StUBC13, a Ubiquitin-Conjugating Enzyme, Positively Regulates Salt and Osmotic Stresses in Potato.

Protein ubiquitination is an important regulatory mechanism for biological growth and development against environmental influences, and can affect several biological processes, including the growth, development, and stress responses of plants. However, the function of potato-related ubiquitin-conjugating enzymes in abiotic stress tolerance is poorly understood. In this study, a with a UBC conserved structural domain was identified in potato and its function was investigated under osmotic stress and salt stress conditions. The observation of plant phenotypes under stress conditions revealed that overexpressed plants grew better than wild-type plants. In line with the above results, the determination of stress-related physiological indices revealed that the overexpression transgenic plants had better stress tolerance and stronger adaptation to environmental stress, and the transgenic plants were found to tolerate better drought and salt stress by decreasing their malondialdehyde (MDA) content and increasing their superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) contents under stress conditions. Based on these results, StUBC13 has an important regulatory role in the response of plants to abiotic stresses (osmotic stress and salt stress), and overexpression of this gene can improve the tolerance of potatoes to osmotic and salt stresses.