AUTHOR=Luo Lu , Wan Qian , Zhang Kun , Zhang Xiurong , Guo Ruijie , Wang Cai , Zheng Chengchao , Liu Fengzhen , Ding Zhaojun , Wan Yongshan 

TITLE=AhABI4s Negatively Regulate Salt-Stress Response in Peanut

JOURNAL=Frontiers in Plant Science

VOLUME=12

YEAR=2021

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2021.741641

DOI=10.3389/fpls.2021.741641

ISSN=1664-462X

ABSTRACT=<p>Soil salinity is one of the major factors that limit the area of cultivable land and yield potential of crops. The ability of salt tolerance varies with plant species. Peanut (<italic>Arachis hypogaea</italic> L.) is a moderately salt-sensitive and economically important crop, however, their biological processes involved in salt-stress response remain unclear. In this study, we investigated the role of <italic>A. hypogaea</italic> L. ABSCISIC ACID INSENSITIVE 4s (<italic>AhABI4s</italic>) in salt tolerance and elucidated its mode of action in peanuts. The results showed that the downregulation of <italic>AhABI4</italic>s <italic>via</italic> whole plant virus-induced gene silencing has enhanced the survival rate, biomass accumulation, and root/shoot ratio of peanut seedlings in response to salt-stress. Transcriptomics, quantitative proteomics, and phosphoproteomic analyses were performed using <italic>AhABI4</italic>s-silenced and Mock plants. The expression pattern of 15,247 genes, 1,900 proteins, and 2,620 phosphorylation sites were affected by silencing of <italic>AhABI4</italic>s in peanut leaf and root after sodium chloride (NaCl) treatment. Among them, 63 potential downstream target genes of ABI4 changed consistently at both transcription and translation levels, and the protein/phosphorylation levels of 31 ion transporters/channels were also affected. Electrophoretic mobility shift assays (EMSA) showed that ABI4 was able to bind to the promoters of <italic>HSP70, fructokinase</italic> (<italic>FRK</italic>), and <italic>pyruvate kinase</italic> (<italic>PK</italic>) coding genes <italic>in vitro</italic>. In addition, we also detected a binding preference of <italic>AhABI4</italic> for CACT(G/T)GCA motif in the promoters of down-regulated genes in peanut leaf. Collectively, the potential downstream targets which were regulated at the levels of transcription and translation, binding preference, and <italic>in vivo</italic> phosphorylation sites that had been revealed in this study will provide new insight into the <italic>AhABI4s</italic>-mediated salt tolerance regulation mechanism in peanuts.</p>