Identification and expression analysis of AQPs family genes in Glycyrrhiza uralensis

Aquaporins (AQPs), which are located in the plasma membrane, play an important role in regulating plant water balance. Glycyrrhiza uralensis is a commonly used medicinal plant under high demand. This species grows in arid environments, and water balance markedly affects its growth. To improve the understanding of AQP functions in G. uralensis, members of the GuAQPs family genes were analyzed through bioinformatics. Transcriptome data and qRT-PCR were combined to analyze the expression ofGuAQPs under abiotic stress. The results confirmed 43 GuAQPs genes in G. uralensis, which were mainly divided into four subfamilies: PIPs, TIPs, NIPs, and SIPs. They all contained a MIP domain, a NAP motif, Ar/R selective filters, and Froger’s positions, and their secondary structure was mainly random curls. The promoter region of GuAQPs genes comprised cis-acting elements and respond to hormone signaling and stress. Expression of GuTIP2;3 was significantly up-regulated in leaves and roots after drought or ABA treatment. Expression of GuSIP1;4 and GuNIP6;1 was significantly up-regulated in leaves and roots after salt stress (P < 0.05), whereas GuTIP4;1 expression was down-regulated in roots after salt stress (P < 0.05). Expression of GuNIP6;1 and GuSIP1;2 was significantly down-regulated in roots and leaves under low temperatures (P < 0.05). Based on genome-wide identification and expression analysis of AQPs, these results provide a theoretical basis for further research on the molecular mechanism of G. uralensis growth and development under stress.