title: The Potyviridae P1a leader protease contributes to host range specificity.
abstract: The P1a protein of the ipomovirus Cucumber vein yellowing virus is one of the self-cleavage serine proteases present in Potyviridae family members. P1a is located at the N-terminal end of the viral polyprotein, and is closely related to potyviral P1 protease. For its proteolytic activity, P1a requires a still unknown host factor; this might be linked to involvement in host specificity. Here we built a series of constructs and chimeric viruses to help elucidate the role of P1a cleavage in host range definition. We demonstrate that host-dependent separation of P1a from the remainder of the polyprotein is essential for suppressing RNA silencing defenses and for efficient viral infection. These findings support the role of viral proteases as important determinants in host adaptation.
authors.affiliation: Departamento de Genética Molecular de Plantas, Centro Nacional de Biotecnología (CNB-CSIC), Darwin 3, 28049 Madrid, Spain.
authors.forename: Hongying
authors.initials: H
authors.lastname: Shan
authors.affiliation: Departamento de Genética Molecular de Plantas, Centro Nacional de Biotecnología (CNB-CSIC), Darwin 3, 28049 Madrid, Spain. Electronic address: fpasin@cnb.csic.es.
authors.forename: Fabio
authors.initials: F
authors.lastname: Pasin
authors.affiliation: Departamento de Genética Molecular de Plantas, Centro Nacional de Biotecnología (CNB-CSIC), Darwin 3, 28049 Madrid, Spain.
authors.forename: Adrián
authors.initials: A
authors.lastname: Valli
authors.affiliation: Departamento de Genética Molecular de Plantas, Centro Nacional de Biotecnología (CNB-CSIC), Darwin 3, 28049 Madrid, Spain.
authors.forename: Carla
authors.initials: C
authors.lastname: Castillo
authors.affiliation: Departamento de Genética Molecular de Plantas, Centro Nacional de Biotecnología (CNB-CSIC), Darwin 3, 28049 Madrid, Spain.
authors.forename: Charukesi
authors.initials: C
authors.lastname: Rajulu
authors.affiliation: Departamento de Genética Molecular de Plantas, Centro Nacional de Biotecnología (CNB-CSIC), Darwin 3, 28049 Madrid, Spain.
authors.forename: Alberto
authors.initials: A
authors.lastname: Carbonell
authors.affiliation: Departamento de Genética Molecular de Plantas, Centro Nacional de Biotecnología (CNB-CSIC), Darwin 3, 28049 Madrid, Spain.
authors.forename: Carmen
authors.initials: C
authors.lastname: Simón-Mateo
authors.affiliation: Departamento de Genética Molecular de Plantas, Centro Nacional de Biotecnología (CNB-CSIC), Darwin 3, 28049 Madrid, Spain. Electronic address: jagarcia@cnb.csic.es.
authors.forename: Juan Antonio
authors.initials: JA
authors.lastname: García
authors.affiliation: Departamento de Genética Molecular de Plantas, Centro Nacional de Biotecnología (CNB-CSIC), Darwin 3, 28049 Madrid, Spain. Electronic address: brodamilans@cnb.csic.es.
authors.forename: Bernardo
authors.initials: B
authors.lastname: Rodamilans
mesh_terms: D020816:Amino Acid Motifs; D018553:Cucumis sativus / Q000235:genetics / Q000821:virology; D058507:Host Specificity; D054884:Host-Pathogen Interactions; D010935:Plant Diseases / Q000235:genetics / Q000821:virology*; D020815:Polyproteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D019176:Potyviridae / Q000737:chemistry / Q000201:enzymology* / Q000235:genetics / Q000502:physiology*; D011499:Protein Processing, Post-Translational; D034622:RNA Interference; D057057:Serine Proteases / Q000235:genetics / Q000378:metabolism*; D014026:Nicotiana / Q000235:genetics / Q000821:virology; D014764:Viral Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
chemical_list: D020815:Polyproteins; D014764:Viral Proteins; D057057:Serine Proteases
keywords: Cucumber vein yellowing virus; Host range; P1 proteases; Plum pox virus; Potyviridae; RNA silencing suppression