A novel cell-to-cell trafficking assay indicates that the KNOX homeodomain is necessary and sufficient for intercellular protein and mRNA trafficking.
Cell-to-cell trafficking of regulatory proteins is a novel mechanism for communication during cell fate specification in plants. Although several developmental proteins traffic cell-to-cell, no signals that are both necessary and sufficient for this function in developmental proteins have been described. We developed a novel trafficking assay using trichome rescue in Arabidopsis. Fusion to KNOTTED1 (KN1) conferred gain-of-trafficking function to the cell-autonomous GLABROUS1 (GL1) protein. We show that the KNOX homeodomain (HD) is necessary and sufficient for intercellular trafficking, identifying a novel function for the HD as the minimal sequence required for trafficking of KN1 and its associated mRNA.
Kim
Jae-Yean
JY
Division of Applied Life Science (BK21 program), Environmental Biotechnology National Core Research Center, PMBBRC, Gyeongsang National University, Jinju 660-701, Korea. kimjy@nongae.gsnu.ac.kr
Rim
Yeonggil
Y
Wang
Jing
J
Jackson
David
D
D017360:Arabidopsis / Q000378:metabolism*; D018398:Homeodomain Proteins / Q000378:metabolism*; D010940:Plant Proteins / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D021381:Protein Transport / Q000502:physiology; D012333:RNA, Messenger / Q000378:metabolism*; D015398:Signal Transduction / Q000502:physiology
D018398:Homeodomain Proteins; C095848:Kn1 protein, plant; D010940:Plant Proteins; D012333:RNA, Messenger