Genome-Wide Identification of NAC Family Genes in Oat and Functional Characterization of AsNAC109 in Abiotic Stress Tolerance

Abstract

The plant-specific <i>NAC</i> gene family is one of the largest transcription factor families, participating in plant growth regulation and stress response. Despite extensive characterization in various plants, our knowledge of the <i>NAC</i> family in oat is lacking. Herein, we identified 333 <i>NAC</i> genes from the latest release of the common oat genome. We provide a comprehensive overview of the oat <i>NAC</i> gene family, covering gene structure, chromosomal localization, phylogenetic characteristics, conserved motif compositions, and gene duplications. <i>AsNAC</i> gene expression in different tissues and the response to various abiotic stresses were characterized using RT-qPCR. The main driver of oat <i>NAC</i> gene family expansion was identified as segmental duplication using collinearity analysis. In addition, the functions of <i>AsNAC109</i> in regulating abiotic stress tolerance in <i>Arabidopsis</i> were clarified. This is the first genome-wide investigation of the <i>NAC</i> gene family in cultivated oat, which provided a unique resource for subsequent research to elucidate the mechanisms responsible for oat stress tolerance and provides valuable clues for the improvement of stress resistance in cultivated oat.