Morphogenesis depends on the modulation of cell proliferation and differentiation. The reverse genetics approach of García-Cruz et al. reveals that such modulation is dynamically adjusted in response to various signals via a complex transcriptional regulatory network that mediates between such signals and cell-cycle regulation and cell-fate decisions resulting in proliferation, growth or differentiation.
XAL1 (AGL12) is a MADS-box transcription factor and an important component of such networks. This gene participates in root meristem proliferation by regulating cell-cycle components. Interestingly, overexpression of XAL1 is able to affect stem-cell divisions. The study shows that XAL1 is involved in the modulation of cell proliferation to differentiation, transitioning the entrance to the endoreplicative cell cycle during root development.
This paper is part of the Root Biology Special Issue.