Transcriptome profiling of the gills to air exposure in mud crab Scylla paramamosain

The mud crab Scylla paramamosain is a valuable commercial mariculture crab worldwide. During the ebb tide or when transported to market, crabs suffer underlying air exposure stress. Gills tissue is the first tissue to cope with this stress. In this study, the transcriptome of S. paramamosain gills from the control group (CG) and experimental group (EG) were sequenced, assembled, and compared. A total of 7,425,620,293 bp and 6,741,616,977 bp clean data were found in EG and CG, respectively. A total of 38,507 unigenes (42.78%) were annotated successfully. 13,626 differentially expressed genes (DEGs) were up-regulated, and 6,502 DEGs were down-regulated. The DEGs related to immunity, apoptosis, metabolism, and ion exchange were detected. DEGs were enriched significantly into the KEGG pathways related to metabolism and immunity. These results proved that more material and energy were required, and immune defense was enhanced when the crab was under air exposure stress. The present study provides the first-gill transcriptomic analysis challenged with air exposure stress in S. paramamosain under air exposure stress, which will be useful to clarify the molecular mechanisms of air exposure adaptation.