Selection of reference genes for quantitative gene expression analyses in pedunculate oak (Quercus robur L.) using real-time quantitative PCR

Abstract

Drought and desertification are global issues leading to numerous negative consequences, such as reducing the arable land area, decreasing soil fertility, and crop yield. An effective method to fight against degradation and desertification of agricultural lands is agroforestry, thus there is a need to obtain drought-resistant tree species for use in agroforestry on arid lands. One of the key species used for creating forest strips is pedunculate oak (Quercus robur L.). Understanding the molecular mechanisms of adaptation to drought conditions is necessary to obtain resistant tree species. Real-time quantitative PCR method allows studying gene expression changes under various stress factors, but accurate results require careful selection of reference genes. The aim of this study is to select reference genes for quantitative gene expression analysis of Q. robur using RT-qPCR. Modeling of soil drought in the laboratory conditions was conducted to evaluate the stability of housekeeping genes expression in Q. robur. The RT-qPCR data were analyzed using the RefFinder web tool. Results from various algorithms showed that ACT7 had the most stable expression, while EF1α had the least stable expression. ACT7 is recommended as the reference gene for gene expression studies of Q. robur under drought conditions.