Abstract: To study the sub-localization of Zwint-1 wild type and variant(Zwint-1v) in different cell cycles of HeLa cells. METHODS：HeLa cells were synchronized using thymidine double-block method. The sub-localization of Zwint-1 wild type and Zwint-1v were identified by fluorescence microscope after transfection and indirect immunofluorescence. RESULTS：In interphase of HeLa cells，Zwint-1 wild type was localized in the cytoplasm， while Zwint-1v were in nucleus. In mitotic phase，Zwint-1 wild type and Zwint-1v were found on the spindle and centromere. Zwint-1v was closer to the nucleus than the wild type. CONCLUSION：Zwint-1 wild type and Zwint-1v during cell cycle have different sub-localization.

Key words: Zwint-1, Zwint-1v, mitotic checkpoint, localization