Characterization of SAP-1, a protein recruited by serum response factor to the c-fos serum response element

Cell. 1992 Feb 7;68(3):597-612. doi: 10.1016/0092-8674(92)90194-h.


We used a yeast genetic screen to isolate cDNAs that encode a protein, SRF accessory protein-1 (SAP-1), that is recruited to the c-fos serum response element (SRE) as part of a ternary complex that includes serum response factor (SRF). SAP-1 requires DNA-bound SRF for ternary complex formation and makes extensive DNA contacts to the 5' side of SRF, but does not bind DNA autonomously. Ternary complex formation by SAP-1 requires only the DNA-binding domain of SRF, which can be replaced by that of the related yeast protein MCM1. We isolated cDNAs encoding two forms of SAP-1 protein, SAP-1a and SAP-1b, which differ at their C termini. Both SAP-1 proteins contain three regions of striking homology with the elk-1 protein, including an N-terminal ets domain. Ternary complex formation by SAP-1 requires both the ets domain and a second conserved region 50 amino acids to its C-terminal side. SAP-1 has similar DNA binding properties to the previously characterized HeLa cell protein p62/TCF.

Publication types

  • Comparative Study

MeSH terms

  • Amino Acid Sequence
  • Base Sequence
  • Cloning, Molecular
  • DNA-Binding Proteins / chemistry
  • DNA-Binding Proteins / genetics*
  • DNA-Binding Proteins / metabolism
  • Fungal Proteins / chemistry
  • Fungal Proteins / genetics*
  • Gene Expression Regulation, Fungal*
  • Molecular Sequence Data
  • Nuclear Proteins / genetics*
  • Nuclear Proteins / metabolism
  • Open Reading Frames
  • Plasmids
  • Proto-Oncogene Proteins*
  • Retroviridae Proteins, Oncogenic / chemistry
  • Saccharomyces cerevisiae / genetics*
  • Sequence Alignment
  • Serum Response Factor
  • Transcription Factors*
  • ets-Domain Protein Elk-1
  • ets-Domain Protein Elk-4


  • DNA-Binding Proteins
  • Fungal Proteins
  • Nuclear Proteins
  • Proto-Oncogene Proteins
  • Retroviridae Proteins, Oncogenic
  • Serum Response Factor
  • Transcription Factors
  • ets-Domain Protein Elk-1
  • ets-Domain Protein Elk-4

Associated data

  • GENBANK/M84159
  • GENBANK/M84160
  • GENBANK/M85164
  • GENBANK/M85165
  • GENBANK/S72766
  • GENBANK/S72767
  • GENBANK/S72768
  • GENBANK/S72769
  • GENBANK/S72771
  • GENBANK/X63098