Overexpression of an auxilin-like gene (F9E10.5) can suppress Al uptake in roots of Arabidopsis

J Exp Bot. 2007;58(3):497-506. doi: 10.1093/jxb/erl221. Epub 2006 Dec 5.

Abstract

Plants resistant to aluminium (Al) stress were isolated from Arabidopsis thaliana enhancer-tagged mutant lines. Compared with the parental Col-7 control line, one of the resistant candidates, #355-2, showed a higher expression of the F9E10.5 gene (At1g75100) on chromosome 1, a lower Al content in whole roots, and a shorter root hair length (approximately 30%). Both Al influx and associated oxidative stress occurred in root hairs, as well as in root tips of Col-7; however, they were seen only in root tips of #355-2. Transgenic plants overexpressing the F9E10.5 gene showed a slightly higher Al resistance than their parental control line (Ler). The F9E10.5 gene encodes an auxilin-like protein related to the clathrin-uncoating process in endocytosis. Microscopic observation indicated that both Al ion influx and endocytosis activity were lower in root hair cells of the #355-2 line than in those of Col-7. These results suggested that overexpression of this auxilin-like protein inhibits endocytosis in root hair cells by a disturbance of the transport system as in animal cells shown previously. It was also suggested that a part of the Al influx occurred via endocytosis in root hair cells in Arabidopsis. The Al resistance in the #355-2 line may therefore be due to a lower Al uptake via endocytosis in the root hair region.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aluminum / metabolism*
  • Arabidopsis / anatomy & histology
  • Arabidopsis / genetics
  • Arabidopsis / metabolism*
  • Arabidopsis Proteins / genetics
  • Arabidopsis Proteins / metabolism*
  • Auxilins / genetics
  • Auxilins / metabolism*
  • Endocytosis / genetics
  • Ion Transport / genetics
  • Plant Roots / anatomy & histology
  • Plant Roots / genetics
  • Plant Roots / metabolism
  • Plants, Genetically Modified / metabolism

Substances

  • Arabidopsis Proteins
  • Auxilins
  • F9E10.5 protein, Arabidopsis
  • Aluminum