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Telomere maintenance through recruitment of internal genomic regions.

ABSTRACT: Cells surviving crisis are often tumorigenic and their telomeres are commonly maintained through the reactivation of telomerase. However, surviving cells occasionally activate a recombination-based mechanism called alternative lengthening of telomeres (ALT). Here we establish stably maintained survivors in telomerase-deleted Caenorhabditis elegans that escape from sterility by activating ALT. ALT survivors trans-duplicate an internal genomic region, which is already cis-duplicated to chromosome ends, across the telomeres of all chromosomes. These 'Template for ALT' (TALT) regions consist of a block of genomic DNA flanked by telomere-like sequences, and are different between two genetic background. We establish a model that an ancestral duplication of a donor TALT region to a proximal telomere region forms a genomic reservoir ready to be incorporated into telomeres on ALT activation.

SUBMITTER: Seo B

PROVIDER: S-EPMC4595603 | biostudies-literature | 2015 Sep

REPOSITORIES: biostudies-literature

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Telomere maintenance through recruitment of internal genomic regions.

Seo Beomseok B Kim Chuna C Hills Mark M Sung Sanghyun S Kim Hyesook H Kim Eunkyeong E Lim Daisy S DS Oh Hyun-Seok HS Choi Rachael Mi Jung RMJ Chun Jongsik J Shim Jaegal J Lee Junho J

Nature communications 20150918

Cells surviving crisis are often tumorigenic and their telomeres are commonly maintained through the reactivation of telomerase. However, surviving cells occasionally activate a recombination-based mechanism called alternative lengthening of telomeres (ALT). Here we establish stably maintained survivors in telomerase-deleted Caenorhabditis elegans that escape from sterility by activating ALT. ALT survivors trans-duplicate an internal genomic region, which is already cis-duplicated to chromosome ...[more]

PMID: 26382656

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