QUICK SEARCH:   [advanced] Author: Keyword(s):
Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents

First published online April 10, 2009
doi: 10.1242/10.1242/dev.025932

This Article Figures Only Full Text Full Text (PDF) Supplementary Material Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Ploense, S. E. Articles by Reed, J. W. Search for Related Content PubMed Articles by Ploense, S. E. Articles by Reed, J. W. Social Bookmarking                         What's this?

A gain-of-function mutation in IAA18 alters Arabidopsis embryonic apical patterning

Department of Biology, University of North Carolina at Chapel Hill, Coker Hall, Chapel Hill, NC 27599, USA.

^* Author for correspondence (e-mail: jreed{at}email.unc.edu)

Accepted 27 February 2009

Lateral organ emergence in plant embryos and meristems depends on spatially coordinated auxin transport and auxin response. Here, we report the gain-of-function iaa18-1 mutation in Arabidopsis, which stabilizes the Aux/IAA protein IAA18 and causes aberrant cotyledon placement in embryos. IAA18 was expressed in the apical domain of globular stage embryos, and in the shoot apical meristem and adaxial domain of cotyledons of heart stage embryos. Mutant globular embryos had asymmetric PIN1:GFP expression in the apical domain, indicating that IAA18-1 disrupts auxin transport. Genetic interactions among iaa18-1, loss-of-function mutations in ARF (Auxin response factor) genes and ARF-overexpressing constructs suggest that IAA18-1 inhibits activity of MP/ARF5 and other ARF proteins in the apical domain. The iaa18-1 mutation also increased the frequency of rootless seedlings in mutant backgrounds in which auxin regulation of basal pole development was affected. These results indicate that apical patterning requires Aux/IAA protein turnover, and that apical domain auxin response also influences root formation.

Key words: Auxin, Aux/IAA, Phyllotaxy, Embryo

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter    What's this?

This article has been cited by other articles:

				B. Moller and D. Weijers Auxin Control of Embryo Patterning Cold Spring Harb Perspect Biol, November 1, 2009; 1(5): a001545 - a001545. [Abstract] [Full Text] [PDF]