Identification of Aldehyde Dehydrogenase Gene Family in Glycyrrhiza uralensis and Analysis of Expression Pattern Under Drought Stress

<i>Aldehyde dehydrogenases</i> (<i>ALDHs</i>) are a gene family that relies on NAD +/NADP + proteins to oxidize toxic aldehydes to non-toxic carboxylic acids, and they play a crucial role in the growth and development of plants, as well as in their ability to withstand stress. This study identified 26 <i>ALDH</i> genes from six <i>Glycyrrhiza uralensis</i> gene families distributed on six chromosomes. By analyzing the phylogeny, gene structure, conserved motifs, cis-regulatory elements, collinearity of homologs, evolutionary patterns, differentiation patterns, and expression variations under drought stress, we found that the <i>ALDH</i> gene is involved in phytohormones and exhibits responsiveness to various environmental stressors by modulating multiple cis-regulatory elements. In addition, <i>GuALDH3H1</i>, <i>GuALDH6B1</i>, <i>GuALDH12A2</i>, and <i>GuALDH12A1</i> have been identified as playing a crucial role in the response to drought stress. By analyzing the expression patterns of different tissues under drought stress, we discovered that <i>GuALDH3I2</i> and <i>GuALDH2B2</i> exhibited the most pronounced impact in relation to the drought stress response, which indicates that they play a positive role in the response to abiotic stress. These findings provide a comprehensive theoretical basis for the <i>ALDH</i> gene family in <i>Glycyrrhiza uralensis</i> and enhance our understanding of the molecular mechanisms underlying <i>ALDH</i> genes in licorice growth, development, and adaptation to drought stress.