[Nucleolus transformation in oocytes of mouse antral follicles. Revealing of coilin and RNA polymerase I complex components].

This study is the continuation of our previous investigation of the nucleolus transformation in growing oocytes from mouse multilayer follicles (Pochukalina, Parfenov, 2006). Here in the present research we have examined the features of organization and molecular composition of nucleolus like body, or postnucleolus, in two groups of oocytes with different chromatin configuration from mouse antral follicles. Using light and electron immunocytochemistry, we have defined the dynamics of ribosomal RNA synthesis and processing molecular component distribution in postnucleolus. Considerable changes in RNA polymerase I distribution and its colocalization with coilin at the periphery of postnucleolus were revealed. Putative role of coilin in formation of complexes with ribosomal RNA synthesis/processing components is discussed.