Identification and validation of reference genes for transcript normalization in strawberry (Fragaria × ananassa) defense responses

PLoS One. 2013 Aug 5;8(8):e70603. doi: 10.1371/journal.pone.0070603. Print 2013.


Strawberry (Fragaria spp) is an emerging model for the development of basic genomics and recombinant DNA studies among rosaceous crops. Functional genomic and molecular studies involve relative quantification of gene expression under experimental conditions of interest. Accuracy and reliability are dependent upon the choice of an optimal reference control transcript. There is no information available on validated endogenous reference genes for use in studies testing strawberry-pathogen interactions. Thirteen potential pre-selected strawberry reference genes were tested against different tissues, strawberry cultivars, biotic stresses, ripening and senescent conditions, and SA/JA treatments. Evaluation of reference candidate's suitability was analyzed by five different methodologies, and information was merged to identify best reference transcripts. A combination of all five methods was used for selective classification of reference genes. The resulting superior reference genes, FaRIB413, FaACTIN, FaEF1α and FaGAPDH2 are strongly recommended as control genes for relative quantification of gene expression in strawberry. This report constitutes the first systematic study to identify and validate optimal reference genes for accurate normalization of gene expression in strawberry plant defense response studies.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Fragaria / genetics*
  • Fragaria / metabolism
  • Fragaria / physiology
  • Gene Expression Regulation, Plant / genetics
  • Gene Expression Regulation, Plant / physiology
  • Plant Proteins / genetics
  • Plant Proteins / metabolism


  • Plant Proteins

Grant support

This work was supported by Junta de Andalucía (Proyecto de Excelencia P07-AGR-02482, and grants to Grupo-BIO278). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.