Morphological characteristics of Squaliobarbus curriculus and tissue specificity analysis for two isozymes

ObjectiveThe purpose of the present work was to enrich the research data about germplasm resources of Squaliobarbus curriculus from morphological characteristics and biochemical genetic levels,and to lay the foundation for screening out of the biochemical genetic marker for identifying the population of S.curriculus.MethodThe morphologi-cal characteristics of S.curriculus were observed by morphological measurement.Lactate dehydrogenase(LDH)and ma-late dehydrogenase(MDH)isozymes from five tissues(heart,eye,muscle,liver and kidney)were detected by polyacryla-mide gel electrophoresis,and the tissue specificities expressed by two kinds of isozymes were analyzed.ResultThere was a red spot on upper edge of S. curriculus eys,and their gill raker was short and sparse. The main morphological characteristics of S.curriculus included:dorsal fin D.iii-7,pectoral fin P.i-14,anal fin A.iii-7-8,and ventral fin V.i-8.The dental formula was 2·4·5/4·4·2 or 2·4·4/4·4·2.Seven LDH enzyme bands and six MDH enzyme bands were detected in heart,eye,muscle,liver and kidney of S. curriculus. The numbers and activities of the enzyme bands in different tissue were different,showing obvious tissue specificity.There were also obvious differences in the same organs between different individuals.ConclusionThe tissue specificities expressed by isozymes are not only regulated by genetic genes, but also relate to the biochemical metabolic activities of various tissues.LDH isozymes from heart can be used as bioche-mical genetic marker of S.curriculus.