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Direct recruitment of Mis18 to interphase spindle poles promotes CENP-A chromatin assembly.

ABSTRACT: CENP-A chromatin specifies mammalian centromere identity, and its chaperone HJURP replenishes CENP-A when recruited by the Mis18 complex (Mis18C) via M18BP/KNL2 to CENP-C at kinetochores during interphase. However, the Mis18C recruitment mechanism remains unresolved in species lacking M18BP1, such as fission yeast. Fission yeast centromeres cluster at G2 spindle pole bodies (SPBs) when CENP-ACnp1 is replenished and where Mis18C also localizes. We show that SPBs play an unexpected role in concentrating Mis18C near centromeres through the recruitment of Mis18 by direct binding to the major SPB LInker of Nucleoskeleton and Cytoskeleton (LINC) complex component Sad1. Mis18 recruitment by Sad1 is important for CENP-ACnp1 chromatin establishment and acts in parallel with a CENP-C-mediated Mis18C recruitment pathway to maintain centromeric CENP-ACnp1, but is independent of Sad1-mediated centromere clustering. SPBs therefore provide a non-chromosomal scaffold for both Mis18C recruitment and centromere clustering during G2. This centromere-independent Mis18-SPB recruitment provides a mechanism that governs de novo CENP-ACnp1 chromatin assembly by the proximity of appropriate sequences to SPBs and highlights how nuclear spatial organization influences centromere identity.

INSTRUMENT(S): Orbitrap Fusion Lumos

ORGANISM(S): Schizosaccharomyces Pombe 927

TISSUE(S): Cell Suspension Culture, Cell Culture

SUBMITTER: Nitobe London

LAB HEAD: Robin Allshire

PROVIDER: PXD045191 | Pride | 2023-09-18

REPOSITORIES: Pride

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			Action	DRS
	London_etal_2023_CEN_SPB_Interaction_3.7z	Other
	London_etal_2023_CEN_SPB_interaction_1.7z	Other
	London_etal_2023_CEN_SPB_interaction_2.7z	Other
	London_etal_2023_Sad1_3V5_Rep1.raw	Raw
	London_etal_2023_Sad1_3V5_Rep2.raw	Raw

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