Cloning and Expression Analysis of 9-cis-Epoxycarotenoid Dioxygenase Gene 1 Involved in Fruit Maturation and Abiotic Stress Response in Lycium chinense

Abstract

Abscisic acid (ABA) plays a crucial role in plant adaptations to environmental stress, growth, and development, such as seed dormancy and germination. 9-cis-epoxycarotenoid dioxygenase (NCED) is a rate-limiting enzyme in regulation of ABA biosynthesis in plants. To understand the potential role of NCED in fruit ripening and stress tolerance, a NCED gene (LcNCED1) was cloned from the leaves of Lycium chinense. LcNCED1 has an ORF of 1824 bp, which encodes a peptide of 607 amino acids. The deduced amino acid sequence of the LcNCED1 protein shares high identity with other NCEDs. Tissue distribution analysis reveals that LcNCED1 is abundantly expressed in leaves, stems, and flowers. In fruits, the expression level of LcNCED1 is in accordance with the accumulation of ABA. In addition, ABA accumulation in leaves was associated with enhanced expression of LcNCED1 induced strongly by abiotic stresses (drought, salt, and CdCl2). Collectively, our results indicated that LcNCED1 might play a key role in the regulation of fruit ripeness and abiotic stress adaption in L. chinense possibly through regulation of ABA biosynthesis.