title: Partitioning the apical domain of the Arabidopsis embryo requires the BOBBER1 NudC domain protein.
abstract: The apical domain of the embryo is partitioned into distinct regions that will give rise to the cotyledons and the shoot apical meristem. In this article, we describe a novel screen to identify Arabidopsis thaliana embryo arrest mutants that are defective in this partitioning, and we describe the phenotype of one such mutant, bobber1. bobber1 mutants arrest at the globular stage of development, they express the meristem-specific SHOOTMERISTEMLESS gene throughout the top half of the embryo, and they fail to express the AINTEGUMENTA transcript normally found in cotyledons. Thus, BOBBER1 is required to limit the extent of the meristem domain and/or to promote the development of the cotyledon domains. Based on expression of early markers for apical development, bobber1 mutants differentiate protodermis and undergo normal early apical development. Consistent with a role for auxin in cotyledon development, BOBBER1 mutants fail to express localized maxima of the DR5:green fluorescent protein reporter. BOBBER1 encodes a protein with homology to the Aspergillus nidulans protein NUDC that has similarity to protein chaperones, indicating a possible role for BOBBER1 in synthesis or transport of proteins involved in patterning the Arabidopsis embryo.
authors: Department of Genetics, University of Wisconsin, Madison, Wisconsin 53706, USA.
authors: Rebecca Joy
authors: RJ
authors: Jurkuta
authors: Nicholas J
authors: NJ
authors: Kaplinsky
authors: Jennifer E
authors: JE
authors: Spindel
authors: M Kathryn
authors: MK
authors: Barton
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000196:embryology* / Q000235:genetics; D029681:Arabidopsis Proteins / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D005656:Fungal Proteins / Q000737:chemistry / Q000235:genetics; D018506:Gene Expression Regulation, Plant / Q000235:genetics / Q000502:physiology; D017403:In Situ Hybridization; D018613:Microscopy, Confocal; D008969:Molecular Sequence Data; D030821:Plants, Genetically Modified / Q000196:embryology / Q000235:genetics; D017434:Protein Structure, Tertiary / Q000235:genetics / Q000502:physiology; D012639:Seeds / Q000196:embryology* / Q000235:genetics; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid
chemical_list: D029681:Arabidopsis Proteins; D005656:Fungal Proteins