Protein expression and subcellular distribution of centriolar component SAS-6 in mouse oocyte meiosis

Abstract

Objective To study the expression and subcellular distribution pattern of centriolar protein SAS-6 during meiosis of mouse oocytes. Methods Immunefluorescence was conducted to analyze the subcellular distribution pattern of SAS-6 in Chinese hamster ovary cell line(CHO cell) during mitosis. Western blot was applied to detect the protein expression of SAS-6 in mouse oocyte meiosis. Immunofluorescence microscopy carried out to determine the subcellular distribution of SAS-6 and its association with microtubule organizing centers (MTOCs) and in vesicles during the oocyte meiosis. Results SAS-6 was colocalized with Pericentrin on spindle poles during the mitotic process in somatic cells. In mouse oocytes, SAS-6 was stably and consistently expressed at all stages of meiosis and specifically aggregated on GM130-positive vesicles, but not in MTOCs. The results suggested that centriolar protein SAS-6 was still expressed in oocytes lacking centrosomes, and localized in GM130-positive vesicles but expressed on percientrin-positive MTOCs. Conclusions SAS-6 may play a role in spindle cortical migration through regulating vesicles during oocyte meiosis.

Keywords

• spindle assembly abnormal protein 6|oocyte|microtubule organizing centers|vesicle|spindle migration