抄録
BBR/BPC proteins comprise a class of transcription factors that are confined to the plant kingdom. They have been identified due to their specific binding to a conserved simple di-nucleotide sequence repeat DNA-element (GA/TC)n.
Three distinct domain structures could be identified common to most BBR/BPC proteins: A N-terminal putative activation/interaction domain, a nuclear localization sequence (NLS) and a highly conserved basic DNA-binding domain, which is structured as a typical zinc-finger-like motif at its C-terminus.
Based on their differing N-terminal domains, the BBR/BPC family can be subdivided into distinct groups. Phylogenetic analysis on the DNA-binding domain sequence strongly supports this division.
BBR/BPC proteins exhibit group-wise expression patterns that are indicative of a high degree of functional redundancy between the group members.
Group II proteins form homo-/hetero-oligomeric structures in the nucleus and the nucleolus, which are mediated by a novel type of coiled coil-interaction domain. Target site analyses of putative binding motifs suggest a role for BBR/BPC proteins in regulating other transcription factor or hormone signalling related genes.
