TRANSPORTER OF IBA1 Links Auxin and Cytokinin to Influence Root Architecture.

Journal Article (Journal Article)

Developmental processes that control root system architecture are critical for soil exploration by plants, allowing for uptake of water and nutrients. Conversion of the auxin precursor indole-3-butyric acid (IBA) to active auxin (indole-3-acetic acid; IAA) modulates lateral root formation. However, mechanisms governing IBA-to-IAA conversion have yet to be elucidated. We identified TRANSPORTER OF IBA1 (TOB1) as a vacuolar IBA transporter that limits lateral root formation. Moreover, TOB1, which is transcriptionally regulated by the phytohormone cytokinin, is necessary for the ability of cytokinin to exert inhibitory effects on lateral root production. The increased production of lateral roots in tob1 mutants, TOB1 transport of IBA into the vacuole, and cytokinin-regulated TOB1 expression provide a mechanism linking cytokinin signaling and IBA contribution to the auxin pool to tune root system architecture.

Full Text

Duke Authors

Cited Authors

  • Michniewicz, M; Ho, C-H; Enders, TA; Floro, E; Damodaran, S; Gunther, LK; Powers, SK; Frick, EM; Topp, CN; Frommer, WB; Strader, LC

Published Date

  • September 2019

Published In

Volume / Issue

  • 50 / 5

Start / End Page

  • 599 - 609.e4

PubMed ID

  • 31327740

Pubmed Central ID

  • PMC6736748

Electronic International Standard Serial Number (EISSN)

  • 1878-1551

International Standard Serial Number (ISSN)

  • 1534-5807

Digital Object Identifier (DOI)

  • 10.1016/j.devcel.2019.06.010


  • eng