Establishment of polarity in angiosperm lateral organs.
In seed plants, lateral organs such as leaves and floral organs are formed from the flanks of apical meristems. Therefore, they have an inherent positional relationship: organ primordia have an adaxial side next to the meristem, and an abaxial one away from the meristem. Surgical and genetic studies suggest that a morphogenetic gradient, which originates in the meristem, converts the inherent polarity into a functional one. Once an adaxial-abaxial axis of polarity is established within organ primordia, it provides cues for proper lamina growth and asymmetrical development. Several key participants in this process have been identified, and analyses of these genes support and refine our views of axis formation in plants. The complex relationships between and within various members of these plant-specific gene families (class III HD-ZIPs, YABBYs and KANADIs) might account for a substantial part of the morphological variation in lateral organs of seed plants.
Bowman
John L
JL
Section of Plant Biology, University of California Davis, Davis, CA 95616, USA. jlbowman@ucdavis.edu
Eshed
Yuval
Y
Baum
Stuart F
SF
D029681:Arabidopsis Proteins; D019521:Body Patterning / Q000235:genetics*; D017343:Genes, Plant / Q000235:genetics*; D018398:Homeodomain Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D019684:Magnoliopsida / Q000254:growth & development* / Q000648:ultrastructure; D009024:Morphogenesis; D009154:Mutation; D010641:Phenotype; D010802:Phylogeny; D010940:Plant Proteins; D018514:Plant Structures / Q000254:growth & development* / Q000648:ultrastructure; D015398:Signal Transduction / Q000502:physiology; D014157:Transcription Factors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
D029681:Arabidopsis Proteins; D018398:Homeodomain Proteins; C430846:KANADI protein, Arabidopsis; D010940:Plant Proteins; D014157:Transcription Factors; C121841:YABBY2 protein, Arabidopsis; C121842:YABBY3 protein, Arabidopsis