Structure and DNA-binding sites of the SWI1 AT-rich interaction domain (ARID) suggest determinants for sequence-specific DNA recognition

J Biol Chem. 2004 Apr 16;279(16):16670-6. doi: 10.1074/jbc.M312115200. Epub 2004 Jan 13.


ARID (AT-rich interaction domain) is a homologous family of DNA-binding domains that occur in DNA-binding proteins from a wide variety of species, ranging from yeast to nematodes, insects, mammals, and plants. SWI1, a member of the SWI/SNF protein complex that is involved in chromatin remodeling during transcription, contains the ARID motif. The ARID domain of human SWI1 (also known as p270) does not select for a specific DNA sequence from a random sequence pool. The lack of sequence specificity shown by the SWI1 ARID domain stands in contrast to the other characterized ARID domains, which recognize specific AT-rich sequences. We have solved the three-dimensional structure of human SWI1 ARID using solution NMR methods. In addition, we have characterized nonspecific DNA binding by the SWI1 ARID domain. Results from this study indicate that a flexible, long, internal loop in the ARID motif is likely to be important for sequence-specific DNA recognition. The structure of the human SWI1 ARID domain also represents a distinct structural subfamily. Studies of ARID indicate that the boundary of DNA binding structural and functional domains can extend beyond the sequence homologous region in a homologous family of proteins. Structural studies of homologous domains such as the ARID family of DNA-binding domains should provide information to better predict the boundary of structural and functional domains in structural genomic studies.

Publication types

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

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Binding Sites
  • DNA / genetics
  • DNA / metabolism
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism*
  • Humans
  • Models, Molecular
  • Molecular Sequence Data
  • Protein Binding
  • Protein Conformation
  • Protein Structure, Tertiary
  • Sequence Alignment
  • Transcription Factors / genetics
  • Transcription Factors / metabolism*


  • DNA-Binding Proteins
  • Transcription Factors
  • DNA