Strong activator of the late viral genes promoters. Enhances the expression of the capsid protein and nuclear shuttle protein. Acts as a suppressor of RNA-mediated gene silencing, also known as post-transcriptional gene silencing (PTGS), a mechanism of plant viral defense that limits the accumulation of viral RNAs. Suppresses the host RNA silencing by inhibiting adenosine kinase 2 (ADK2), a kinase involved in a general methylation pathway. Also suppresses the host basal defense by interacting with and inhibiting SNF1 kinase, a key regulator of cell metabolism implicated in innate antiviral defense. Determines pathogenicity (By similarity). Monomer. Homodimer. Homooligomer. Self-interaction correlates with nuclear localization and efficient activation of transcription. Monomers suppress local silencing by interacting with and inactivating host adenosine kinase 2 (ADK2) in the cytoplasm. Interacts with and inhibits host SNF1 kinase. Binds to ssDNA (By similarity). The phosphorylated form appears to accumulate almost exclusively in the nucleus, whereas the non-phosphorylated form is found in both nucleus and cytoplasm. The zinc finger and the transactivation region are involved in PTGS suppression. Phosphorylated at Ser-109 by A.thaliana KIN10. Belongs to the geminiviridae transcriptional activator protein family.