Nuclear trapping by GL3 controls intercellular transport and redistribution of TTG1 protein in Arabidopsis.
Trichome patterning on Arabidopsis leaves is one of the best-studied model systems for two-dimensional de novo patterning. In addition to an activator-inhibitor-related mechanism, we previously proposed a depletion mechanism to operate during this process such that GLABRA3 (GL3) traps the trichome-promoting factor TRANSPARENT TESTA GLABRA1 (TTG1) in trichomes that, in turn, results in a depletion of TTG1 in trichome neighbouring cells. In this manuscript we analyze the molecular basis underlying this trapping mechanism. We demonstrate the ability of GL3 to regulate TTG1 mobility by expressing TTG1 and GL3 in different tissue layers in different combinations. We further show that TTG1 trapping by GL3 is based on direct interaction between both proteins and recruitment in the nucleus.
University of Cologne, Botanical Institute III, Zülpicher Strasse 47b, 50674 Köln, Germany.
Rachappa
R
Balkunde
Daniel
D
Bouyer
Martin
M
Hülskamp
D021581:Active Transport, Cell Nucleus / Q000235:genetics / Q000502:physiology; D017360:Arabidopsis / Q000166:cytology / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism* / Q000502:physiology*; D051792:Basic Helix-Loop-Helix Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D002467:Cell Nucleus / Q000235:genetics / Q000378:metabolism*; D030821:Plants, Genetically Modified; D011485:Protein Binding / Q000235:genetics / Q000502:physiology; D021381:Protein Transport / Q000235:genetics; D014018:Tissue Distribution / Q000235:genetics; D014162:Transfection
D029681:Arabidopsis Proteins; D051792:Basic Helix-Loop-Helix Proteins; C417284:GL3 protein, Arabidopsis; C121067:TTG1 protein, Arabidopsis