Geminivirus replication: genetic and biochemical characterization of Rep protein function, a review

Replication of the single-stranded DNA genome of plant geminiviruses follows a rolling circle mechanism. It strictly depends on a 'replication initiator protein' (Rep) which is the sole viral protein essential for replication. Rep protein catalyzes multiple reactions during the reproductive cycle of the virus. Here we summarize the recent advances of in vivo and in vitro analyses of the various Rep protein activities in a model for replication initiation and termination. In addition, the position of the geminivirus Rep protein within a general context of bacterial and mammalian replication initiator proteins is discussed.