A gain-of-function mutation in IAA16 confers reduced responses to auxin and abscisic acid and impedes plant growth and fertility.

Journal Article (Journal Article)

Auxin regulates many aspects of plant development, in part, through degradation of the Aux/IAA family of transcriptional repressors. Consequently, stabilizing mutations in several Aux/IAA proteins confer reduced auxin responsiveness. However, of the 29 apparent Aux/IAA proteins in Arabidopsis thaliana, fewer than half have roles established through mutant analysis. We identified iaa16-1, a dominant gain-of-function mutation in IAA16 (At3g04730), in a novel screen for reduced root responsiveness to abscisic acid. The iaa16-1 mutation also confers dramatically reduced auxin responses in a variety of assays, markedly restricts growth of adult plants, and abolishes fertility when homozygous. We compared iaa16-1 phenotypes with those of dominant mutants defective in the closely related IAA7/AXR2, IAA14/SLR, and IAA17/AXR3, along with the more distantly related IAA28, and found overlapping but distinct patterns of developmental defects. The identification and characterization of iaa16-1 provides a fuller understanding of the IAA7/IAA14/IAA16/IAA17 clade of Aux/IAA proteins and the diverse roles of these repressors in hormone response and plant development.

Full Text

Duke Authors

Cited Authors

  • Rinaldi, MA; Liu, J; Enders, TA; Bartel, B; Strader, LC

Published Date

  • July 2012

Published In

Volume / Issue

  • 79 / 4-5

Start / End Page

  • 359 - 373

PubMed ID

  • 22580954

Pubmed Central ID

  • PMC3382072

Electronic International Standard Serial Number (EISSN)

  • 1573-5028

International Standard Serial Number (ISSN)

  • 0167-4412

Digital Object Identifier (DOI)

  • 10.1007/s11103-012-9917-y


  • eng