Validation of potential reference genes for qPCR in maize across abiotic stresses, hormone treatments, and tissue types

PLoS One. 2014 May 8;9(5):e95445. doi: 10.1371/journal.pone.0095445. eCollection 2014.

Abstract

The reverse transcription quantitative polymerase chain reaction (RT-qPCR) is a powerful and widely used technique for the measurement of gene expression. Reference genes, which serve as endogenous controls ensure that the results are accurate and reproducible, are vital for data normalization. To bolster the literature on reference gene selection in maize, ten candidate reference genes, including eight traditionally used internal control genes and two potential candidate genes from our microarray datasets, were evaluated for expression level in maize across abiotic stresses (cold, heat, salinity, and PEG), phytohormone treatments (abscisic acid, salicylic acid, jasmonic acid, ethylene, and gibberellins), and different tissue types. Three analytical software packages, geNorm, NormFinder, and Bestkeeper, were used to assess the stability of reference gene expression. The results revealed that elongation factor 1 alpha (EF1α), tubulin beta (β-TUB), cyclophilin (CYP), and eukaryotic initiation factor 4A (EIF4A) were the most reliable reference genes for overall gene expression normalization in maize, while GRP (Glycine-rich RNA-binding protein), GLU1(beta-glucosidase), and UBQ9 (ubiquitin 9) were the least stable and most unsuitable genes. In addition, the suitability of EF1α, β-TUB, and their combination as reference genes was confirmed by validating the expression of WRKY50 in various samples. The current study indicates the appropriate reference genes for the urgent requirement of gene expression normalization in maize across certain abiotic stresses, hormones, and tissue types.

Publication types

  • Research Support, Non-U.S. Gov't
  • Validation Study

MeSH terms

  • Abscisic Acid / pharmacology
  • Cyclopentanes / pharmacology
  • Cyclophilins / genetics*
  • Droughts
  • Ethylenes / pharmacology
  • Eukaryotic Initiation Factor-4A / genetics*
  • Gene Expression Regulation, Plant / drug effects*
  • Genes, Essential / drug effects
  • Genes, Plant*
  • Gibberellins / pharmacology
  • Oxylipins / pharmacology
  • Peptide Elongation Factor 1 / genetics*
  • Real-Time Polymerase Chain Reaction / methods*
  • Salicylic Acid / pharmacology
  • Zea mays / genetics*

Substances

  • Cyclopentanes
  • Ethylenes
  • Gibberellins
  • Oxylipins
  • Peptide Elongation Factor 1
  • jasmonic acid
  • Abscisic Acid
  • ethylene
  • Eukaryotic Initiation Factor-4A
  • Cyclophilins
  • Salicylic Acid

Grants and funding

This work is supported by grants from National Natural Science Foundation of China (No. 30800687 and No. 31071434)(http://www.nsfc.gov.cn/Portal0/default152.htm), Ph.D. Programs Foundation of Ministry of Education of China (1.20125103110011)(http://www.moe.gov.cn/publicfiles/business/htmlfiles/moe/moe_249/index.html), Scientific Research Foundation for the Returned Overseas Chinese Scholars, State Education Ministry(http://fund.cscse.edu.cn/Login.aspx). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.