Identification of serine acetyltransferase (SAT) gene family in peach (Prunus persica) and study on the function of PpSAT1 gene regulating adventitious root formation

Abstract

Background

Serine acetyltransferase (SAT), an enzyme that catalyzes the formation of O-acetyl-serine (OAS), is integral to sulfur assimilation, cysteine (Cys) synthesis, and adventitious root development. However, it remains unclear how the SAT gene in Prunus persica regulates adventitious root (AR) formation.

Methods

Based on transcriptome data and SAT gene family identification, the physicochemical properties, evolutionary relationships, and cis-acting elements of the family genes were analyzed. Subsequently, the PpSAT1 gene was transformed into Prunus domestica and Arabidopsis thaliana by agrobacterium-mediated method to obtain the transgenic material, and its role in AR formation was characterized by a series of rooting index and enzyme activity experiments.

Results

In this study, based on transcriptome data, the cysteine metabolism pathway was significantly enriched during P. persica AR growth. After combining the FPKM value of transcriptome data with real-time fluorescence quantitative qRT-PCR, it was found that SAT1/4 showed high expression level, which may be a key gene in peach advection root growth. Based on this, SAT family members were identified from P. persica, and further shown by qRT-PCR, PpSAT1 gene exhibits a notable expression response during AR formation. Therefore, the PpSAT1 (Prupe.4G239400.1) gene was cloned from P. persica and performed genetic transformation on a related P. domestica as well as A. thaliana. The transgenic P. domestica and A. thaliana displayed more robust growth, and more developed root system compared to wild-type counterparts. In addition, peroxidase (POD) and superoxide dismutase (SOD) activities were also substantially elevated.

Conclusions

In summary, these findings suggest that PpSAT1 gene can facilitate AR development.

Graphical Abstract