AUTHOR=Shao An , Fan Shugao , Xu Xiao , Wang Wei , Fu Jinmin 

TITLE=Identification and evolution analysis of YUCCA genes of Medicago sativa and Medicago truncatula and their expression profiles under abiotic stress

JOURNAL=Frontiers in Plant Science

VOLUME=14

YEAR=2023

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2023.1268027

DOI=10.3389/fpls.2023.1268027

ISSN=1664-462X

ABSTRACT=<p>The YUCCAs (YUC) are functionally identified flavin-containing monooxidases (FMOs) in plants that act as an important rate-limiting enzyme functioning in the auxin synthesis IPA (indole-3-pyruvic acid) pathway. In this study, 12 MsYUCs and 15 MtYUCs containing characteristic conserved motifs were identified in <italic>M. sativa</italic> (<italic>Medicago sativa</italic> L.) and <italic>M. truncatula</italic> (<italic>Medicago truncatula</italic> Gaertn.), respectively. Phylogenetic analysis revealed that YUC proteins underwent an evolutionary divergence. Both tandem and segmental duplication events were presented in <italic>MsYUC</italic> and <italic>MtYUC</italic> genes. Comparative syntenic maps of <italic>M. sativa</italic> with <italic>M. truncatula</italic>, <italic>Arabidopsis</italic> (<italic>Arabidopsis thaliana</italic>), or rice (<italic>Oryza sativa</italic> L.) were constructed to illustrate the evolution relationship of the YUC gene family. A large number of cis-acting elements related to stress response and hormone regulation were revealed in the promoter sequences of <italic>MsYUCs</italic>. Expression analysis showed that <italic>MsYUCs</italic> had a tissue-specific, genotype-differential expression and a differential abiotic stress response pattern based on transcriptome data analysis of <italic>M. sativa</italic> online. In addition, RT-qPCR confirmed that salt stress significantly induced the expression of <italic>MsYUC1/MsYUC10</italic> but significantly inhibited <italic>MsYUC2/MsYUC3</italic> expression and the expression of <italic>MsYUC10/MsYUC11/MsYUC12</italic> was significantly induced by cold treatment. These results could provide valuable information for functional analysis of <italic>YUC</italic> genes via gene engineering of the auxin synthetic IPA pathway in <italic>Medicago</italic>.</p>