Bencivenga S, Serrano-Mislata A, Bush M, Fox S, Sablowski R. Control of Oriented Tissue Growth through Repression of Organ Boundary Genes Promotes Stem Morphogenesis.
Dev Cell 2016;
39:198-208. [PMID:
27666746 PMCID:
PMC5084710 DOI:
10.1016/j.devcel.2016.08.013]
[Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Revised: 04/14/2016] [Accepted: 08/24/2016] [Indexed: 12/16/2022]
Abstract
The origin of the stem is a major but poorly understood aspect of plant development, partly because the stem initiates in a relatively inaccessible region of the shoot apical meristem called the rib zone (RZ). We developed quantitative 3D image analysis and clonal analysis tools, which revealed that the Arabidopsis homeodomain protein REPLUMLESS (RPL) establishes distinct patterns of oriented cell division and growth in the central and peripheral regions of the RZ. A genome-wide screen for target genes connected RPL directly to many of the key shoot development pathways, including the development of organ boundaries; accordingly, mutation of the organ boundary gene LIGHT-SENSITIVE HYPOCOTYL 4 restored RZ function and stem growth in the rpl mutant. Our work opens the way to study a developmental process of importance to crop improvement and highlights how apparently simple changes in 3D organ growth can reflect more complex internal changes in oriented cell activities.
Image and sector analysis revealed 3D growth patterns in early stem development
Arabidopsis RPL controls oriented cell division and growth in the rib meristem
RPL interacts with many of the key genes that regulate shoot organogenesis
RPL controls oriented growth by directly repressing organ boundary genes
Collapse