that traverse PD and provide a conduit for virion translocation. The MP of tubule-forming viruses including Grapevine fanleaf virus (GFLV) recruit the plant PD receptors called Plasmodesmata Located Proteins (PDLP) to mediate tubule assembly and virus movement. Here we show that PDLP1 is transported to PD through a specific route within the secretory pathway in a myosin-dependent manner. This transport relies primarily on the class XI myosins XI-K and XI-2. Inactivation of these myosins using dominant negative inhibition results in mislocalization of PDLP and MP and suppression of GFLV movement. We also found that the proper targeting of specific markers of the Golgi apparatus, the plasma membrane, PD, lipid raft subdomains within the plasma membrane, and the tonoplast was not affected by myosin XI-K inhibition. However, the normal tonoplast dynamics required myosin XI-K activity. These results reveal a new pathway of the myosin-dependent protein trafficking to PD that is hijacked by GFLV to promote tubule-guided transport of this virus between plant cells.
authors: Institut de Biologie Moléculaire des Plantes du CNRS, Université de Strasbourg, Strasbourg, France.
authors: Khalid
authors: K
authors: Amari
authors: Alexander
authors: A
authors: Lerich
authors: Corinne
authors: C
authors: Schmitt-Keichinger
authors: Valerian V
authors: VV
authors: Dolja
authors: Christophe
authors: C
authors: Ritzenthaler
mesh_terms: D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000494:pharmacology; D006056:Golgi Apparatus / Q000187:drug effects / Q000502:physiology / Q000821:virology; D054884:Host-Pathogen Interactions; D021962:Membrane Microdomains / Q000187:drug effects / Q000821:virology; D008870:Microtubules / Q000187:drug effects / Q000502:physiology / Q000821:virology; D009218:Myosins / Q000037:antagonists & inhibitors / Q000378:metabolism*; D017860:Nepovirus / Q000187:drug effects / Q000472:pathogenicity / Q000502:physiology*; D053830:Plant Viral Movement Proteins / Q000502:physiology*; D021381:Protein Transport / Q000187:drug effects / Q000502:physiology; D053778:Thiazolidines / Q000494:pharmacology; D017361:Viral Nonstructural Proteins
chemical_list: D019086:Bridged Bicyclo Compounds, Heterocyclic; D053830:Plant Viral Movement Proteins; D053778:Thiazolidines; D017361:Viral Nonstructural Proteins; D009218:Myosins; C037068:latrunculin B