Abstract
Arabidopsis leaf trichomes provide an excellent model system to study cell differentiation. Using a collection of Arabidopsis full-length cDNA over-expression (FOX) lines, we identified a transgenic FOX line that develops remarkably large leaf trichomes compared wild-type. Our sequencing analysis revealed that the corresponding gene, which we named WIND FARM, encodes a putative transcription factor that has not been previously characterised. Furthermore, the sequence alignment illustrated that the cDNA clone is strongly truncated, possibly leading to a dominant negative phenotype. In concert with this, three different T-DNA insertion lines display giant trichome phenotypes indistinguishable from FOX mutants, suggesting that WF acts as a negative regulator of trichome cell growth. Additional genetic studies show that WF acts downstream of trichome patterning and differentiation, confirming its exclusive role in cell expansion.
