Nucleolus transformation in mouse antral follicles: Distribution of coilin and components of RNA-polymerase I complex

This study is the next step in the examination of the nucleolus transformation in growing oocytes from mouse multilayer follicles (Pochukalina and Parfenov, 2006). Here, we present our results on the structural organization and molecular composition of postnucleoli in oocytes isolated from mouse antral folicules. Using light and electron microscopic immunocytochemistry, we examined the dynamics of the distribution of molecular components of rRNA synthesis and the processing in postnucleoli. Considerable changes were revealed in the RNA polymerase I distribution and its colocalization with coilin on the periphery of postnucleoli. The putative role of coilin in complex formation with ribosomal RNA synthesis/processing components is discussed.