Abstract
The primary root of Arabidopsis thaliana has a highly organized radial cell pattern. Root cells are organized as concentric rings consist of lateral root cap, epidermis, ground tissue (endodermis and cortex), and pericycle surrounding the central stele.
A few mutants defective in the root radial pattern have been isolated. In scarecrow (scr) and short-root (shr) mutants, the cortex/endodermis stem cell produces only a single cell layer in the ground tissue. Both SHR and SCR encode GRAS-type transcription factors and function in the ground tissue development.
To reveal novel regulatory mechanisms underlying radial cell patterning, we isolated several Arabidopsis mutants defective in the root cell patterns. In one of the mutants (5gf32), an extra layer was produced in ground tissue and their cells were not arranged concentrically. We characterized the cell patterning in 5gf32 mutant by using differentiation marker expressions and will discuss possible genetic interaction between 5GF32 and SHR/SCR pathways.
