title: Axillary meristem development in the branchless Zu-0 ecotype of Arabidopsis thaliana.
abstract: Axillary meristems form in the leaf axils during post-embryonic development. In order to initiate the genetic dissection of axillary meristem development, we have characterized the late-flowering branchless ecotype of Arabidopsis thaliana (L.) Heynh., Zu-0. The first-formed rosette leaves of Zu-0 plants all initiate axillary meristems, but later-formed leaves of the rosette remain branchless. Alteration in the meristem development is axillary meristem-specific because the shoot apical and floral meristems develop normally. Scanning electron microscopy, histology and RNA in situ analysis with SHOOTMERISTEMLESS ( STM), a marker for meristematic tissues, show that a mound of cells form and STM mRNA accumulates in barren leaf axils, indicating that axillary meristems initiate but arrest in their development prior to organizing a meristem proper. Expression and retention of the STM RNA in barren leaf axils further suggests that STM expression is not sufficient for the establishment of the axillary meristem proper.
authors.affiliation: Department of Plant Sciences, University of Western Ontario, London, Canada.
authors.forename: Anna
authors.initials: A
authors.lastname: Kalinina
authors.forename: Nela
authors.initials: N
authors.lastname: Mihajlović
authors.forename: Vojislava
authors.initials: V
authors.lastname: Grbić
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development*; D029681:Arabidopsis Proteins; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D005819:Genetic Markers; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism; D017403:In Situ Hybridization; D018519:Meristem / Q000254:growth & development* / Q000648:ultrastructure; D008855:Microscopy, Electron, Scanning; D009154:Mutation; D010641:Phenotype; D018515:Plant Leaves / Q000254:growth & development*; D018547:Plant Stems / Q000254:growth & development*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D005819:Genetic Markers; D018398:Homeodomain Proteins; D012333:RNA, Messenger; C097496:STM protein, Arabidopsis