Genome-wide analysis of the superoxide dismutase (SOD) gene family in Zostera marina and expression profile analysis under temperature stress

Yu Zang; Jun Chen; Ruoxi Li; Shuai Shang; Xuexi Tang

doi:10.7717/peerj.9063

Genome-wide analysis of the superoxide dismutase (SOD) gene family in Zostera marina and expression profile analysis under temperature stress

PeerJ. 2020 May 5:8:e9063. doi: 10.7717/peerj.9063. eCollection 2020.

Authors

Yu Zang^#^{1

2}, Jun Chen^#^{1

2}, Ruoxi Li³, Shuai Shang⁴, Xuexi Tang^{1

2}

Affiliations

¹ College of Marine Life Sciences, Ocean University of China, Qingdao, China.
² Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China.
³ School of Life Science, Southwest University, Chongqing, China.
⁴ College of Biological and Environmental Engineering, Binzhou University, Binzhou, China.

^# Contributed equally.

Abstract

Superoxide dismutases (SODs) serve as the first line of defense in the plant antioxidant enzyme system, and play a primary role in the removal of reactive oxygen species (ROS). However, our understanding of the functions of the SOD family in Zostera marina is limited. In this study, a systematic analysis was conducted on the characteristics of the SOD genes in Z. marina at the whole-genome level. Five SOD genes were identified, consisting of two Cu/ZnSODs, two FeSODs, and one MnSOD. Phylogenetic analysis showed that ZmSOD proteins could be divided into two major categories (Cu/ZnSODs and Fe-MnSODs). Sequence motifs, gene structure, and the 3D-modeled protein structures further supported the phylogenetic analysis, with each subgroup having similar motifs, exon-intron structures, and protein structures. Additionally, several cis-elements were identified that may respond to biotic and abiotic stresses. Transcriptome analysis revealed expression diversity of ZmSODs in various tissues. Moreover, qRT-PCR analysis showed that the expression level of most ZmSOD genes trended to decreased expression with the increase of temperature, indicating that heat stress inhibits expression of ZmSODs and may result in reduced ability of ZmSODs to scavenge ROS. Our results provide a basis for further functional research on the SOD gene family in Z. marina, which will help to determine the molecular mechanism of ZmSOD genes in response to environmental stress.

Keywords: Gene families; Global change; Superoxide dismutases; Temperature stress; Zostera marina.

Grants and funding

This work was supported by the NSFC-Shandong Joint Fund (U1806213) and NSFC-Shandong Joint Fund for Marine Ecology and Environmental Sciences (No. U1606404). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.