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Journal of Integrative Agriculture  2026, Vol. 25 Issue (8): 3269-3281    DOI: 10.1016/j.jia.2025.11.003
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Functional analysis of tomato SlPP2C-A gene subfamily, highlighting SlPP2C7’s role in regulating saline-alkali stress tolerance

Songshen Hu1, 2, 3*, Yixuan Shang1*, Ruoxi Ding1*, Junxiao Li1, Xiaohui Hu1, 2, 3#

1 College of Horticulture, Northwest A&F University, Yangling 712100, China

2 Key Laboratory of Protected Horticultural Engineering in Northwest, Ministry of Agriculture and Rural Affairs, Yangling 712100, China

3 Shaanxi Protected Agriculture Research Centre, Yangling 712100, China

 Highlights 
14 SlPP2C-A family genes have been isolated in tomato.
The knockout SlPP2C7 can enhance the saline-alkali stress tolerance of tomato.
Integrative analysis of transcriptomics and metabolomics reveals that SlPP2C7 regulates the flavonoid biosynthetic pathway.
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摘要  

A型蛋白磷酸酶2CPP2C-A)基因家族在调控脱落酸信号通路及植物胁迫响应中具有关键作用。本研究在番茄基因组中鉴定出14SlPP2C-A基因,分布于6条染色体上。多数SlPP2C-A基因含有与生长发育、光照、激素及胁迫响应相关的顺式作用元件。共线性分析显示,番茄与拟南芥的PP2C-A基因家族具有高度同源性。组织特异性表达分析表明,SlPP2C7在花、叶及成熟果实中高表达,且受盐碱胁迫显著诱导。对盐碱胁迫处理后的SlPP2C7基因编辑敲除突变体研究证实,SlPP2C7负调控番茄的盐碱耐受性。转录组与代谢组联合分析显示,盐碱胁迫下,类黄酮生物合成、异黄酮生物合成、黄酮和黄酮醇生物合成、苯丙烷类生物合成及苯丙氨酸代谢等代谢通路显著富集。这些结果表明,SlPP2C7可能通过调控类黄酮生物合成通路增强番茄对盐碱胁迫的耐受性。本研究为解析SlPP2C7介导番茄盐碱胁迫耐受性的生理及分子机制提供了理论基础。



Abstract  The type A protein phosphatase 2C (PP2C-A) gene family is vital for regulating the ABA signaling pathway and plant stress responses.  In this research, 14 SlPP2C-A genes were identified in the tomato genome, distributed across six chromosomes.  Most SlPP2C-A genes contain cis-acting elements associated with growth, development, light, hormones, and stress responses.  Collinearity analysis revealed high homology between the tomato and Arabidopsis PP2C-A gene families.  Tissue-specific expression analysis indicated that SlPP2C7 is highly expressed in flowers, leaves, and mature fruits, and is significantly induced by saline-alkali stress.  Gene-edited SlPP2C7 knockout mutants subjected to saline-alkali stress confirmed that SlPP2C7 negatively regulates saline-alkali tolerance in tomato.  Combined transcriptomic and metabolomic analyses showed that under saline-alkali stress, metabolic pathways such as flavonoid biosynthesis, isoflavonoid biosynthesis, flavone and flavonol biosynthesis, phenylpropanoid biosynthesis, and phenylalanine metabolism were significantly enriched.  These outcomes imply that SlPP2C7 may enhance tolerance to saline-alkali stress through modulating flavonoid biosynthesis pathways.  This research reveals comprehension of the physiological and molecular mechanism responsible for saline-alkali stress tolerance mediated by SlPP2C7 in tomato.
Keywords:  tomato       SlPP2C-A gene family       SlPP2C7       saline-alkali stress       transcriptome       metabolome       flavonoids  
Received: 31 March 2025   Accepted: 17 June 2025 Online: 07 November 2025  
Fund: 

This work was supported by the National Natural Science Foundation of China (32302531) and the Scientific Startup Foundation for Doctors of Northwest A&F University, China (Z1090123026).

About author:  #Correspondence Xiaohui Hu, E-mail: hxh1977@163.com * These authors contributed equally to this study.

Cite this article: 

Songshen Hu, Yixuan Shang, Ruoxi Ding, Junxiao Li, Xiaohui Hu. 2026. Functional analysis of tomato SlPP2C-A gene subfamily, highlighting SlPP2C7’s role in regulating saline-alkali stress tolerance. Journal of Integrative Agriculture, 25(8): 3269-3281.

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