Expression pattern of potential heat stress genes under warm and cold episodes in scleractinian coral ‘Dipsastraea matthaii’ in the hottest sea, ‘the Persian Gulf’

Shallow water reefs are widely threatened by anthropogenic ocean warming which sometimes exceeds their thermal tolerance limit. However, certain hard coral species are thermally resilient and can quickly adapt to anomalous thermal stress events by altering the expression of their heat stress-related genes. A comparative analysis of microarray data was undertaken to identify candidate genes involved in temperature stress. Finally, to validate the results of the analysis, four genes, including [i.e., Cell Division Cycle 16 (CDC16), Ubiquitin C (UBC), Heat Shock Protein 90 Beta Family Member 1 (HSP90B1), Histone acetyltransferase p300 (EP300)] as genes responding to temperature stress in the scleractinian coral “Dipsastera matthaii” collected from the Persian Gulf were selected for real-time PCR during warm and cold periods. Expression changes of them highly confirmed the results of the meta-analysis. So that a significant increase in expression was observed for UBC, HSP90B1, and EP300 in response to heat stress. The EP300 enhancement was triggered by transcription activation through binding to transcription factors. An important feature of this response was the expression of molecular chaperones such as HSP90B1 as a result of activation of the Heat Shock Factor 1 (HSF1). In addition, HSF1 activates UBC, which removes critically digested proteins along the path of the ubiquitin proteolysis system. The outcome of this study could help introduce candidate genes that may be beneficial as biomarkers for selection.