Increased leaf size: different means to an end

Plant Physiol. 2010 Jul;153(3):1261-79. doi: 10.1104/pp.110.156018. Epub 2010 May 11.


The final size of plant organs, such as leaves, is tightly controlled by environmental and genetic factors that must spatially and temporally coordinate cell expansion and cell cycle activity. However, this regulation of organ growth is still poorly understood. The aim of this study is to gain more insight into the genetic control of leaf size in Arabidopsis (Arabidopsis thaliana) by performing a comparative analysis of transgenic lines that produce enlarged leaves under standardized environmental conditions. To this end, we selected five genes belonging to different functional classes that all positively affect leaf size when overexpressed: AVP1, GRF5, JAW, BRI1, and GA20OX1. We show that the increase in leaf area in these lines depended on leaf position and growth conditions and that all five lines affected leaf size differently; however, in all cases, an increase in cell number was, entirely or predominantly, responsible for the leaf size enlargement. By analyzing hormone levels, transcriptome, and metabolome, we provide deeper insight into the molecular basis of the growth phenotype for the individual lines. A comparative analysis between these data sets indicates that enhanced organ growth is governed by different, seemingly independent pathways. The analysis of transgenic lines simultaneously overexpressing two growth-enhancing genes further supports the concept that multiple pathways independently converge on organ size control in Arabidopsis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Abscisic Acid / metabolism
  • Arabidopsis / anatomy & histology*
  • Arabidopsis / cytology
  • Arabidopsis / genetics
  • Arabidopsis / growth & development
  • Arabidopsis Proteins / genetics
  • Arabidopsis Proteins / metabolism
  • Brassinosteroids
  • Cell Count
  • Cholestanols / metabolism
  • Cyclopentanes / metabolism
  • Gene Expression Profiling
  • Gene Expression Regulation, Plant
  • Genes, Plant / genetics
  • Inorganic Pyrophosphatase / genetics
  • Inorganic Pyrophosphatase / metabolism
  • Inositol / metabolism
  • Metabolome
  • Organ Size
  • Oxylipins / metabolism
  • Phenotype
  • Plant Leaves / anatomy & histology*
  • Plant Leaves / cytology
  • Plant Leaves / genetics
  • Plant Leaves / growth & development
  • Protein Kinases / genetics
  • Protein Kinases / metabolism
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Signal Transduction
  • Steroids, Heterocyclic / metabolism


  • Arabidopsis Proteins
  • Brassinosteroids
  • Cholestanols
  • Cyclopentanes
  • Oxylipins
  • RNA, Messenger
  • Steroids, Heterocyclic
  • Inositol
  • jasmonic acid
  • Abscisic Acid
  • Protein Kinases
  • BRI1 protein, Arabidopsis
  • AVP1 protein, Arabidopsis
  • Inorganic Pyrophosphatase
  • brassinolide

Associated data

  • OMIM/GSE20458