Dual functions of the KNOTTED1 homeodomain: sequence-specific DNA binding and regulation of cell-to-cell transport.
Homeodomain proteins are well-characterized developmental regulators that control expression of target genes through sequence-specific DNA binding. The homeodomain forms a trihelical structure, with the third helix conferring specific interactions with the DNA major groove. A specific class of plant homeodomain proteins, called KNOX [KNOTTED1 (KN1)-like homeobox], also has the ability to signal between cells by directly trafficking through intercellular channels called plasmodesmata. Trafficking is mediated by a signal that is also contained within the homeodomain. Movement protein binding protein 2C was identified as a protein that interacts with the KN1 homeodomain and regulates the cell-to-cell trafficking of KN1 by sequestering the protein on microtubules. Therefore, KN1 has multiple potential cellular addresses, each of which is conferred by its homeodomain.
Bolduc
Nathalie
N
Plant Gene Expression Center, 800 Buchanan Street, Albany, CA 94710, USA.
Hake
Sarah
S
Jackson
David
D
D002450:Cell Communication; D018744:DNA, Plant / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000378:metabolism; D018398:Homeodomain Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D009154:Mutation; D010940:Plant Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction; D011198:Solanum tuberosum / Q000201:enzymology; D014026:Nicotiana / Q000201:enzymology; D014158:Transcription, Genetic
D018744:DNA, Plant; D004268:DNA-Binding Proteins; D018398:Homeodomain Proteins; C095848:Kn1 protein, plant; D010940:Plant Proteins