Processing (P)-bodies are cytoplasmic RNA protein aggregates responsible for the 
storage, degradation, and quality control of translationally repressed messenger 
RNAs in eukaryotic cells. In mammals, P-body-related RNA and protein exchanges 
are actomyosin dependent, whereas P-body movement requires intact microtubules. 
In contrast, in plants, P-body motility is actin based. In this study, we show 
the direct interaction of the P-body core component DECAPPING PROTEIN1 (DCP1) 
with the tails of different unconventional myosins in Arabidopsis (Arabidopsis 
thaliana). By performing coexpression studies with AtDCP1, dominant-negative 
myosin fragments, as well as functional full-length myosin XI-K, the association 
of P-bodies and myosins was analyzed in detail. Finally, the combination of 
mutant analyses and characterization of P-body movement patterns showed that 
myosin XI-K is essential for fast and directed P-body transport. Together, our 
data indicate that P-body movement in plants is governed by myosin XI members 
through direct binding to AtDCP1 rather than through an adapter protein, as 
known for membrane-coated organelles. Interspecies and intraspecies interaction 
approaches with mammalian and yeast protein homologs suggest that this mechanism 
is evolutionarily conserved among eukaryotes.