The POU domain is a bipartite DNA-binding structure

Nature. 1988 Dec 8;336(6199):601-4. doi: 10.1038/336601a0.


The POU domain (pronounced 'pow') is a highly charged 155-162-amino-acid (aa) region of sequence similarity contained within three mammalian transcription factors. Pt-1 (ref. 2), Oct-1 (ref. 3) and Oct-2 (ref. 4), and the product of the nematode gene unc-86 (ref. 5) which is involved in determining neural cell lineage. This domain consists of two subdomains, a C-terminal homoeo domain and an N-terminal POU-specific region separated by a short nonconserved linker; the sequence relationship shows that the POU homoeo domains form a distinct POU-related family. In the ubiquitous and lymphoid-specific octamer-motif binding proteins Oct-1 and Oct-2, the POU domain is sufficient for sequence-specific DNA binding. Homoeobox domains contain a helix-turn-helix DNA-binding motif, first identified in bacterial repressors. The helix-turn-helix region of the POU domain is important for DNA binding and, in other classes of homoeo-containing proteins, the entire homoeo domain is sufficient for DNA binding; thus the new POU-specific region could be involved in other functions such as protein-protein interactions. Nevertheless, we show here that in fact the POU domain is a novel bipartite DNA-binding structure in which the POU homoeo and POU-specific regions form two subdomains that are both required for DNA binding but are held together by a flexible linker.

Publication types

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

MeSH terms

  • Base Sequence
  • DNA / metabolism*
  • Genes, Homeobox
  • Genes, Viral
  • Molecular Sequence Data
  • Mutation
  • Simian virus 40 / genetics
  • Simplexvirus / genetics
  • Transcription Factors / genetics*
  • Transcription Factors / metabolism


  • Transcription Factors
  • DNA