title: HANABA TARANU is a GATA transcription factor that regulates shoot apical meristem and flower development in Arabidopsis.
abstract: We have isolated a new mutant, hanaba taranu (han), which affects both flower and shoot apical meristem (SAM) development in Arabidopsis thaliana. Mutants have fused sepals and reduced organ numbers in all four whorls, especially in the 2nd (petal) and 3rd (stamen) whorls. han meristems can become flatter or smaller than in the wild type. HAN encodes a GATA-3-like transcription factor with a single zinc finger domain. HAN is transcribed at the boundaries between the meristem and its newly initiated organ primordia and at the boundaries between different floral whorls. It is also expressed in vascular tissues, developing ovules and stamens, and in the embryo. han interacts strongly with clavata (clv) mutations (clv1, clv2, and clv3), resulting in highly fasciated SAMs, and we find that WUS expression is altered in han mutants from early embryogenesis. In addition, HAN is ectopically expressed both in clv1 and clv3 mutants. We propose that HAN is normally required for establishing organ boundaries in shoots and flowers and for controlling the number and position of WUS-expressing cells. Ectopic HAN expression causes growth retardation, aberrant cell division patterns, and loss of meristem activity, suggesting that HAN is involved in controlling cell proliferation and differentiation.
authors.affiliation: Division of Biology, California Institute of Technology, Pasadena, California 91125, USA. zhaoyx@caltech.edu <zhaoyx@caltech.edu>
authors.forename: Yuanxiang
authors.initials: Y
authors.lastname: Zhao
authors.forename: Leonard
authors.initials: L
authors.lastname: Medrano
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Ohashi
authors.forename: Jennifer C
authors.initials: JC
authors.lastname: Fletcher
authors.forename: Hao
authors.initials: H
authors.lastname: Yu
authors.forename: Hajime
authors.initials: H
authors.lastname: Sakai
authors.forename: Elliot M
authors.initials: EM
authors.lastname: Meyerowitz
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000254:growth & development* / Q000648:ultrastructure; D029681:Arabidopsis Proteins / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D003001:Cloning, Molecular; D050980:GATA Transcription Factors; D017403:In Situ Hybridization; D018519:Meristem / Q000254:growth & development*; D008969:Molecular Sequence Data; D010641:Phenotype; D014157:Transcription Factors / Q000737:chemistry / Q000235:genetics / Q000502:physiology*
chemical_list: D029681:Arabidopsis Proteins; D050980:GATA Transcription Factors; C497900:HANABA TARANU protein, Arabidopsis; D014157:Transcription Factors