Dynamic subcellular distribution of begomoviral nuclear shuttle and movement proteins

The Abutilon mosaic virus (AbMV) encodes a nuclear shuttle protein (NSP), and a movement protein (MP) which cooperatively accomplish viral DNA transport through the plant. Subcellular distribution patterns of fluorescent protein-tagged NSP and MP were tracked in Nicotiana benthamiana leaves in presence or absence of an AbMV infection using light microscopy. NSP was located within the nucleus and associated with early endosomes in the presence of MP. MP appeared at the plasma membrane, plasmodesmata and in motile vesicles, trafficking along the endoplasmic reticulum in an actin-dependent manner. MP and NSP did not co-localize and employed separate cellular pathways. Correspondingly, Förster resonance energy transfer analysis did not support physical interaction between NSP and MP. Time lapse movies illustrate the cellular dynamics of both proteins on their way around the nucleus and to the cell periphery and provide a first hint for the nuclear egress of NSP complexes. [Display omitted] •Movement protein (MP) localizes at plasma membrane, plasmodesmata and vesicles.•MP-vesicles traffic along the ER in an actin-dependent pathway.•MP shows interaction with itself, but not with nuclear shuttle protein (NSP).•NSP arises in presence of MP outside the nucleus and in early endosomal vesicles.•NSP and MP mediating geminivirus movement localize spatially-temporally different.