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

First published online 28 January 2009
doi: 10.1242/dev.031625

This Article Figures Only Full Text Full Text (PDF) Supplementary Material All Versions of this Article: dev.031625v1 136/5/823    most recent Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Related articles in Development Similar articles in this journal Similar articles in PubMed 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 Berger, Y. Articles by Ori, N. Search for Related Content PubMed PubMed Citation Articles by Berger, Y. Articles by Ori, N. Social Bookmarking                         What's this?

The NAC-domain transcription factor GOBLET specifies leaflet boundaries in compound tomato leaves

Yael Berger^1,*, Smadar Harpaz-Saad^1,*, Arnon Brand^1,*, Hadas Melnik¹, Neti Sirding¹, John Paul Alvarez², Michael Zinder¹, Alon Samach¹, Yuval Eshed² and Naomi Ori^1,

¹ The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture and The Otto Warburg Minerva Center for Agricultural Biotechnology, Faculty of Agriculture, Hebrew University of Jerusalem, P.O. Box 12, Rehovot 76100, Israel.
² Department of Plant Sciences, Weizmann Institute of Science, Rehovot 76100, Israel.

Author for correspondence (e-mail: ori{at}agri.huji.ac.il)

Accepted 1 January 2009

Leaves are formed at the flanks of the shoot apical meristem (SAM) and develop into a variety of forms. In tomato, prolonged leaf patterning enables the elaboration of compound leaves by reiterative initiation of leaflets with lobed margins. In goblet (gob) loss-of-function mutants, primary leaflets are often fused, secondary leaflets and marginal serrations are absent, and SAMs often terminate precociously. We show that GOB encodes a NAC-domain transcription factor expressed in narrow stripes at the leaf margins, flanking the distal side of future leaflet primordia, and at the boundaries between the SAM and leaf primordia. Leaf-specific overexpression of the microRNA miR164, a negative regulator of GOB-like genes, also leads to loss of secondary-leaflet initiation and to smooth leaflet margins. Plants carrying a dominant gob allele with an intact ORF but disrupted miR164 binding site produce more cotyledons and floral organs, have split SAMs and, surprisingly, simpler leaves. Overexpression of a form of GOB with an altered miR164 binding site in leaf primordia leads to delayed leaflet maturation, frequent, improperly timed and spaced initiation events, and a simple mature leaflet form owing to secondary-leaflet fusion. miR164 also affects leaflet separation in Cardamine hirsuta, a Brassicaceae species with complex leaves. Genetic and molecular analyses suggest that GOB expression is intact in the simplified leaves of entire tomato mutants, which have a defect in a putative repressor of auxin responses. Our results show that GOB marks leaflet boundaries and that its accurate spatial, temporal and quantitative activity affects leaf elaboration in a context-dependent manner.

Key words: CUC2, NAM, Boundary, Compound leaves, miR164, Tomato

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

Related articles in Development:

GOBLET sets boundaries in leaf development

Development 2009 136: e504. [Full Text]  

This article has been cited by other articles:

				D. Koenig, E. Bayer, J. Kang, C. Kuhlemeier, and N. Sinha Auxin patterns Solanum lycopersicum leaf morphogenesis Development, September 1, 2009; 136(17): 2997 - 3006. [Abstract] [Full Text] [PDF]