Abstract
ANGUSTIFOLIA (AN) is a plant homologue of animal CtBP (transcription corepressor)/ BARS (a protein involved in Golgi maintenance) and thought to control polar cell expansion in the leaf-width direction. Although AN has been expected to function as CtBP, the molecular function of AN is not yet elucidated. In this study, swapping experiment was carried out between the AN gene and Drosophila melanogaster dCtBP. As a result, it appeared that AN did not function as CtBP in drosophila. In addition, analysis of intracellular-localization-site-directed mutagenesis of AN suggested that the function of AN differs from that of CtBP. The observation of the intracellular localization revealed that AN localizes in novel dot-like structures closely associated with the Golgi apparatus. This localization is also unexpected from the hypothesis that AN might be a plant BARS. Further analysis is in place to uncover the relationship between such particular localization and the polar cell expansion.
