Cytokinin regulates compound leaf development in tomato.
Leaf shape diversity relies on transient morphogenetic activity in leaf margins. However, how this morphogenetic capacity is maintained is still poorly understood. Here, we uncover a role for the hormone cytokinin (CK) in the regulation of morphogenetic activity of compound leaves in tomato (Solanum lycopersicum). Manipulation of CK levels led to alterations in leaf complexity and revealed a unique potential for prolonged growth and morphogenesis in tomato leaves. We further demonstrate that the effect of CK on leaf complexity depends on proper localization of auxin signaling. Genetic analysis showed that reduction of CK levels suppresses the effect of Knotted1 like homeobox (KNOXI) proteins on leaf shape and that CK can substitute for KNOXI activity at the leaf margin, suggesting that CK mediates the activity of KNOXI proteins in the regulation of leaf shape. These results imply that CK regulates flexible leaf patterning by dynamic interaction with additional hormones and transcription factors.
The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, Hebrew University, Rehovot, Israel.
Eilon
E
Shani
Hadas
H
Ben-Gera
Sharona
S
Shleizer-Burko
Yogev
Y
Burko
David
D
Weiss
Naomi
N
Ori
D003583:Cytokinins / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism; D007210:Indoleacetic Acids / Q000378:metabolism; D018551:Solanum lycopersicum / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D018515:Plant Leaves / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D018749:RNA, Plant / Q000235:genetics
D003583:Cytokinins; D018398:Homeodomain Proteins; D007210:Indoleacetic Acids; C405985:Knox1 protein, plant; D010940:Plant Proteins; D018749:RNA, Plant