Abstract:

Objective To investigate the function of the oat (Avena sativa L.) AsGolS2 in response to saline-alkali stress, thereby providing a basis for elucidating the molecular regulatory mechanisms it mediates. Method The AsGolS2 gene was cloned from six oat varieties and subjected to sequence polymorphism analysis. The representative variety ‘Dingyou 2’ was selected for full-length cDNA cloning of AsGolS2, followed by bioinformatics analysis. Real-time quantitative PCR (RT-qPCR) was employed to examine the expression variations in the leaves under varying concentrations of saline-alkali stress. Additionally, the leaves of ‘Dingyou 2’ subjected to saline-alkali stress were used to construct a normalized yeast two-hybrid (Y2H) cDNA library, which was subsequently utilized to screen for interacting proteins of AsGolS2. Result Sequence alignment of multiple oat varieties indicates that genetic variation in the AsGolS2 gene primarily resides within the untranslated regions (UTRs). The coding sequence (CDS) of AsGolS2 is 984 bp in length, comprising three exons and encoding 327 amino acids. The resulting protein possesses a conserved domain characteristic of the GT8 family and lacks transmembrane structures. Predicted results of secondary structure indicate that the encoded protein comprises 33.03% α-helices, 10.70% extended chains, and 56.27% disordered coils. Phylogenetic analysis reveals that oat AsGolS2 shares the closest relationship with the wheat TaGolS2 protein. RT-qPCR analysis demonstrates that the expression of the AsGolS2 in leaves is significantly induced by saline-alkali stress, exhibiting an initial increase followed by a subsequent decrease across different stress concentrations. Y2H screening identified 45 candidate interacting proteins for AsGolS2, among which proteins involved in metabolic processes constitute the largest proportion. Conclusion The AsGolS2 gene of oat is successfully cloned, with its expression in leaves induced by saline-alkali stress. The 45 candidate proteins interacting with AsGolS2 are identified. Their functions span multiple biological processes, including metabolism, signal transduction, and protein homeostasis.

Key words: Avena sativa L., AsGolS2, saline-alkali stress, bioinformatics, interacting protein