Plant Molecular Biology

, Volume 38, Issue 4, pp 609–622

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

  • Giovanna Sessa
  • Corinna Steindler
  • Giorgio Morelli
  • Ida Ruberti
Article

DOI: 10.1023/A:1006016319613

Cite this article as:
Sessa, G., Steindler, C., Morelli, G. et al. Plant Mol Biol (1998) 38: 609. doi:10.1023/A:1006016319613

Abstract

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.

binding site selectiongene expressionhomeobox-leucine zipper genesprotein-DNA interaction

Copyright information

© Kluwer Academic Publishers 1998

Authors and Affiliations

  • Giovanna Sessa
    • 1
  • Corinna Steindler
    • 1
  • Giorgio Morelli
    • 2
  • Ida Ruberti
    • 1
  1. 1.Centro di studio per gli Acidi Nucleici, c/o Dipartimento di Genetica e Biologia MolecolareUniversità di Roma La SapienzaRomeItaly.
  2. 2.Unità di Nutrizione SperimentaleIstituto Nazionale della NutrizioneRomeItaly;