A Yeast and a Human CCAAT-binding Protein Have Heterologous Subunits That Are Functionally Interchangeable

Cell. 1988 Apr 8;53(1):25-35. doi: 10.1016/0092-8674(88)90484-9.


The S. cerevisiae HAP2 and HAP3 gene products have been shown to recognize CCAAT-containing transcription elements as a HAP2/HAP3 multisubunit heterologous complex, or heteromer. Recently, we have demonstrated that the human sequence-specific DNA-binding protein, CP1, also recognizes CCAAT-containing transcription elements as a heteromer. Mammalian cells contain at least three distinct CCAAT-binding proteins, all of which appear to be multisubunit complexes composed of heterologous subunits. One of these proteins, CP1, has DNA-binding properties that are virtually identical to the yeast HAP2/HAP3 complex. These two proteins bind to the same target sequences, make the same DNA contacts, and are affected in a similar manner by mutations in the CCAAT element. Most surprisingly, the subunits of CP1 and HAP2/HAP3 are functionally interchangeable. That is, the yeast/human hybrid complexes that are formed retain the ability to specifically recognize CCAAT elements.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Biological Evolution
  • CCAAT-Enhancer-Binding Proteins
  • DNA-Binding Proteins / metabolism*
  • Genes*
  • Genes, Fungal
  • HeLa Cells / metabolism
  • Humans
  • Macromolecular Substances
  • Methylation
  • Oligodeoxyribonucleotides / metabolism*
  • Plasmids
  • Saccharomyces cerevisiae / genetics*
  • Saccharomyces cerevisiae / metabolism
  • Species Specificity


  • CCAAT-Enhancer-Binding Proteins
  • DNA-Binding Proteins
  • Macromolecular Substances
  • Oligodeoxyribonucleotides