The Nascent Polypeptide-Associated Complex Subunit Alpha-Like Protein 1 (PmNACA1) Enhances Drought Tolerance by Scavenging ROS in Prunus mira Koehne

Abstract

Extreme environmental stress significantly impacts plant growth. Drought stress is one of the most important abiotic stresses, adversely affecting plant development and agricultural productivity. Prunus mira is an exceptionally drought-tolerant plant. However, there are a limited number studies on the drought resistance of it. Here, we isolated and identified nascent polypeptide-associated complex subunit alpha-like protein 1 of P. mira (PmNACA1). PmNACA1 comprises 201 amino acids and contains an NAC domain at its N-terminal. It was localized in the cytoplasm and nucleus. PmNACA1 was primarily expressed in leaves, and was induced by drought. PmNACA1 overexpression Arabidopsis thaliana increased germination and root elongation. Histochemical staining revealed that the overexpression lines accumulated less ROS under mannitol-induced osmotic stress. Under drought stress, overexpression lines exhibited an elevation in the activities of SOD, POD, CAT, and GR and a rise in the levels of GSH and GSSG. In addition, the overexpression lines exhibited relatively lower levels of H₂O₂, O₂^.−, MDA, and electrical conductivity than control plants. PmNACA1 induced the expression of drought- and ABA-related genes after drought treatment. PmNACA1 scavenged H₂O₂, DPPH radicals, and hydroxyl radicals in vitro. In summary, we conclude that PmNACA1 plays an active role in drought stress response by scavenging ROS.