A single rep protein initiates replication of multiple genome components of faba bean necrotic yellows virus, a single-stranded DNA virus of plants.

ABSTRACT: Faba bean necrotic yellows virus (FBNYV) belongs to the nanoviruses, plant viruses whose genome consists of multiple circular single-stranded DNA components. Eleven distinct DNAs, 5 of which encode different replication initiator (Rep) proteins, have been identified in two FBNYV isolates. Origin-specific DNA cleavage and nucleotidyl transfer activities were shown for Rep1 and Rep2 proteins in vitro, and their essential tyrosine residues that catalyze these reactions were identified by site-directed mutagenesis. In addition, we showed that Rep1 and Rep2 proteins hydrolyze ATP, and by changing the key lysine residue in the proteins' nucleoside triphosphate binding sites, demonstrated that this ATPase activity is essential for multiplication of virus DNA in vivo. Each of the five FBNYV Rep pr

SUBMITTER: Timchenko T 

PROVIDER: S-EPMC113070 | biostudies-literature | 1999 Dec

REPOSITORIES: biostudies-literature