Yeast Origin Recognition Complex Is Involved in DNA Replication and Transcriptional Silencing

Nature. 1993 Nov 4;366(6450):87-9. doi: 10.1038/366087a0.

Abstract

The HMR E silencer represses transcription of silent mating-type genes in the budding yeast Saccharomyces cerevisiae and contains three redundant regulatory elements A, E and B (ref. 1). The A element contains the 11 base pair consensus sequence that is essential for the firing of DNA replication origins. A multisubunit protein called the origin recognition complex (ORC) binds specifically to this consensus sequence within yeast origins in vitro and in vivo. We isolated mutants in A element-mediated silencing and report here that one of the genes we identified, RRR1, encodes ORC2, the 72K subunit of ORC. RRR1/ORC2 is an essential gene, but the rrr1-316 allele, which is viable, is defective in the replication of nuclear DNA and the maintenance of the 2-microns episomal DNA. This is, to our knowledge, the first genetic evidence that ORC is involved in DNA replication and silencing.

MeSH terms

  • Amino Acid Sequence
  • Base Sequence
  • DNA Replication / physiology*
  • DNA, Fungal / genetics*
  • DNA-Binding Proteins*
  • Fungal Proteins / genetics
  • Fungal Proteins / physiology*
  • Genetic Complementation Test
  • Molecular Sequence Data
  • Mutation
  • Origin Recognition Complex
  • Regulatory Sequences, Nucleic Acid / physiology
  • Repressor Proteins / genetics
  • Repressor Proteins / physiology*
  • Saccharomyces cerevisiae / genetics*
  • Saccharomyces cerevisiae Proteins

Substances

  • DNA, Fungal
  • DNA-Binding Proteins
  • Fungal Proteins
  • ORC2 protein, S cerevisiae
  • Origin Recognition Complex
  • Repressor Proteins
  • Saccharomyces cerevisiae Proteins

Associated data

  • GENBANK/Z21817