For COVID-19 vaccine updates, please review our information guide. For patient eligibility and scheduling availability, please visit VaccineTogetherNY.org.

Role of Blm and collaborating factors in recombination and survival following replication stress in Ustilago maydis.

TitleRole of Blm and collaborating factors in recombination and survival following replication stress in Ustilago maydis.
Publication TypeJournal Article
Year of Publication2009
AuthorsMao N, Kojic M, Holloman WK
JournalDNA Repair (Amst)
Volume8
Issue6
Pagination752-9
Date Published2009 Jun 4
ISSN1568-7864
KeywordsDNA Repair, DNA Replication, Exodeoxyribonucleases, Fungal Proteins, Hydroxyurea, Mutation, Nucleic Acid Synthesis Inhibitors, Rad51 Recombinase, Recombination, Genetic, RecQ Helicases, Ustilago
Abstract

Inactivation of the structural gene for the RecQ family member, BLM in human, Sgs1 in budding yeast, or Rqh1 in fission yeast leads to inappropriate recombination, chromosome abnormalities, and disturbed replication fork progression. Studies with yeasts have demonstrated that auxiliary gene functions can contribute in overlapping ways with Sgs1 or Rqh1 to circumvent or overcome lesions in DNA caused by certain genotoxic agents. In the combined absence of these functions, recombination-mediated processes lead to severe loss of fitness. Here we performed a genetic study to determine the role of the Ustilago maydis Blm homolog in DNA repair and in alleviating replication stress. We characterized the single mutant as well as double mutants additionally deleted of genes encoding Srs2, Fbh1, Mus81, or Exo1. Unlike yeasts, neither the blm srs2, blm exo1, nor blm mus81 double mutant exhibited extreme loss of fitness. Inactivation of Brh2, the BRCA2 homolog, suppressed toxicity to hydroxyurea caused by loss of Blm function. However, differential suppression by Brh2 derivatives lacking the canonical DNA-binding region suggests that the particular domain structure comprising this DNA-binding region may be instrumental in promoting the observed hydroxyurea toxicity.

DOI10.1016/j.dnarep.2009.02.006
Alternate JournalDNA Repair (Amst.)
PubMed ID19349216
PubMed Central IDPMC2693308
Grant ListGM42482 / GM / NIGMS NIH HHS / United States
R01 GM042482 / GM / NIGMS NIH HHS / United States
R01 GM042482-17 / GM / NIGMS NIH HHS / United States
R01 GM042482-18 / GM / NIGMS NIH HHS / United States

Weill Cornell Medicine Microbiology and Immunology 1300 York Avenue, Box 62 New York, NY 10065 Phone: (212) 746-6505 Fax: (212) 746-8587