Plant tip growth has been recognized as an actin-based cellular process requiring targeted exocytosis and
compensatory endocytosis to occur at the growth cone. However, the identity of subcellular compartments involved in
polarized membrane trafficking pathways remains enigmatic in plants. Here we characterize endosomal compartments
in tip-growing root hair cells. We demonstrate their presence at the growing tip and differential distribution upon
cessation of tip growth. We also show that both the presence of endosomes as well as their rapid movements within the
tip region depends on an intact actin cytoskeleton and involves actin polymerization. In conclusion, actin-propelled
endosomal motility is tightly linked to the polar tip growth of root hairs.
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