Abstract
CAPRICE (CPC) encodes a small protein with R3 MYB motif and promotes root-hair cell differentiation in Arabidopsis. Analysis of pCPC::CPC:GFP revealed that the CPC protein moves from hairless cells to root-hair cells. Two motifs, one in the N-terminal region and the other in the Myb domain, are required for cell-to-cell movement. When CPC was expressed ectopically using cell type-specific promoters, CPC was found to move from the root-hair cells to hairless cells, but not from the stele to the epidermis. We also examined the movement ability of products of CPC-homologous genes.
One of bHLH gene, GLABRA3 (GL3), was strongly expressed in root-hair cell files. However, gl3 had increased numbers of root hair. Combined with the analysis of pGL3::GL3:GFP, we concluded that GL3 also might move from hair-cell to hairless cell.
A summary of the cell-to-cell movement of regulatory factors for epidermis differentiation will be presented.
