Ankyrin repeats are present in a great variety of proteins of eukaryotes, prokaryotes and some viruses and they function as protein-protein interaction domains. The BTB/POZ domain is an evolutionarily conserved protein-protein interaction domain that is found at the N terminus of some C2H2-type zinc finger transcription factors and in actin binding proteins. Examples of the BTB/POZ domain have been identified in organisms from yeast to human. The BTB (for Broad Complex, tramtrack and bric a brac) / POZ (for poxviruses and zinc finger) are an approximately 20-amino acid conserved and hydrophobic domain. These two domains are present in a many plant proteins. One of the classical examples is BLADE-ON-PETIOLE1 of Arabidopsis.
1. Albagli, O., Dhordain, P., Deweindt, C., Lecocq, G., and Leprince, D. (1995). The BTB/POZ domain: a new protein-protein interaction motif common to DNA- and actin-binding proteins.
2. C. M. Ha, J. H. Jun, H. G. Nam, J. C. Fletcher, BLADE-ON-PETIOLE1 encodes a BTB/POZ domain protein required for leaf morphogenesis in Arabidopsis thaliana. Plant Cell Physiol 45, 1361 (2004)