Transcriptome profiling of cytokinin and auxin regulation in tomato root

J Exp Bot. 2013 Jan;64(2):695-704. doi: 10.1093/jxb/ers365.

Abstract

Tomato is a model and economically important crop plant with little information available about gene expression in roots. Currently, there have only been a few studies that examine hormonal responses in tomato roots and none at a genome-wide level. This study examined the transcriptome atlas of tomato root regions (root tip, lateral roots, and whole roots) and the transcriptional regulation of each root region in response to the plant hormones cytokinin and auxin using Illumina RNA sequencing. More than 165 million 1×54 base pair reads were mapped onto the Solanum lycopersicum reference genome and differential expression patterns in each root region in response to each hormone were assessed. Many novel cytokinin- and auxin-induced and -repressed genes were identified as significantly differentially expressed and the expression levels of several were confirmed by qPCR. A number of these regulated genes represent tomato orthologues of cytokinin- or auxin-regulated genes identified in other species, including CKXs, type-A RRs, Aux/IAAs, and ARFs. Additionally, the data confirm some of the hormone regulation studies for recently examined genes in tomato such as SlIAAs and SlGH3s. Moreover, genes expressed abundantly in each root region were identified which provide a spatial distribution of many classes of genes, including plant defence, secondary metabolite production, and general metabolism across the root. Overall this study presents the first global expression patterns of hormone-regulated transcripts in tomato roots, which will be functionally relevant for future studies directed towards tomato root growth and development.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Cytokinins / metabolism*
  • Gene Expression Profiling*
  • Gene Expression Regulation, Plant
  • Indoleacetic Acids / metabolism*
  • Lycopersicon esculentum / genetics*
  • Lycopersicon esculentum / growth & development
  • Lycopersicon esculentum / metabolism
  • Plant Growth Regulators / metabolism*
  • Plant Proteins / genetics
  • Plant Proteins / metabolism
  • Plant Roots / genetics*
  • Plant Roots / growth & development
  • Plant Roots / metabolism

Substances

  • Cytokinins
  • Indoleacetic Acids
  • Plant Growth Regulators
  • Plant Proteins