The HMG domain of lymphoid enhancer factor 1 bends DNA and facilitates assembly of functional nucleoprotein structures

Cell. 1992 Apr 3;69(1):185-95. doi: 10.1016/0092-8674(92)90129-z.

Abstract

The high mobility group (HMG) domain is a DNA-binding motif that is associated with several eukaryotic regulatory proteins, including the lymphoid enhancer-binding factor LEF-1 and the testis-determining factor SRY. Here, we provide evidence that DNA binding by the HMG domain of LEF-1 involves primarily minor groove contacts and induces a bend of approximately 130 degrees in the DNA helix. Bending was also found to accompany sequence-specific DNA binding by the SRY-HMG domain. Examining possible regulatory roles of HMG domain-induced DNA bends, we found that LEF-1 can function in a manner similar to bacterial integration host factor and facilitate communication between widely separated protein-binding sites in a recombination assay. Together with the previous observation that LEF-1 by itself is unable to augment basal promoter activity, these data suggest that HMG domain proteins can serve as "architectural" elements in the assembly of higher-order nucleoprotein structures.

Publication types

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

MeSH terms

  • Base Sequence
  • Binding Sites / genetics
  • DNA / metabolism*
  • DNA Nucleotidyltransferases / metabolism
  • DNA-Binding Proteins / metabolism*
  • High Mobility Group Proteins / metabolism*
  • Humans
  • Integrases
  • Lymphoid Enhancer-Binding Factor 1
  • Molecular Sequence Data
  • Nuclear Proteins / metabolism*
  • Nucleic Acid Conformation*
  • Nucleoproteins / metabolism*
  • Recombination, Genetic / genetics
  • Sex-Determining Region Y Protein
  • Transcription Factors*

Substances

  • DNA-Binding Proteins
  • High Mobility Group Proteins
  • LEF1 protein, human
  • Lymphoid Enhancer-Binding Factor 1
  • Nuclear Proteins
  • Nucleoproteins
  • SRY protein, human
  • Sex-Determining Region Y Protein
  • Transcription Factors
  • DNA
  • DNA Nucleotidyltransferases
  • Integrases