Tobacco mosaic virus movement protein associates with the cytoskeleton in tobacco cells

• Published in: The Plant cell 1995-12, Vol.7 (12), p.2101-2114
• Main Authors: McLean, B. Gail, Zupan, John, Zambryski, Patricia C.
• Format: Article
• Language: English
• Subjects: Actins; Actins - isolation & purification; Actins - metabolism; Antibodies; binding proteins; cell structure; Cloning, Molecular; Cytoskeleton; Cytoskeleton - metabolism; Cytoskeleton - ultrastructure; Escherichia coli; estructura celular; glicoproteinas; globulinas; globuline; globulins; glycoproteine; glycoproteins; Microfilaments; Microtubules; Models, Structural; Nicotiana - metabolism; Nicotiana - ultrastructure; Nicotiana - virology; nicotiana tabacum; Plant cells; Plant Viral Movement Proteins; plant viruses; Plants, Toxic; Plasmids; Plasmodesmata; Protein Binding; proteinas; proteinas aglutinantes; proteine; proteine de liaison; proteins; Protoplasts; Recombinant Fusion Proteins - biosynthesis; Recombinant Fusion Proteins - isolation & purification; Recombinant Fusion Proteins - metabolism; RNA; RNA, Viral - metabolism; structure cellulaire; tobacco mosaic tobamovirus; Tobacco Mosaic Virus - physiology; tobamovirus del mosaico del tabaco; tobamovirus mosaique du tabac; Tubulin - isolation & purification; Tubulin - metabolism; Viral Proteins - biosynthesis; Viral Proteins - isolation & purification; Viral Proteins - metabolism; virus de las plantas; virus des vegetaux; Viruses
• ISSN: 1040-4651; 1532-298X
• DOI: 10.1105/tpc.7.12.2101

Tobacco mosaic virus movement protein P30 complexes with genomic viral RNA for transport through plasmodesmata, the plant intercellular connections. Although most research with P30 focuses on its targeting to and gating of plasmodesmata, the mechanisms of P30 intracellular movement to plasmodesmata have not been defined. To examine P30 intracellular localization, we used tobacco protoplasts, which lack plasmodesmata, for transfection with plasmids carrying P30 coding sequences under a constitutive promoter and for infection with tobacco mosaic virus particles. In both systems, P30 appears as filaments that colocalize primarily with microtubules. To a lesser extent, P30 filaments colocalize with actin filaments, and in vitro experiments suggested that P30 can bind directly to actin and tubulin. This association of P30 with cytoskeletal elements may play a critical role in intracellular transport of the P30-viral RNA complex through the cytoplasm to and possibly through plasmodesmata.