AUTHOR=Zhong Chao , Liu Yu , Li Zhao , Wang Xiaoguang , Jiang Chunji , Zhao Xinhua , Kang Shuli , Liu Xibo , Zhao Shuli , Wang Jing , Zhang He , Huang Yuning , Yu Haiqiu , Xue Renfeng 

TITLE=Genome-wide analysis reveals regulatory mechanisms and expression patterns of TGA genes in peanut under abiotic stress and hormone treatments

JOURNAL=Frontiers in Plant Science

VOLUME=14

YEAR=2023

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2023.1269200

DOI=10.3389/fpls.2023.1269200

ISSN=1664-462X

ABSTRACT=<sec><title>Introduction</title><p>The <italic>TGA</italic> transcription factors, plays a crucial role in regulating gene expression. In cultivated peanut (<italic>Arachis hypogaea</italic>), which faces abiotic stress challenges, understanding the role of <italic>TGAs</italic> is important.</p></sec><sec><title>Methods</title><p>In this study, we conducted a comprehensive in analysis of the <italic>TGA</italic> gene family in peanut to elucidate their regulatory mechanisms and expression patterns under abiotic stress and hormone treatments. Furthermore, functional studies on the representative <italic>AhTGA</italic> gene in peanut cultivars were conducted using transgenic <italic>Arabidopsis</italic> and soybean hair roots.</p></sec><sec><title>Results</title><p>The genome-wide analysis revealed that a total of 20 <italic>AhTGA</italic> genes were identified and classified into five subfamilies. Collinearity analysis revealed that <italic>AhTGA</italic> genes lack tandem duplication, and their amplification in the cultivated peanut genome primarily relies on the whole-genome duplication of the diploid wild peanut to form tetraploid cultivated peanut, as well as segment duplication between the A and B subgenomes. Promoter and Protein-protein interaction analysis identified a wide range of cis-acting elements and potential interacting proteins associated with growth and development, hormones, and stress responses. Expression patterns of <italic>AhTGA</italic> genes in different tissues, under abiotic stress conditions for low temperature and drought, and in response to hormonal stimuli revealed that seven <italic>AhTGA</italic> genes from groups I (<italic>AhTGA04</italic>, <italic>AhTGA14</italic> and <italic>AhTGA20</italic>) and II (<italic>AhTGA07</italic>, <italic>AhTGA11</italic>, <italic>AhTGA16</italic> and <italic>AhTGA18</italic>) are involved in the response to abiotic stress and hormonal stimuli. The hormone treatment results indicate that these <italic>AhTGA</italic> genes primarily respond to the regulation of jasmonic acid and salicylic acid. Overexpressing <italic>AhTGA11</italic> in <italic>Arabidopsis</italic> enhances resistance to cold and drought stress by increasing antioxidant activities and altering endogenous hormone levels, particularly ABA, SA and JA.</p></sec><sec><title>Discussion</title><p>The <italic>AhTGA</italic> genes plays a crucial role in hormone regulation and stress response during peanut growth and development. The findings provide insights into peanut's abiotic stress tolerance mechanisms and pave the way for future functional studies.</p></sec>