Quantification of growth at the shoot apical meristem of Arabidopsis
نویسندگان
چکیده
In the process of morphogenesis primordia of lateral organs, like leaves or flowers, are formed at the shoot apical meristem (SAM). In order to maintain the ability to organ formation, the SAM itself has to be self-perpetuated, i.e. its general shape and size have to be maintained, despite the fact that portions of SAM periphery are continuously used up for lateral organ formation. Thus growth at the SAM comprises two components: the self-perpetuation and the formation of lateral organ primordia. The interior of SAM is divided into two zones, which participate in different growth components. Cells of the central zone, which includes putative stem cells, contribute mainly to the selfperpetuation. Cells of the peripheral zone participate in the formation of lateral organ primordia. In principle, these two zones are geometrically defined. The significance of this zonation is confirmed by expression patterns of genes regulating SAM functioning and maintenance. However, how the zonation and gene expression patterns are related to the distribution of growth at the SAM remains an open question. Theoretically both the self-perpetuation of the SAM and the primordium formation could be realised in various ways, i.e. with various growth distributions. Therefore a precise quantification of growth at the SAM is a crucial step to understand shoot morphogenesis.
منابع مشابه
QUANTITATIVE AND QUALITATIVE CHANGES IN SHOOT APICAL MERISTEM OF SAFFRON CROCUS DURING THE PERIOD OF GROWTH AND DEVELOPMENT
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