ABA homeostasis and long-distance translocation are redundantly regulated by ABCG ABA importers.

Journal Article (Journal Article)

The effects of abscisic acid (ABA) on plant growth, development, and response to the environment depend on local ABA concentrations. Here, we show that in Arabidopsis , ABA homeostasis is regulated by two previously unknown ABA transporters. Adenosine triphosphate–binding cassette subfamily G member 17 (ABCG17) and ABCG18 are localized to the plasma membranes of leaf mesophyll and cortex cells to redundantly promote ABA import, leading to conjugated inactive ABA sinks, thus restricting stomatal closure. ABCG17 and ABCG18 double knockdown revealed that the transporters encoded by these genes not only limit stomatal aperture size, conductance, and transpiration while increasing water use efficiency but also control ABA translocation from the shoot to the root to regulate lateral root emergence. Under abiotic stress conditions, ABCG17 and ABCG18 are transcriptionally repressed, promoting active ABA movement and response. The transport mechanism mediated by ABCG17 and ABCG18 allows plants to maintain ABA homeostasis under normal growth conditions.

Full Text

Duke Authors

Cited Authors

  • Zhang, Y; Kilambi, HV; Liu, J; Bar, H; Lazary, S; Egbaria, A; Ripper, D; Charrier, L; Belew, ZM; Wulff, N; Damodaran, S; Nour-Eldin, HH; Aharoni, A; Ragni, L; Strader, L; Sade, N; Weinstain, R; Geisler, M; Shani, E

Published Date

  • October 2021

Published In

Volume / Issue

  • 7 / 43

Start / End Page

  • eabf6069 -

PubMed ID

  • 34669479

Pubmed Central ID

  • PMC8528425

Electronic International Standard Serial Number (EISSN)

  • 2375-2548

International Standard Serial Number (ISSN)

  • 2375-2548

Digital Object Identifier (DOI)

  • 10.1126/sciadv.abf6069


  • eng