Arginine shortage induces replication stress and confers genotoxic resistance by inhibiting histone H4 translation and promoting PCNA ubiquitination.

The arginine dependency of cancer cells creates metabolic vulnerability. In this study, we examine the impact of arginine availability on DNA replication and genotoxicity resistance. Using DNA combing assays, we find that limiting extracellular arginine results in the arrest of cancer cells at S phase and a slowing or stalling of DNA replication. The translation of new histone H4 is arginine dependent and influences DNA replication. Increased proliferating cell nuclear antigen (PCNA) occupancy and helicase-like transcription factor (HLTF)-catalyzed PCNA K63-linked polyubiquitination protect arginine-starved cells from DNA damage. Arginine-deprived cancer cells display tolerance to genotoxicity in a PCNA K63-linked polyubiquitination-dependent manner. Our findings highlight the crucial role of extracellular arginine in nutrient-regulated DNA replication and provide potential avenues for the development of cancer treatments. [Display omitted] • Arginine shortage halts H4 histone synthesis, stalling DNA replication • Fork stalling creates vulnerability of nascent DNA strands to DNA2-mediated degradation • Cells respond to arginine deprivation by HLTF-mediated K63-polyubiquitination of PCNA • HLTF and PCNA polyubiquitylation protect arginine-starved cells from DNA damage agents Wang et al. find that arginine shortage can temporarily place DNA replication on hold via inhibiting histone H4 translation and stalling fork movement. They show that this is associated with HLTF-mediated K63-linked polyubiquitination of PCNA, which increases PCNA's presence on nascent DNA strands, and helps cells tolerate DNA damage. [ABSTRACT FROM AUTHOR]