Xingguo Zhang, Yingying Ma, Ding Qiu, Kuopeng Wang, Yang Yang, Yinghui Liu, Zhongfeng Li, Fangping Gong, Kai Zhao, Lin Zhang, Xingli Ma* and Dongmei Yin
Cultivated peanut, as a major oil and cash crop, plays a critical role in ensuring global oil production security. The Sieve Element Occlusion (SEO) gene, which encodes phloem structural proteins widely distributed across plants, is essential for plant growth, development, and stress responses. However, a comprehensive analysis of SEOs in peanuts has not been conducted to date. In this study, a total of 36 AhSEOs were systematically identified and mapped to 10 chromosomes. Analysis of deduced protein properties, gene structure, conserved motifs, and cis-acting regulatory elements revealed the diverse characteristics of AhSEOs. The expression profiles of the 36 genes in 22 tissues revealed that they might have different roles. Among them, two genes, AhSEO15 and AhSEO33, were specifically expressed in root and nodule. Resequencing data from two lines with differing drought resistance, wild-type H2014 and its mutant H1314, revealed a Single Nucleotide Polymorphism (SNP) in AhSEO15 that leads to premature translation termination and alters its threedimensional structure in H1314. Transformation of Arabidopsis thaliana with AhSEO15 demonstrated that, under osmotic stress, plants overexpressing AhSEO15 exhibited higher seed germination rates and improved root growth compared to wild-type plants, suggesting that this gene may play a role in drought resistance. Moreover, lines overexpressing AhSEO15_H2014 showed enhanced drought resistance, whereas lines overexpressing AhSEO15_H1314 displayed reduced drought tolerance, highlighting the potential link between gene structure and drought stress resistance.
