Abstract:Immunofluorescence staining with anti-animal NuMA antibodies revealed the existence of NuMA protein-like components in carrot ( Daucus carom L. ) suspension cells and the NuMA-like proteins exhibited regular distribution during mitosis. Furthermore, immunofluorescence staining of the nuclei after cell extraction revealed that the NuMA-like proteins were components of nuclear matrix proteins and the nuclear matrix changed obviously during mitosis. Western blot with anti-animal NuMA antibodies identified two positive bands of the nuclear matrix components with molecular weight of 74 kD and 76 kD. Using selective extraction and diethylene glycol distearate (DGD) embedment and embedment-free electron microscopy, the well-organized nuclear matrix network was observed in interphase carrot cells but not in cells during metosis. These results suggest that NuMA-like proteins are components of nuclear matrix, and are closely related with mitosis.