GSBS Student Publications

Title

Efficient repair of large DNA loops in Saccharomyces cerevisiae

UMMS Affiliation

Graduate School of Biomedical Sciences; Department of Biochemistry and Molecular Pharmacology

Date

10-16-2001

Document Type

Article

Medical Subject Headings

Base Pair Mismatch; Base Sequence; *DNA Repair; DNA, Fungal; Genes, Fungal; Mutation; Nucleic Acid Conformation; Nucleic Acid Heteroduplexes; Saccharomyces cerevisiae

Disciplines

Life Sciences | Medicine and Health Sciences

Abstract

Small looped mispairs are efficiently corrected by mismatch repair. The situation with larger loops is less clear. Repair activity on large loops has been reported as anywhere from very low to quite efficient. There is also uncertainty about how many loop repair activities exist and whether any are conserved. To help address these issues, we studied large loop repair in Saccharomyces cerevisiae using in vivo and in vitro assays. Transformation of heteroduplexes containing 1, 16 or 38 nt loops led to >90% repair for all three substrates. Repair of the 38 base loop occurred independently of mutations in key genes for mismatch repair (MR) and nucleotide excision repair (NER), unlike other reported loop repair functions in yeast. Correction of the 16 base loop was mostly independent of MR, indicating that large loop repair predominates for this size heterology. Similarities between mammalian and yeast large loop repair were suggested by the inhibitory effects of loop secondary structure and by the role of defined nicks on the relative proportions of loop removal and loop retention products. These observations indicate a robust large loop repair pathway in yeast, distinct from MR and NER, and conserved in mammals.

Rights and Permissions

Citation: Nucleic Acids Res. 2001 Oct 15;29(20):4134-43.

Related Resources

Link to article in PubMed

Journal Title

Nucleic acids research

PubMed ID

11600702