title: How to pattern a leaf.
abstract: Leaf development presents a tremendous resource for tackling the question of patterning in biology. Leaves can be simple or highly dissected. They may have elaborated parts such as the tendrils of a pea leaf or the rolled blade of a carnivorous pitcher plant. Despite the variation in size, shape, and function, all leaves initiate in the same manner: from the flanks of a meristem. The maize leaf is useful for analysis of patterning due to the wealth of mutants and the distinct tissues along the proximal distal axis. The blade is distal, the sheath is proximal, and the ligule forms at the blade/sheath boundary. Establishment of this boundary involves the transcription factors LIGULELESS1 and LIGULELESS2 and the kinase LIGULELESS NARROW. The meristem-specific protein KNOTTED1 (KN1) binds and modulates the lg2 gene. Given the localization of KN1 at the proximal end of the leaf from the time of inception, we hypothesize that KN1 has a role in establishing the very proximal end of the leaf, whereas an auxin maximum guides the growing distal tip.
authors.affiliation: Plant Gene Expression Center, USDA-ARS, Albany, California 94710, USA.
authors.forename: N
authors.initials: N
authors.lastname: Bolduc
authors.forename: D
authors.initials: D
authors.lastname: O'Connor
authors.forename: J
authors.initials: J
authors.lastname: Moon
authors.forename: M
authors.initials: M
authors.lastname: Lewis
authors.forename: S
authors.initials: S
authors.lastname: Hake
mesh_terms: D019521:Body Patterning; D007210:Indoleacetic Acids / Q000378:metabolism; D018519:Meristem / Q000378:metabolism; D010641:Phenotype; D018515:Plant Leaves / Q000196:embryology* / Q000378:metabolism; D010940:Plant Proteins / Q000378:metabolism; D003313:Zea mays / Q000196:embryology / Q000378:metabolism
chemical_list: D007210:Indoleacetic Acids; D010940:Plant Proteins