title: Geminivirus DNA replication and cell cycle interactions.
abstract: The Geminiviridae family includes a large number of viruses that infect plants and have a unique geminate virion particle, a single-stranded genome of approximately 2.6-3.0 kb, and replicate through a rolling-circle mechanism. Since they encode for just a few proteins (4-6 depending on the members that belong to four different genera), a rich variety of interactions has evolved between viral proteins and host factors to develop the virus replicative cycle. Among them, we have been particularly interested so far: (i). in the interference with cell cycle regulatory proteins of the retinoblastoma-related (RBR)/E2F pathway and (ii). in the interaction with host DNA replication factors necessary for the assembly of a functional replication complex at the viral origin of DNA replication during the rolling-circle stage. Yeast two-hybrid assays revealed that wheat dwarf virus RepA protein, but nor Rep protein, interacts with plant RBR protein. Interestingly, deletion of the C-terminal domain of Rep confers the truncated protein the ability to interact with RBR, suggesting that this domain may hinder the LXCXE RBR-binding motif. Secondary structure predictions support such a possibility.
authors.affiliation: Centro de Biologia Molecular "Severo Ochoa", Consejo Superior de Investigaciones Cientificas and Universidad Autonoma de Madrid, Cantoblanco, 28049 Madrid, Spain. cgutierrez@cbm.uam.es
authors.forename: Crisanto
authors.initials: C
authors.lastname: Gutierrez
authors.forename: Elena
authors.initials: E
authors.lastname: Ramirez-Parra
authors.forename: M
authors.initials: M
authors.lastname: Mar Castellano
authors.forename: Andres P
authors.initials: AP
authors.lastname: Sanz-Burgos
authors.forename: Alejandro
authors.initials: A
authors.lastname: Luque
authors.forename: Riccardo
authors.initials: R
authors.lastname: Missich
mesh_terms: D000595:Amino Acid Sequence; D002453:Cell Cycle / Q000502:physiology; D018797:Cell Cycle Proteins / Q000378:metabolism; D004261:DNA Replication / Q000502:physiology*; D017791:Geminiviridae / Q000235:genetics / Q000254:growth & development / Q000378:metabolism / Q000502:physiology*; D016679:Genome, Viral; D008969:Molecular Sequence Data; D018741:Replication Origin; D016160:Retinoblastoma Protein / Q000378:metabolism; D020798:Two-Hybrid System Techniques; D014779:Virus Replication / Q000235:genetics*
chemical_list: D018797:Cell Cycle Proteins; D016160:Retinoblastoma Protein