Article

Cell cycle regulates cell type in the Arabidopsis sepal

Development (Impact Factor: 6.27). 10/2012; 139(23). DOI: 10.1242/dev.082925
Source: PubMed

ABSTRACT The formation of cellular patterns during development requires the coordination of cell division with cell identity specification. This coordination is essential in patterning the highly elongated giant cells, which are interspersed between small cells, in the outer epidermis of the Arabidopsis thaliana sepal. Giant cells undergo endocycles, replicating their DNA without dividing, whereas small cells divide mitotically. We show that distinct enhancers are expressed in giant cells and small cells, indicating that these cell types have different identities as well as different sizes. We find that members of the epidermal specification pathway, DEFECTIVE KERNEL1 (DEK1), MERISTEM LAYER1 (ATML1), Arabidopsis CRINKLY4 (ACR4) and HOMEODOMAIN GLABROUS11 (HDG11), control the identity of giant cells. Giant cell identity is established upstream of cell cycle regulation. Conversely, endoreduplication represses small cell identity. These results show not only that cell type affects cell cycle regulation, but also that changes in the cell cycle can regulate cell type.

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    • "Apoplastic signalling mediated by ACR4, like DEK1 function, is necessary for the maintenance of HD-ZIP IV gene expression (San-Bento et al., 2014). However, genetic analysis carried out in Arabidopsis and maize (Becraft et al., 2002; Roeder et al., 2012) suggests that DEK1 and ACR4 act in parallel. "
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    Development 05/2015; DOI:10.1242/dev.122325 · 6.27 Impact Factor
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    • "RESEARCH ARTICLE Development (2015) 142, 1-11 doi:10.1242/dev.117168 DEVELOPMENT (Roeder et al., 2012). The HDG1-mediated increase in cell ploidy in leaves might be a secondary consequence of the increase in margin cells. "
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