Abstract
In Arabidopsis thaliana, 57 Rab GTPases are encoded in its genome, 26 of which are classified into Rab11 group (RabA1-RabA6). On the other hand, yeast and animals possess a few Rab11 genes. This implies that Rab11 has evolved in a unique way in plants. However, precise function of plant Rab11 remains largely unknown. To reveal the function of plant Rab11, we analyzed subcellular localization of 9 members belonging to RabA1 subgroup (RabA1a-RabA1i). We generated transgenic plants expressing GFP/Venus-tagged RabA1s, which are driven by their own promoters. Detailed observation of GFP-RabA1e revealed that it localizes on dynamically moving dotty compartments, which partially overlap with Syp42 and Syp43-labelled TGN. We also found that RabA1e-compartments accumulate in the tip region of growing root hairs. These results suggest that RabA1e functions in secretion from the TGN to the PM for the tip growth of root hairs.
