title: Active gene expression of a xyloglucan endotransglucosylase/hydrolase gene, XTH9, in inflorescence apices is related to cell elongation in Arabidopsis thaliana.
abstract: Regulation of cell wall structure plays a central role in growth and differentiation in plants. Xyloglucan endotransglucosylase/hydrolases (XTHs) that catalyze the cleavage and molecular grafting of xyloglucan chains function in loosening and rearrangement of the cell wall. We have characterized XTH9, a member of the XTH family that was isolated by systematic differential screening for highly expressed genes in shoot apices in Arabidopsis. In the vegetative phase, XTH9 transcripts accumulate in the shoot apex region. In the reproductive phase, transcript levels in shoot apices increase further, and they also are detected in flower buds, flower stalks and internodes bearing flowers. XTH9 expression levels were reduced markedly in mutants such as acl which are characterized by short internodal cell lengths, but recover at permissive temperatures in the temperature-sensitive acl mutants. Differential expression of XTH9 along the inflorescence stem was also detected in pin1 where no lateral organs are formed. These observations suggest that XTH9 expression is coordinated with plant development, including the differentiation from vegetative and reproductive meristems and cell elongation of the inflorescence stem.
authors.affiliation: Graduate School of Biological Sciences, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Hyodo
authors.forename: Seiyei
authors.initials: S
authors.lastname: Yamakawa
authors.forename: Yuji
authors.initials: Y
authors.lastname: Takeda
authors.forename: Masao
authors.initials: M
authors.lastname: Tsuduki
authors.forename: Akiho
authors.initials: A
authors.lastname: Yokota
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Nishitani
authors.forename: Takayuki
authors.initials: T
authors.lastname: Kohchi
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000166:cytology / Q000201:enzymology / Q000235:genetics*; D029681:Arabidopsis Proteins / Q000235:genetics; D001483:Base Sequence; D002455:Cell Division / Q000235:genetics; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics; D035264:Flowers / Q000201:enzymology / Q000235:genetics* / Q000254:growth & development; D018507:Gene Expression Regulation, Developmental; D015971:Gene Expression Regulation, Enzymologic; D018506:Gene Expression Regulation, Plant; D016695:Glycosyltransferases / Q000235:genetics*; D017403:In Situ Hybridization; D008969:Molecular Sequence Data; D009154:Mutation; D018749:RNA, Plant / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid
chemical_list: D029681:Arabidopsis Proteins; D018076:DNA, Complementary; D018749:RNA, Plant; D016695:Glycosyltransferases; C473049:xyloglucan - xyloglucosyltransferase