LMI1 homeodomain protein regulates organ proportions by spatial modulation of endoreduplication

• Published in: Genes & development Vol. 32; no. 21-22; pp. 1361 - 1366
• Main Authors: Vuolo, Francesco, Kierzkowski, Daniel, Runions, Adam, Hajheidari, Mohsen, Mentink, Remco A., Gupta, Mainak Das, Zhang, Zhongjuan, Vlad, Daniela, Wang, Yi, Pecinka, Ales, Gan, Xiangchao, Hay, Angela, Huijser, Peter, Tsiantis, Miltos
• Format: Journal Article
• Language: English
• Published: United States Cold Spring Harbor Laboratory Press 01.11.2018
• Subjects: Arabidopsis - anatomy & histology; Arabidopsis - genetics; Arabidopsis - growth & development; Arabidopsis - metabolism; Arabidopsis Proteins - genetics; Arabidopsis Proteins - metabolism; Arabidopsis Proteins - physiology; Endoreduplication; Homeodomain Proteins - genetics; Homeodomain Proteins - metabolism; Homeodomain Proteins - physiology; Plant Leaves - anatomy & histology; Plant Leaves - growth & development; Plant Leaves - metabolism; Plant Leaves - ultrastructure; Protein-Serine-Threonine Kinases - metabolism; Research Communication; Transcription Factors - genetics; Transcription Factors - metabolism; Transcription Factors - physiology; live imaging; plant homeobox; organ proportions; leaf development
• ISSN: 0890-9369; 1549-5477; 1549-5477
• DOI: 10.1101/gad.318212.118

How the interplay between cell- and tissue-level processes produces correctly proportioned organs is a key problem in biology. In plants, the relative size of leaves compared with their lateral appendages, called stipules, varies tremendously throughout development and evolution, yet relevant mechanisms remain unknown. Here we use genetics, live imaging, and modeling to show that in Arabidopsis leaves , the LATE MERISTEM IDENTITY1 (LMI1) homeodomain protein regulates stipule proportions via an endoreduplication-dependent trade-off that limits tissue size despite increasing cell growth. LM1 acts through directly activating the conserved mitosis blocker WEE1 , which is sufficient to bypass the LMI1 requirement for leaf proportionality.