Identification of the histone demethylases gene family in Glycyrrhiza inflata reveals genes responding to abiotic stresses.

Glycyrrhiza inflata Bat. is a type of abiotic-stress-resistant plant with extremely high medicinal value. Histone demethylases (HDMTs) have been known to play crucial roles in the regulation of abiotic stress response. However, the molecular functions of HDMTs has not been studied in G. inflata. Here we identified 34 GiHDMT genes in G. inflata, which could be divided into the 6 groups through phylogenetic analysis. We further found that the gene structure and conserved protein motifs exhibit high conservation in each group of GiHDMT genes. Various abiotic-stress-related elements are detected in GiHDMT promoters, especially for the light-responsive element and abscisic acid-responsive element. Collinearity analysis indicated that segmental duplication contributed to the expansion of the GiHDMT family in licorice. Subcellular localization analysis revealed that green fluorescent protein-tagged GiHDMT2 and GiHDMT18 were predominantly localized in the nucleus, whereas GiHDMT1 were found in both the cytoplasm and nucleus. Real-time quantitative polymerase chain reaction showed that GiHDMTs presented differential expression patterns across different tissues. Moreover, changes in transcription level of GiHDMTs under abiotic stress indicate the potential role of GiHDMTs in the stress response in licorice. Finally, we found the histone methylation levels probably mediated by GiHDMT genes are changed with the treatment of NaCl and Na CO . Our study will lay the foundation for future research on the regulatory roles of GiHDMT genes in the environmental stress.