Shortage of dNTPs underlies altered replication dynamics and DNA breakage in the absence of the APC/C cofactor Cdh1

Javier Garzón, Rubén Rodríguez, Ziqing Kong, Andrei Chabes, Sara Rodríguez-Acebes, Juan Méndez, Sergio Moreno, Irene García-Higuera

Research output: Contribution to journalArticle

10 Citations (Scopus)
7 Downloads (Pure)

Abstract

The APC/C-Cdh1 ubiquitin-ligase complex targets cell cycle regulators for proteosomal degradation and helps prevent tumor development and accumulation of chromosomal aberrations. Replication stress has been proposed to be the main driver of genomic instability in the absence of Cdh1, but the real contribution of APC/C-Cdh1 to efficient replication, especially in normal cells, remains unclear. Here we show that, in primary MEFs, acute depletion or permanent ablation of Cdh1 slowed down replication fork movement and increased origin activity. Partial inhibition of origin firing does not accelerate replication forks, suggesting that fork progression is intrinsically limited in the absence of Cdh1. Moreover, exogenous supply of nucleotide precursors, or ectopic overexpression of RRM2, the regulatory subunit of Ribonucleotide Reductase, restore replication efficiency, indicating that dNTP availability could be impaired upon Cdh1 loss. Indeed, we found reduced dNTP levels in Cdh1-deficient MEFs. Importantly, DNA breakage is also significantly alleviated by increasing intracellular dNTP pools, strongly suggesting that genomic instability is the result of aberrant replication. These observations highlight the relevance of APC/C-Cdh1 activity during G1 to ensure an adequate supply of dNTPs to the replisome, prevent replication stress and the resulting chromosomal breaks and, ultimately, suppress tumorigenesis.
Original languageEnglish
Pages (from-to)5808-5818
Number of pages11
JournalOncogene
Volume63
Issue number42
Early online date12 Jun 2017
DOIs
Publication statusPublished - 19 Oct 2017

Keywords

  • APC/C
  • Cdh1
  • RRM2
  • dNTPs

Fingerprint Dive into the research topics of 'Shortage of dNTPs underlies altered replication dynamics and DNA breakage in the absence of the APC/C cofactor Cdh1'. Together they form a unique fingerprint.

Cite this