Comparative analysis of energy metabolism differences among populations of Larimichthys crocea with different flow resistances
Large yellow croaker(Larimichthys crocea)is an important mariculture species in China,and is considered as one of the most important aquaculture species in the offshore aquaculture industry in our country.The flow resistance of fish,which plays an important role in adapting to the severe environment in deep sea,is not only related to their shape,but also significantly related to their physiological metabolism,because it can provide energy continuously for flow resistance.However,the differences of energy metabolism abilities of Larimichthys crocea in different flow resistance populations are still unclear.In order to analyze the physiological basis for the formation of flow resistance of Larimichthys crocea,samples collected in Fujian Fuding culture area(Kewan,Yuanli,Xi'ao and Hougang)were screened for flow resistance group(time against the current＞30 mins)and non-flow resistance group(time against the current＜5 mins)by self-made raceway system with a flow rate of 1.0 m·s-1.Considering the important role of the tissue(liver and muscle)energy metabolism during the process of flow resisting,differences of major energy metabolismg enzymes activity of liver and muscle between two groups,as well as their genes expression,were compared.The results showed that the activity of GDH,LDH,SDH and PK and ATP content in the muscle of flow resistance group were significantly higher than those in non-flow resistance group,indicating that the muscle of flow resistance group had stronger metabolic ability to use carbohydrate as energy source.In addition,the high ATP content in the muscle of the flow resistance group might also be one of the reasons for their strong flow resistance.On the contrary,the activity of AST,ALT and HSL in the liver of the non-flow resistance group were significantly higher than those of the flow resistance group,indicating that the liver of non-flow resistance group had a stronger metabolic capacity to use protein and lipids as energy sources.On this basis,the expressions of PK,GDH,ALT and HSL,4 energy metabolism related enzyme genes in two populations,were detected.The expression of PK and HSL in liver and muscle were basically consistent with related enzyme activities,but ALT expression was only consistent with enzyme activity in liver.Considering that ALT was mainly expressed in liver tissue rather than muscle tissue,ALT with high activity in muscle might be transported from liver,but this still needed to be further verified.Comprehensive analysis showed that carbohydrate metabolism was the main mode of energy mobilization in flow resistance group,while protein or lipids metabolism was the main mode of energy mobilization in non-flow resistance group.Due to the tight relationship between lipid and the shape of fish,further research should give more focus on this relationship or even other factors related to the flow resistance of fish,for elucidating the flow resistance mechanism of fish in severe environment of deep sea.Our study has laid an important foundation for revealing the physiological mechanism of the formation of flow resistance traits in Larimichthys crocea,and will provide data support for further breeding of flow resistance traits in Larimichthys crocea.
万方数据
维普
