The ocean acidification effect is increasing with the large amount of CO2 emissions. To investigate the effects of future seawater acidification on Ruditapes philippinarum, a control group (pH = 8.1) and acidification group (pH = 7.7, 7.1 and 6.4) were set up for 42 days. The changes in tissue structure, immune and antioxidant enzyme activities of Ruditapes philippinarum under acidification conditions were measured, as well as the effects produced at the molecular level. The results show that when Ruditapes philippinarum are placed in an acidified seawater environment, gill filament spacing expands with decreasing pH, gill filament cilia adhere, and the pipes and outer epidermal folds of the mantle gradually deepen. The activities of acid phosphatase (ACP) and superoxide dismutase (SOD) in gill tissues show a pattern of decreasing followed by increasing. Alkaline phosphatase (AKP) activities exhibit different trends in each group. Total antioxidant capacity (T-AOC), catalase (CAT), and lysozyme (LZM) activities show a pattern of increasing followed by decreasing. Glutathione peroxidase (GSH-Px) activities in gill and visceral masses show a continuous increase. LZM activity in the viscera group displays varying trends, while ACP activity shows a decreasing and then increasing pattern. AKP, SOD, and CAT activities exhibited an increasing and then decreasing pattern, while T-AOC activity shows a continuous decrease. Analysis of the transcriptome reveals that the GO functions in gill tissue are mainly enriched in DNA integration, integral components of the membrane, and RNA-directed DNA polymerase activity, among others. The KEGG pathway analysis shows enrichment in the phagosome pathway and pathways related to protein processing in the endoplasmic reticulum. The acidification of seawater caused varying degrees of damage to the tissues of Ruditapes philippinarum, disrupting its internal environmental homeostasis and altering metabolic levels and immune-related gene expression, and led to an increased risk of disease and even death in Ruditapes philippinarum.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |