RNAi-Based Suppressor Screens Reveal Genetic Interactions Between the CRL2 LRR-1 E3-Ligase and the DNA Replication Machinery in Caenorhabditis elegans

Batool Ossareh-Nazari (1) , Anthi Katsiarimpa (1) , Jorge Merlet (2, 1) , Lionel Pintard (1)

1 IJM (UMR_7592) - Institut Jacques Monod
2 LBD-E03 - C.elegans Hérédité et Développement = C.elegans heredity and development

Cullin-RING E3-Ligases (CRLs), the largest family of E3 ubiquitin-Ligases, regulate diverse cellular processes by promoting ubiquitination of target proteins. The evolutionarily conserved Leucine Rich Repeat protein 1 (LRR-1) is a substrate-recognition subunit of a CRL2 LRR-1 E3-ligase. Here we provide genetic evidence supporting a role of this E3-enzyme in the maintenance of DNA replication integrity in Caenorhabditis elegans. Through RNAi-based suppressor screens of lrr-1(0) and cul-2(or209ts) mutants, we identified two genes encoding components of the GINS complex, which is part of the Cdc45-MCM-GINS (CMG) replicative helicase, as well as CDC-7 and MUS-101, which drives the assembly of the CMG helicase during DNA replication. In addition, we identified the core components of the ATR/ATL-1 DNA replication checkpoint pathway (MUS-101, ATL-1, CLSP-1, CHK-1). These results suggest that the CRL2 LRR-1 E3-ligase acts to modify or degrade factor(s) that would otherwise misregulate the replisome, eventually leading to the activation of the DNA replication checkpoint.

Keywords: Mutant Screen Report; Cullin-RING E3-Ligases; DNA replication; C. elegans

Domains: Genomics [q-bio.GN]

Batool Ossareh-Nazari, Anthi Katsiarimpa, Jorge Merlet, Lionel Pintard. RNAi-Based Suppressor Screens Reveal Genetic Interactions Between the CRL2 LRR-1 E3-Ligase and the DNA Replication Machinery in Caenorhabditis elegans. G3, 2016, 6 (10), pp.3431-3442. ⟨10.1534/g3.116.033043⟩. ⟨hal-01404139⟩