Genome-Wide Characterization and Expression Analysis of Annexin Genes under High-Temperature Stress in Sorghum bicolor L.

Abstract

The annexin family is found in animals and plants and responds to a wide range of environmental stressors. In this study, 19 annexin proteins were identified based on their putative annexin repeats in Sorghum bicolor and further grouped on a phylogenic tree. These genes were randomly distributed across seven chromosomes. The amino acid length of sorghum annexins (SbAnn) varied from 241 (SbAnn3) to 370 (SbAnn2). Additionally, selective pressure analysis suggests the role of purification selection in conserving the annexin gene family in sorghum. Most SbAnns were located in the nucleus, cytoplasm, chloroplast, and mitochondrion. Also, higher syntenic relationships were observed between S. bicolor and monocots (S. italica, Z. mays, and O. sativa) than in A. thaliana. Cis-acting elements in the SbAnns gene promoters were grouped into response to light, hormone and environmental stress, and development-related elements. A number of miRNAs related to abiotic stress response targeted eleven SbAnns. Furthermore, five (SbAnn 4, 5, 14, 15, and 18) of the seven SbAnn genes utilized had relatively higher fold change under high-temperature treatment. This research provides insights into the characterization and functions of annexins under high temperatures.