摘要
In Arabidopsis,once seeds germinate,a group of cells constituting the stem cell niche at the root apex become activated and undergo division and differentiation to form root meristem and three different zones of root tissues,i.e.,the division,elongation,and differentiation zones(Figure 1).The positioning of the so-called transition zone(TZ)between the division and elongation zone involves a complex regulatory network governed by auxin and cytokinin signaling,both of which safeguard the correct patterning of root zonation.
