Jan Traas

..How dynamic cellular events are coordinated and how they are linked to the regular patterns of organ initiation is a major issue in plant developmental biology...

..Our results suggest that the levels of SWP, besides their role in pattern formation at the meristem, play an important role in defining the duration of cell proliferation...

..In this case, cell growth and, later, cell differentiation were inhibited, suggesting an important role for DNA synthesis in growth and patterning...

..In particular, cytokinins and auxins are implicated in the maintenance of meristem identity and phyllotaxis, respectively...

..We therefore suggest that the phyllotactic pattern in a fully grown stem results not only from the organogenetic activity of the meristem, but also from the subsequent growth pattern during stem development...

..It is likely that combining mechanical signals and biochemical gradients could confer more robustness to plant development...

..KNAT2, although the closest related member of the family to KNAT6, did not have such a function...

..In this review, we use shoot apical meristem development to illustrate how biochemistry and biomechanics cooperate to integrate the local cellular gene input into global growth patterns...

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..We relate this enlargement to the division patterns of the boundary cells. We propose that miR164 constrains the expansion of the boundary domain, by degrading CUC1 and CUC2 mRNAs...

..Our results illustrate the value of developing response input sensors such as DII-VENUS to provide high-resolution spatio-temporal information about hormone distribution and response during plant growth and development...

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..Our results provide evidence that the auxin signalling network is essential to create robust patterns at the shoot apex...

..The first models have begun to reproduce gene network behaviours and dynamical shape changes, providing new insight in the control of morphogenesis...

..In this review, we will discuss these issues focusing on the shoot apical meristem, a population of stem cells that is responsible for the initiation of the aerial organs of the plant...

..To unravel this intricate signaling network at the SAM, systems biology approaches, involving not only molecular genetics but also live imaging and computational modeling, have become increasingly important...

..We also observed floral phenotypes not observed in loss-of-function or constitutive gain-of-function backgrounds, revealing additional roles of UFO in outgrowth of petal primordia...

..The protocol uses serial optical sections made with the confocal microscope. It includes specially designed algorithms to automate the identification of cell lineage and to analyse the quantitative behaviour of the meristem surface...

..These data suggest that ethylene and cytokinins act antagonistically in the meristem via KNAT2 to regulate the meristem activity...

..Cell proliferation depends on nutrient distribution but, in turn, the use of the same nutrients depends on the activity of cell cycle regulators such as E2F transcription factors...

..Our results suggest a model where PIN1 and MP regulate apical patterning partially through the control of CUC gene expression...

..In particular, they suggest an important role for the meristem summit in the distribution of auxin. We confirm these predictions by further experimentation and propose a detailed model for the dynamics of auxin fluxes at the shoot apex...

..We conclude that BIF2 is important for PIN organization and could play a role in the establishment of polar auxin fluxes in maize inflorescence, indirectly modulating the process of axillary meristem formation and development...

..Auxin accumulation occurs only at certain minimal distances from existing primordia, defining the position of future primordia. This model for phyllotaxis accounts for its reiterative nature, as well as its regularity and stability...

..We also show that this strategy can be applied to mis-express genes with developmental roles, by manipulating expression of the SHOOT MERISTEMLESS (STM) and CYCLIN D3;1 (CYCD3;1) genes during plant development...

..These features suggest a key role for MGO3 in meristematic cell divisions and would be of interest for the comparison between plant and animal development...

..Our data indicate that the Elongator complex is evolutionarily conserved in structure and function but reveal that the mechanism by which it stimulates cell proliferation is different in yeast and plants...

..Therefore, these results suggest that TEL is not only associated with leaf initiation but more generally with cell differentiation in Poaceae...

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