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RNA-DNA hybrids prevent resection at dysfunctional telomeres

ABSTRACT: At critically short telomeres TERRA RNA-DNA hybrids become stabilized and drive homology-directed repair (HDR) to delay replicative senescence. However, even at long- and intermediate-length telomeres, not subject to HDR, transient TERRA RNA-DNA hybrids form, suggestive of additional roles. Here, we report that hybrids at telomeres prevent resection by the Exo1 nuclease when telomeres become non-functional. We employed the well-characterized cdc13-1 allele, where telomere resection can be induced in a temperature dependent manner, to demonstrate that ssDNA generation at telomeres is either prevented or augmented when RNA-DNA hybrids are stabilized or destabilized, respectively. The viability of cdc13-1 cells is affected by the presence or absence of hybrids accordingly. These results give insights into an additional role of TERRA at dysfunctional telomeres suggesting that it not only affects replicative senescence rates through HDR activation at critically short telomeres, but may also affect resection rates at intermediate length telomeres in pre-senescent cells.

INSTRUMENT(S): Q Exactive

ORGANISM(S): Saccharomyces Cerevisiae (baker's Yeast)

SUBMITTER: F Butter

LAB HEAD: Falk Butter

PROVIDER: PXD034986 | Pride | 2023-01-18

REPOSITORIES: Pride

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			Action	DRS
	20220204_SFB1_FBU_MW_collabPires_EV_1.raw	Raw
	20220204_SFB1_FBU_MW_collabPires_EV_2.raw	Raw
	20220204_SFB1_FBU_MW_collabPires_EV_3.raw	Raw
	20220204_SFB1_FBU_MW_collabPires_EV_4.raw	Raw
	20220204_SFB1_FBU_MW_collabPires_EV_5.raw	Raw

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