INVESTIGATION OF NUCLEAR LAMINA IN TETRAHY- MENA THERMOPHILA
Chen Bin Cai Shu-tao Zhai Zhong-he (Department of Biology, Peking University, Beijing 100871
The nuclear lamina in the nuclei of Tetrahymena thermophila was investigated using the techniques of selective extraction and embedment-free electron microscopy, as well as immunofluorescence staining. By means of immunoblotting and protein isolating, the lamina was found to consist mainly of a 66 KD polypeptide. While rabbit-anti-lamins polyclonal antibodies crossreacted with this protein, neither mu-rine-anti-lamin AC mAB C 23 nor murine-anti-lamin 1 mAB 223 showed positive reaction with it. It was also demonstrated that the lamin is not so rich as that in mammalian cells. The existence of lamina in T. thermophila, a unicellular organism, seems to show that the lamina is a basic characteristic structure of eu-karyotic cells, and that the function of the lamina may not be limited to the process of breakdown and reconstitution of nuclear envelope during mitosis.