PLATZ Transcription Factor Family
Complementary DNA encoding a DNA-binding protein, designated PLATZ1 (plant AT-rich
sequence- and zinc-binding protein 1), was isolated from peas. The amino acid sequence
of the protein is similar to those of other uncharacterized proteins predicted from the
genome sequences of higher plants. However, no paralogous sequences have been found
outside the plant kingdom. Multiple alignments among these paralogous proteins show
that several cysteine and histidine residues are invariant, suggesting that these
proteins are a novel class of zinc-dependent DNA-binding proteins with two distantly
located regions, C-x(2)-H-x(11)-C-x(2)-C-x((4-5))-C-x(2)-C-x((3-7))-H-x(2)-H and
C-x(2)-C-x((10-11))-C-x(3)-C. In an electrophoretic mobility shift assay, the zinc
chelator 1,10-o-phenanthroline inhibited DNA binding, and two distant zinc-binding
regions were required for DNA binding. A protein blot with (65)ZnCl(2) showed that both
regions are required for zinc-binding activity. The PLATZ1 protein non-specifically
binds to A/T-rich sequences, including the upstream region of the pea GTPase pra2 and
plastocyanin petE genes. Expression of the PLATZ1 repressed those of the reporter
constructs containing the coding sequence of luciferase gene driven by the cauliflower
mosaic virus (CaMV) 35S90 promoter fused to the tandem repeat of the A/T-rich
sequences. These results indicate that PLATZ1 is a novel class of plant-specific
zinc-dependent DNA-binding protein responsible for A/T-rich sequence-mediated
transcriptional repression.
40 predicted putative PLATZ TF peptide,
CDS, and cDNA sequences;
blast HSP, and multiple sequence alignment in
Soy - TFKB.
40 PLATZ domain peptide sequences with
alignment and phylogeny tree.
28 PLATZ protein and DNAsequences with
annotations for soybean in PlantTFDB. Most are partial sequences.
Last updated by Dr. Jeff Chen on June 4, 2009.
