Comparative analysis of the JRL gene family in the whole-genome of five gramineous plants

The Jacalin-related lectins (<i>JRLs</i>) gene family play a crucial role in regulating plant development and responding to environmental stress. However, a systematic bioinformatics analysis of the <i>JRL</i> gene family in Gramineae plants has been lacking. In this study, we identified 101 JRL proteins from five Gramineae species and classified them into eight distinct clades. Most of the AtJRL proteins clustered in the same group and were differentiated from the Gramineae JRL proteins. The analysis of protein motifs, gene structures and protein domain revealed that the <i>JRL</i> genes play diverse functions in Gramineae plants. Duplication events indicated that tandem duplication significantly contributed to the expansion of the JRL family, with most JRL members underwent purifying selection. Tissue expression profile analysis showed that most <i>OsJRL</i> genes were highly expressed in the roots, while <i>ZmJRL</i> genes exhibited high expression in inflorescences. Furthermore, the expression level of <i>OsJRL</i> and <i>ZmJRL</i> genes were influenced by drought, cold, heat and salt stresses, respectively, implying that these genes play important roles in response to various abiotic stresses. RT-qPCR results demonstrated that <i>OsJRL4</i> was up-regulated under PEG6000 and NaCl stresses, while <i>OsJRL12</i> and <i>OsJRL26</i> were down-regulated under PEG6000. These findings provide comprehensive insights into the <i>JRL</i> gene family in Gramineae plants and will facilitate further functional characterization of JRLs.