Role of a positive regulator of root hair development, CAPRICE, in Arabidopsis root epidermal cell differentiation

• Published in: Development (Cambridge) Vol. 129; no. 23; pp. 5409 - 5419
• Main Authors: Wada, Takuji, Kurata, Tetsuya, Tominaga, Rumi, Koshino-Kimura, Yoshihiro, Tachibana, Tatsuhiko, Goto, Koji, Marks, M David, Shimura, Yoshiro, Okada, Kiyotaka
• Format: Journal Article
• Language: English
• Published: England The Company of Biologists Limited 01.12.2002
• Subjects: Arabidopsis - cytology; Arabidopsis - genetics; Arabidopsis - physiology; Arabidopsis Proteins - metabolism; Cell Differentiation - physiology; Gene Expression Regulation, Plant; Genes, Plant; Genes, Reporter; Homeodomain Proteins - metabolism; In Situ Hybridization; Phenotype; Plant Epidermis - cytology; Plant Epidermis - physiology; Plant Proteins - metabolism; Plant Roots - cytology; Plant Roots - growth & development; Plants, Genetically Modified; Promoter Regions, Genetic; Protein Binding; Proto-Oncogene Proteins c-myb - metabolism; Recombinant Fusion Proteins - genetics; Recombinant Fusion Proteins - metabolism; Two-Hybrid System Techniques
• ISSN: 0950-1991; 1477-9129
• DOI: 10.1242/dev.00111

In Arabidopsis , root hairs are formed only from a set of epidermal cells named trichoblasts or hair-forming cells. Previous studies showed CAPRICE ( CPC ) promotes differentiation of hair-forming cells by controlling a negative regulator, GLABRA2 ( GL2 ), which is preferentially expressed in hairless cells. Here, we show that CPC is also predominantly expressed in the hairless cells, but not in the neighboring hair-forming cells, and that CPC protein moves to the hair-forming cells and represses the GL2 expression. We also show that the N terminus of bHLH protein interacts with CPC and is responsible for the GL2 expression. We propose a model in which CPC plays a key role in the fate-determination of hair-forming cells.