Identification of molecular markers in gill cells and hemocytes of crayfish Cherax quadricarinatus
Being rich in a large number of hemocytes,the gills of crustacean play an important role in the regula-tion of hemocyte homeostasis and immune defense.Molecular markers to distinguish gill cells from hemocytes are re-quired for the study of hemocytes in gill.In this study,we compared the protein profiles of gill cells and hemocytes of crayfish Cherax quadricarinatus using SDS-PAGE electrophoresis.Eight candidate proteins were identified from tissue-specific bands by LC-MS/MS.The expression of these candidate proteins in gill and hemocytes were analyzed by quantitative real-time fluorescence PCR(qRT-PCR).The transcription of vacuolar-H+-ATPase subunit C(V-H+-ATPase)in gill was 53.3 folds of that in hemocytes.Whereas,the transcription of alpha-2-macroglobulin(α2M)and vitelline membrane outer layer protein I-like protein(VMO-Ia)in hemocytes was 10.3 folds and 10.9 folds of that in gills,respectively.Western blot and immunofluorescence analysis confirmed that V-H+-ATPase and VMO-Ia proteins were specifically expressed in gill cells and hemocytes,respectively.Therefore,V-H+-ATPase and VMO-Ia can be used as molecular markers to distinguish crayfish gill cells from hemocytes and may also provide a reference for the study of gill hemocytes in other decapod crustaceans.