Participates in the transport of viral genome to neighboring plant cells directly through plasmodesmata, without any budding (PubMed:18353960). TGBp2 and TGBp3 are necessary for intracellular delivery of TGBp1-containing vRNPs to plasmodesmata (PubMed:19570874). Can gate plasmodesmata and increase their size exclusion limit (PubMed:19570874). To a lesser extent than TGB3, induces host actin cytoskeleton network thickening, which probably plays a major role in virus cell-to-cell movement (PubMed:25288925). Interacts with movement protein TGB3 (PubMed:18353960). TGB1-TGB3-TGB2 complex formation is enhanced by ATP hydrolysis (PubMed:32730331). Probably localizes to plasmodesmata-associated membrane compartments called peripheral membrane bodies (PMBs) (Probable). Associates with host actin filaments, possibly for the intracellular transport to the plasmodesmata (PubMed:25288925). The viral replication sites are located at the host chloroplast membrane (By similarity). This protein is translated as a fusion protein by episodic readthrough of a termination codon. Readthrough of the terminator codon TGA occurs between the codons for Gly-131 and Ser-133, thereby producing TGB2' minor translational readthrough protein. The genome of this virus consists of three linear, positive, single-stranded RNAs encapsidated in separate virions designated RNA-alpha, RNA-beta and RNA-gamma. Three proteins (alpha-A, beta-A and gamma-A) are translated directly from these genomic RNAs and the remaining proteins encoded on RNA-beta (beta-B, beta-C and beta-D) and RNA-gamma (gamma-B) are expressed via three subgenomic messenger RNAs. Belongs to the virgaviridae/benyvirus TGB2 movement protein family.