In species with compound leaves, the positions of leaflet primordium initiation are associated with local peaks of auxin accumulation. However, the role of auxin during the late developmental stages and outgrowth of compound leaves remains largely unknown. Using genome resequencing approaches, we identified insertion sites at four alleles of the Linkage analysis and complementation tests showed that the Our work demonstrates that the YUCCA1/YUCCA4 subgroup plays very important roles in the outgrowth of lateral leaflets during compound leaf development of
The formation of developmental boundaries is a common feature of multicellular plants and animals, and impacts the initiation, structure and function of all organs. Maize leaves comprise a proximal sheath that encloses the stem, and a distal photosynthetic blade that projects away from the plant axis. An epidermally derived ligule and a joint‐like auricle develop at the blade/sheath boundary of maize leaves. Mutations disturbing the ligule/auricle region disrupt leaf patterning and impact plant architecture, yet it is unclear how this developmental boundary is established. Targeted microdissection followed by transcriptomic analyses of young leaf primordia were utilized to construct a co‐expression network associated with development of the blade/sheath boundary. Evidence is presented for proximodistal gradients of gene expression that establish a prepatterned transcriptomic boundary in young leaf primordia, before the morphological initiation of the blade/sheath boundary in older leaves. This work presents a conceptual model for spatiotemporal patterning of proximodistal leaf domains, and provides a rich resource of candidate gene interactions for future investigations of the mechanisms of blade/sheath boundary formation in maize.
- Award ID(s):
- 1710973
- NSF-PAR ID:
- 10452953
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- New Phytologist
- Volume:
- 230
- Issue:
- 1
- ISSN:
- 0028-646X
- Page Range / eLocation ID:
- p. 218-227
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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