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Unexpected conformational variations of the human centromeric chromatin complex.

ABSTRACT: We combined classical salt fractionation with chromatin immunoprecipitation to recover human centromeric chromatin under native conditions. We found that >85% of the total centromeric chromatin is insoluble under conditions typically used for native chromatin extraction. To map both soluble and insoluble chromatin in situ, we combined CUT&RUN (cleavage under targets and release using nuclease), a targeted nuclease method, with salt fractionation. Using this approach, we observed unexpected structural and conformational variations of centromere protein A (CENP-A)-containing complexes on different ?-satellite dimeric units within highly homogenous arrays. Our results suggest that slight ?-satellite sequence differences control the structure and occupancy of the associated centromeric chromatin complex.

SUBMITTER: Thakur J

PROVIDER: S-EPMC5828391 | biostudies-literature | 2018 Jan

REPOSITORIES: biostudies-literature

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Unexpected conformational variations of the human centromeric chromatin complex.

Thakur Jitendra J Henikoff Steven S

Genes & development 20180131 1

We combined classical salt fractionation with chromatin immunoprecipitation to recover human centromeric chromatin under native conditions. We found that >85% of the total centromeric chromatin is insoluble under conditions typically used for native chromatin extraction. To map both soluble and insoluble chromatin in situ, we combined CUT&RUN (cleavage under targets and release using nuclease), a targeted nuclease method, with salt fractionation. Using this approach, we observed unexpected struc ...[more]

PMID: 29386331

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Unexpected conformational variations of the human centromeric chromatin complex

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