Physiological responses and transcriptomic analysis of StCPD gene overexpression in potato under salt stresses

Front Plant Sci. 2024 Feb 16:15:1297812. doi: 10.3389/fpls.2024.1297812. eCollection 2024.

Abstract

Introduction: The potato (Solanum tuberosum L.), one of the most vital food crops worldwide, is sensitive to salinity. Brassinosteroids (BRs) are crucial in tolerance to various abiotic stresses. The constitutive photomorphogenesis and dwarf (CPD) gene encodes C-3 oxidase, which is a rate-limiting enzyme that controls the synthesis of BRs.

Methods: In this study, we used StCPD gene overexpression (T) and un-transgenic (NT) plants obtained from our former research to illustrate adaptive resistance to salt stress at levels of phenotype; cell ultrastructure, physiology, and biochemistry; hormone; and transcription.

Results: Results showed the accumulation of 2,4-epibrassionolide (EBL) in T potatoes. We found that under high salt situations, the changed Na+/K+ transporter gene expression was linked with the prevalent ionic responses in T plants, which led to lower concentrations of K+ and higher concentrations of Na+ in leaves. Furthermore, RNA-sequencing (RNA-seq) data elucidated that gene expressions in NT and T plants were significantly changed with 200-mM NaCl treatment for 24 h and 48 h, compared with the 0-h treatment. Functional enrichment analysis suggested that most of the differentially expressed genes (DEGs) were related to the regulation of BR-related gene expression, pigment metabolism process, light and action, and plant hormone signal transduction.

Discussion: These findings suggested that StCPD gene overexpression can alleviate the damage caused by salt stress and enhance the salt resistance of potato plantlets. Our study provides an essential reference for further research on BR regulation of plant molecular mechanisms in potatoes with stress tolerance.

Keywords: StCPD gene; brassinosteroids metabolism; potato; salt stress; transcriptome.

Grants and funding

The author(s) declare financial support was received for the research, authorship, and/or publication of this article. This study was supported by the National Natural Science Foundation of China (grant numbers 31960443)/Research Program Sponsored by the State Key Laboratory of Aridland Crop Science. Gansu Agricultural University (grant numbers GSCS-2018-4)/Research Program Sponsored by the Youth Mentor Fund. Gansu Agricultural University (grant numbers GSAU-QDFC-2021-14).