Biopolym. Cell. 2015; 31(6):422-428.
Structure and Function of Biopolymers
Association of Rictor with chromosomes during mitosis in MCF7 cells
1Malanchuk O. M.
  1. Institute of Molecular Biology and Genetics, NAS of Ukraine
    150, Akademika Zabolotnoho Str., Kyiv, Ukraine, 03680


The mTOR kinase forms two multicomponent protein complexes (mTORC1 and mTORC2), where protein Rictor is a unique component of mTORC2. These two complexes differ both structurally and functionally and transmit signals to distinct downstream substrates. In contrast to mTORC1, comparatively little is known about functioning and regulation of mTORC2 and its components. Aim. To analyze of the particularity of Rictor subcellular localization in MCF7 cells. Methods. Immunofluorescence assay using confocal microscopy was applied. Results. Analysis of Rictor localization with anti N-terminal mAb revealed a different pattern of immunostaining in cells that was depended on cell cycle phase. For the first time it was shown that Rictor is at the exposed edge of condensed chromatin pool in MCF7 cells. Furthermore Z-stacking of cells revealed that character of association depends on mitosis phases. Conclusions. Our novel findings add to our understanding of functioning of both Rictor and mTORC2 in cell cycle progression.
Keywords: Rictor, mTORC2, immunofluorescence, subcellular localization, mitosis


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