RTN family and its response to abiotic stress in Oryza sativa

Abiotic stresses induced by climate change and soil pollution cause significant crop yield loss. Identifying stress-resistant genes for genetic improvement is urgent and necessary. Reticulon (RTN, also called RTNLB in plants) is a widely distributed endoplasmic reticulum-associated protein in eukaryotic cells, playing a crucial role in stress response activities, including autophagy, endoplasmic reticulum stress, and osmotic regulation. However, the diversity of RTNLBs in plants has hindered comprehensive analysis. This study identified 20 OsRTNLBs from Oryza sativa through a comprehensive whole-genome analysis. Detailed information on their chromosomal localization, protein motifs, phylogenetic relationships, and gene collinearity has been provided. The effects of five major abiotic stresses—cold, heat, heavy metals, salt, and drought—on rice seedling development have been assessed. The expression levels of RTNLBs under these abiotic stresses show significant changes, with an overall increase in transcription levels under simulated drought stress and a decrease under the other four stresses. Three OsRTNLBs (OsRTNLB4, OsRTNLB8 and OsRTNLB9) have been identified as key proteins contributing to abiotic stress.