posted on 2023-05-18, 04:24authored byWong, LH, Kate Brettingham-MooreKate Brettingham-Moore, Chan, L, Quach, JM, Anderson, MA, Northrop, EL, Hannan, R, Saffery, R, Shaw, ML, Williams, E, Choo, KHA
The centromere is a complex structure, the components and assembly pathway of which remain inadequately defined. Here, we demonstrate that centromeric α-satellite RNA and proteins CENPC1 and INCENP accumulate in the human interphase nucleolus in an RNA polymerase I-dependent manner. The nucleolar targeting of CENPC1 and INCENP requires α-satellite RNA, as evident from the delocalization of both proteins from the nucleolus in RNase-treated cells, and the nucleolar relocalization of these proteins following α-satellite RNA replenishment in these cells. Using protein truncation and in vitro mutagenesis, we have identified the nucleolar localization sequences on CENPC1 and INCENP. We present evidence that CENPC1 is an RNA-associating protein that binds α-satellite RNA by an in vitro binding assay. Using chromatin immunoprecipitation, RNase treatment, and "RNA replenishment" experiments, we show that α-satellite RNA is a key component in the assembly of CENPC1, INCENP, and survivin (an INCENP-interacting protein) at the metaphase centromere. Our data suggest that centromere satellite RNA directly facilitates the accumulation and assembly of centromere-specific nucleoprotein components at the nucleolus and mitotic centromere, and that the sequestration of these components in the interphase nucleolus provides a regulatory mechanism for their timely release into the nucleoplasm for kinetochore assembly at the onset of mitosis.
History
Publication title
Genome Research
Volume
17
Issue
8
Pagination
1146-1160
ISSN
1088-9051
Department/School
Menzies Institute for Medical Research
Publisher
Cold Spring Harbor Lab Press
Place of publication
Publications Dept, 500 Sunnyside Blvd, Woodbury, USA, Ny, 11797-2924