title: The 32 kDa subunit of replication protein A (RPA) participates in the DNA replication of Mung bean yellow mosaic India virus (MYMIV) by interacting with the viral Rep protein.
abstract: Mung bean yellow mosaic India virus (MYMIV) is a member of genus begomoviridae and its genome comprises of bipartite (two components, namely DNA-A and DNA-B), single-stranded, circular DNA of about 2.7 kb. During rolling circle replication (RCR) of the DNA, the stability of the genome and maintenance of the stem-loop structure of the replication origin is crucial. Hence the role of host single-stranded DNA-binding protein, Replication protein A (RPA), in the RCR of MYMIV was examined. Two RPA subunits, namely the RPA70 kDa and RPA32 kDa, were isolated from pea and their roles were validated in a yeast system in which MYMIV DNA replication has been modelled. Here, we present evidences that only the RPA32 kDa subunit directly interacted with the carboxy terminus of MYMIV-Rep both in vitro as well as in yeast two-hybrid system. RPA32 modulated the functions of Rep by enhancing its ATPase and down regulating its nicking and closing activities. The possible role of these modulations in the context of viral DNA replication has been discussed. Finally, we showed the positive involvement of RPA32 in transient replication of the plasmid DNA bearing MYMIV replication origin using an in planta based assay.
authors.affiliation: Plant Molecular Biology Group, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi-110 067, India.
authors.forename: Dharmendra Kumar
authors.initials: DK
authors.lastname: Singh
authors.forename: Mohammad Nurul
authors.initials: MN
authors.lastname: Islam
authors.forename: Nirupam Roy
authors.initials: NR
authors.lastname: Choudhury
authors.forename: Sumona
authors.initials: S
authors.lastname: Karjee
authors.forename: Sunil Kumar
authors.initials: SK
authors.lastname: Mukherjee
mesh_terms: D001681:Biological Assay; D004265:DNA Helicases / Q000378:metabolism*; D004261:DNA Replication; D004279:DNA, Viral / Q000096:biosynthesis*; D004268:DNA-Binding Proteins / Q000378:metabolism*; D017791:Geminiviridae / Q000235:genetics*; D005816:Genetic Complementation Test; D009154:Mutation; D018532:Pisum sativum / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D021122:Protein Subunits / Q000235:genetics / Q000378:metabolism; D051716:Replication Protein A / Q000235:genetics / Q000378:metabolism*; D014026:Nicotiana / Q000821:virology; D015534:Trans-Activators / Q000378:metabolism*; D020798:Two-Hybrid System Techniques; D014764:Viral Proteins / Q000378:metabolism*; D015003:Yeasts / Q000235:genetics
chemical_list: D004279:DNA, Viral; D004268:DNA-Binding Proteins; D010940:Plant Proteins; D021122:Protein Subunits; D051716:Replication Protein A; D015534:Trans-Activators; D014764:Viral Proteins; C045264:replication initiator protein; D004265:DNA Helicases