The Arabidopsis Athb-8, -9 and -14 genes are members of a small gene family coding for highly related HD-ZIP proteins

Plant Mol Biol. 1998 Nov 1;38(4):609-22. doi: 10.1023/a:1006016319613.


We report the isolation and characterization of two Arabidopsis homeobox genes highly related to the Athb-8 gene. The full-length cDNAs encode proteins of 841 and 852 amino acids which we have designated Athb-9 and -14, respectively. Athb-8, -9 and -14 are members of a small family of HD-Zip proteins (HD-ZIP III) characterized by a HD-Zip motif confined to the N-terminus of the polypeptide. The spatial organization of the HD-Zip domain of Athb-8, -9 and -14 is different from that of the Athb-1 (a member of the HD-ZIP I family) and Athb-2 (a member of the HD-ZIP II family) HD-Zip domains. DNA binding analysis performed with random-sequence DNA templates showed that the Athb-9 HD-Zip (HD-Zip-9) domain, but not the Athb-9 HD alone, binds to DNA. The HD-Zip-9 domain recognizes a 11 bp pseudopalindromic sequence (GTAAT(G/C)ATTAC), as determined by selecting high-affinity binding sites from random-sequence DNA. Moreover, gel retardation assays demonstrated that the HD-Zip-9 domain binds to DNA as a dimer. These data support the notion that the HD-ZIP III domain interacts with DNA recognition elements in a fashion similar to the HD-ZIP I and II domains.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Arabidopsis / genetics*
  • Arabidopsis / metabolism
  • Arabidopsis Proteins*
  • Base Sequence
  • Binding Sites / genetics
  • Cloning, Molecular
  • DNA, Complementary / genetics
  • DNA, Plant / genetics
  • DNA, Plant / metabolism
  • Genes, Homeobox*
  • Genes, Plant*
  • Homeodomain Proteins / genetics
  • Leucine Zippers / genetics
  • Molecular Sequence Data
  • Multigene Family*
  • Plant Proteins / genetics
  • Recombinant Fusion Proteins / genetics
  • Sequence Homology, Amino Acid
  • Transcription Factors / genetics


  • ATHB-8 protein, Arabidopsis
  • Arabidopsis Proteins
  • DNA, Complementary
  • DNA, Plant
  • Homeodomain Proteins
  • PHB protein, Arabidopsis
  • PHV protein, Arabidopsis
  • Plant Proteins
  • Recombinant Fusion Proteins
  • Transcription Factors

Associated data

  • GENBANK/Y10922
  • GENBANK/Y11122