AUTHOR=Wang Wei , Cheng Mingxing , Wei Xiao , Wang Ruihua , Fan Fengfeng , Wang Zhikai , Tian Zhihong , Li Shaoqing , Yuan Huanran 

TITLE=Comprehensive evolutionary analysis of growth-regulating factor gene family revealing the potential molecular basis under multiple hormonal stress in Gramineae crops

JOURNAL=Frontiers in Plant Science

VOLUME=14

YEAR=2023

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2023.1174955

DOI=10.3389/fpls.2023.1174955

ISSN=1664-462X

ABSTRACT=<p><italic>Growth-regulating factors</italic> (<italic>GRFs</italic>) are plant-specific transcription factors that contain two highly conserved QLQ and WRC domains, which control a range of biological functions, including leaf growth, floral organ development, and phytohormone signaling. However, knowledge of the evolutionary patterns and driving forces of <italic>GRFs</italic> in <italic>Gramineae</italic> crops is limited and poorly characterized. In this study, a total of 96 <italic>GRFs</italic> were identified from eight crops of <italic>Brachypodium distachyon</italic>, <italic>Hordeum vulgare</italic>, <italic>Oryza sativa</italic> L. ssp. <italic>indica</italic>, <italic>Oryza rufipogon</italic>, <italic>Oryza sativa</italic> L. ssp. <italic>japonica</italic>, <italic>Setaria italic</italic>, <italic>Sorghum bicolor</italic> and <italic>Zea mays</italic>. Based on their protein sequences, the <italic>GRFs</italic> were classified into three groups. Evolutionary analysis indicated that the whole-genome or segmental duplication plays an essential role in the <italic>GRFs</italic> expansion, and the <italic>GRF</italic>s were negatively selected during the evolution of <italic>Gramineae</italic> crops. The GRFs protein function as transcriptional activators with distinctive structural motifs in different groups. In addition, the expression of <italic>GRFs</italic> was induced under multiple hormonal stress, including IAA, BR, GA3, 6BA, ABA, and MeJ treatments. Specifically, <italic>OjGRF11</italic> was significantly induced by IAA at 6 h after phytohormone treatment. Transgenic experiments showed that roots overexpressing <italic>OjGRF11</italic> were more sensitive to IAA and affect root elongation. This study will broaden our insights into the origin and evolution of the GRF family in <italic>Gramineae</italic> crops and will facilitate further research on <italic>GRF</italic> function.</p>