title: An ancient mechanism controls the development of cells with a rooting function in land plants.
abstract: Root hairs and rhizoids are cells with rooting functions in land plants. We describe two basic helix-loop-helix transcription factors that control root hair development in the sporophyte (2n) of the angiosperm Arabidopsis thaliana and rhizoid development in the gametophytes (n) of the bryophyte Physcomitrella patens. The phylogeny of land plants supports the hypothesis that early land plants were bryophyte-like and possessed a dominant gametophyte and later the sporophyte rose to dominance. If this hypothesis is correct, our data suggest that the increase in morphological complexity of the sporophyte body in the Paleozoic resulted at least in part from the recruitment of regulatory genes from gametophyte to sporophyte.
authors.affiliation: Department of Cell and Developmental Biology, John Innes Centre, Norwich NR47UH, UK.
authors.forename: Benoît
authors.initials: B
authors.lastname: Menand
authors.forename: Keke
authors.initials: K
authors.lastname: Yi
authors.forename: Stefan
authors.initials: S
authors.lastname: Jouannic
authors.forename: Laurent
authors.initials: L
authors.lastname: Hoffmann
authors.forename: Eoin
authors.initials: E
authors.lastname: Ryan
authors.forename: Paul
authors.initials: P
authors.lastname: Linstead
authors.forename: Didier G
authors.initials: DG
authors.lastname: Schaefer
authors.forename: Liam
authors.initials: L
authors.lastname: Dolan
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000166:cytology / Q000235:genetics / Q000254:growth & development / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000502:physiology*; D051792:Basic Helix-Loop-Helix Proteins / Q000235:genetics / Q000502:physiology*; D005075:Biological Evolution; D019068:Bryopsida / Q000166:cytology / Q000235:genetics / Q000254:growth & development / Q000502:physiology*; D004171:Diploidy; D017343:Genes, Plant; D006238:Haploidy; D008969:Molecular Sequence Data; D009154:Mutation; D010802:Phylogeny; D019441:Plant Epidermis / Q000166:cytology / Q000502:physiology; D010940:Plant Proteins / Q000235:genetics / Q000502:physiology; D018517:Plant Roots / Q000166:cytology* / Q000254:growth & development; D030821:Plants, Genetically Modified
chemical_list: D029681:Arabidopsis Proteins; D051792:Basic Helix-Loop-Helix Proteins; D010940:Plant Proteins; C520580:RHD6 protein, Arabidopsis; C520581:RSL1 protein, Arabidopsis