The ANGUSTIFOLIA gene of Arabidopsis, a plant CtBP gene, regulates leaf-cell expansion, the arrangement of cortical microtubules in leaf cells and expression of a gene involved in cell-wall formation.
We previously showed that the ANGUSTIFOLIA (AN) gene regulates the width of leaves of Arabidopsis thaliana, by controlling the polar elongation of leaf cells. In the present study, we found that the abnormal arrangement of cortical microtubules (MTs) in an leaf cells appeared to account entirely for the abnormal shape of the cells. It suggested that the AN gene might regulate the polarity of cell growth by controlling the arrangement of cortical MTs. We cloned the AN gene using a map-based strategy and identified it as the first member of the CtBP family to be found in plants. Wild-type AN cDNA reversed the narrow-leaved phenotype and the abnormal arrangement of cortical MTs of the an-1 mutation. In the animal kingdom, CtBPs self-associate and act as co-repressors of transcription. The AN protein can also self-associate in the yeast two-hybrid system. Furthermore, microarray analysis suggested that the AN gene might regulate the expression of certain genes, e.g. the gene involved in formation of cell walls, MERI5. A discussion of the molecular mechanisms involved in the leaf shape regulation is presented based on our observations.
Kim
Gyung-Tae
GT
National Institute for Basic Biology/Center for Integrative Bioscience, 38 Nishigounaka, Myodaiji-cho, Okazaki 444-8585, Japan.
Shoda
Keiko
K
Tsuge
Tomohiko
T
Cho
Kiu-Hyung
KH
Uchimiya
Hirofumi
H
Yokoyama
Ryusuke
R
Nishitani
Kazuhiko
K
Tsukaya
Hirokazu
H
D000429:Alcohol Oxidoreductases; D000595:Amino Acid Sequence; D000818:Animals; D017360:Arabidopsis; D029681:Arabidopsis Proteins / Q000145:classification / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D048429:Cell Size; D002473:Cell Wall; D003001:Cloning, Molecular; D004268:DNA-Binding Proteins / Q000145:classification / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D015870:Gene Expression; D020869:Gene Expression Profiling; D017343:Genes, Plant / Q000502:physiology*; D016695:Glycosyltransferases; D018519:Meristem; D051379:Mice; D008870:Microtubules; D008969:Molecular Sequence Data; D016296:Mutagenesis; D010750:Phosphoproteins / Q000145:classification; D018515:Plant Leaves / Q000166:cytology; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D012097:Repressor Proteins / Q000145:classification / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D012441:Saccharomyces cerevisiae; D017386:Sequence Homology, Amino Acid
D000429:Alcohol Oxidoreductases; D029681:Arabidopsis Proteins; D004268:DNA-Binding Proteins; D016695:Glycosyltransferases; D010750:Phosphoproteins; D010940:Plant Proteins; D012097:Repressor Proteins; C452846:DETORQEO protein, Arabidopsis; C096794:C-terminal binding protein; C000627068:XTH24 protein, Arabidopsis