open access

https://hdl.handle.net/2115/59503

Polar localization and endocytic degradation of a boron transporter, BOR1, is dependent on specific tyrosine residues

英語

endocytosis

2012-01

Taylor & Francis

Plant Signaling & Behavior

7(1)

46-49

Boron (B) is essential for plants, but is toxic in excess. Plants have to strictly regulate the uptake and translocation of B. In Arabidopsis thaliana root cells, a boric acid channel, NIP5;1, and a boric acid/borate exporter, BOR1, localize to the outer (facing soil) and inner plasma membrane domains, respectively, under B limitation. The opposite polar localizations of the importer and exporter would enable plant roots to transport B efficiently towards the xylem. In addition, accumulation of the B transporters is controlled by B conditions. When plants are shifted from low to high B conditions, NIP5;1 transcript accumulation is down-regulated through mRNA degradation. The BOR1 protein is transported to the trans-Golgi network/early endosome and multivesicular body and finally degraded in the vacuole. We have recently shown that both the polar localization and the endocytic degradation of BOR1 are controlled by at least two tyrosine residues in a large loop located in the cytosol. We also showed that ubiquitination is required for the endocytic degradation of BOR1. Here, we analyzed possible involvement of an additional tyrosine residue (Y414) in the loop region and discuss the pathway of the BOR1 trafficking for polar localization and endocytic degradation of BOR1.

学術雑誌論文

Accepted Manuscript

1559-2324