Thermal stress induced metabolic changes in male gamete of Ecklonia cava

Abstract

The impact of ocean warming on a kelp was evaluated in male gamete of Ecklonia cava by RNA-seq. The series of differentially expressed gene (DEG) profiling were carried out in the groups of male gametes which exposed to 15 °C for 0.5, 1, 3, 5 day (d) in each. A group of male gametes cultured at 15 °C was used as a control. The biological process ontology (level 3) for the genes which expression was affected by the thermal exposure were analyzed using the default parameters of DAVID version 6.7 (Database for Annotation, Visualization, and Integrated Discovery; https://david.ncifcrf.gov/). In the 0.5 d exposed group, the terms related to negative regulation of biological process, regulation of macromolecule metabolic process, cellular nitrogen compound metabolic process, nucleobase-containing compound metabolic process, protein metabolic process, heterocycle metabolic process, organic cyclic compound metabolic process, and organic substance biosynthetic process were deduced from the DEGs. For the 1.0 d exposed male gametes, cellular nitrogen compound metabolic process, heterocycle metabolic process, organic cyclic compound metabolic process, and nucleobase-containing compound metabolic process were inferred. Organonitrogen compound metabolic process, cellular biosynthetic process, cellular nitrogen compound metabolic process, and cellular macromolecule metabolic process were analyzed in the 3.0 d exposed group. Cellular nitrogen compound metabolic process, and cellular macromolecule metabolic process, seemed to be altered in the 5.0 d exposed experimental group. The results will contribute to extend our knowledge in the physiological and/or metabolic changes in the thermal stressed male gametes of kelp species.