DIFFERENCE IN THE DISTRIBUTION AND CONTENT OF NUCLEOLAR PROTEIN B 23 BETWEEN INTERPHASE AND MITOTIC HELA CELLS
Yang Xinlin Li Shi Wang Yongchao (Biology Department of Beijing Normal University, 100875)
Protein B 23 is one of the two major protein components in eukaryocytic nuc-leolus. Previous studies indicate that the cellular content and distribution of protein B 23 are correlated with the synthetic rate of ribosomal RNA (rRNA) and cell growth. It is more abundant in tumor and growing cells than in normal resting cells. It may translocate from nucleolus to nuc-leoplasm after serum deprivation, or after being treated with RNA inhibitors such as actinomycin D, toyocamycin, or doxo-rubicin. In order to search for the role of protein B 23 in cell division, using an anti-B 23 monoclonal antibody, we detect the cellular content and distribution of protein B 23 in interphase and mitotic HeLa cells, respectively. Two microtubule drugs, col-cemid and taxol, are used to arrest the mitotic cells.The results show the cellular content of protein B 23 in mitotic cells is much higher than that in interphase cells. The intracellular distribution of protein B 23 in mitotic cells is distinguished from that in interphase cells too.