Isolation of Zebrafish Balbiani Bodies for Proteomic Analysis

Proteomic characterization of isolated organelles can provide insight into the functional components of the structure and novel targets for further testing. Germplasm in developing oocytes is difficult to isolate for protein identification because not all types of germplasm are stable outside of the cytoplasm. In zebrafish, the Balbiani body forms a proteinaceous aggregate that contains the germplasm and we found is stable outside of the oocyte. Here we present a manual isolation protocol that collects intact Balbiani bodies from stage I zebrafish oocytes. We lysed oocytes by passing them through a syringe, and then used a fine injection needle to wick up Balbiani bodies by capillary action with minimal buffer solution. Using this protocol we collected sufficient material for proteomic analysis of the zebrafish Balbiani body.