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bioRxiv · 10.1101/2021.11.03.466203

Mis6/CENP-I maintains CENP-A nucleosomes against centromeric non-coding transcription during mitosis

Hirai, H.·Shogaki, Y.·Sato, M.
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Abstract

Centromeres are established by nucleosomes containing the histone H3 variant CENP-A. CENP-A is recruited to centromeres by the Mis18-HJURP machinery. During mitosis, CENP-A recruitment ceases, implying the necessity of CENP-A maintenance at centromeres, although the exact underlying mechanism remains elusive. Herein, we show that the kinetochore protein Mis6 (CENP-I) retains CENP-A during mitosis in fission yeast. Eliminating Mis6 during mitosis caused immediate loss of pre-existing CENP-A at centromeres. CENP-A loss occurred due to the transcriptional upregulation of non-coding RNAs at the central core region of centromeres, as confirmed by the observation RNA polymerase II inhibition preventing CENP-A loss from centromeres in the mis6 mutant. Thus, we concluded that Mis6 blocks the indiscriminate transcription of non-coding RNAs at the core centromere, thereby retaining the epigenetic inheritance of CENP-A during mitosis.

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Hirai, H., Shogaki, Y., Sato, M.. 2021-11-04. Mis6/CENP-I maintains CENP-A nucleosomes against centromeric non-coding transcription during mitosis. https://doi.org/10.1101/2021.11.03.466203

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