title: Regulatory function of homeodomain-leucine zipper (HD-ZIP) family proteins during embryogenesis.
abstract: Homeodomain-leucine zipper proteins (HD-ZIPs) form a plant-specific family of transcription factors functioning as homo- or heterodimers. Certain members of all four classes of this family are involved in embryogenesis, the focus of this review. They support auxin biosynthesis, transport and response, which are in turn essential for the apical-basal patterning of the embryo, radicle formation and outgrowth of the cotyledons. They transcriptionally regulate meristem regulators to maintain the shoot apical meristem once it is initiated. Some members are specific to the protoderm, the outermost layer of the embryo, and play a role in shoot apical meristem function. Within classes, homeodomain-leucine zippers tend to act redundantly during embryo development, and there are many examples of regulation within and between classes of homeodomain-leucine zippers. This indicates a complex network of regulation that awaits future experiments to uncover.
authors: Institute of Biology III, Albert-Ludwigs-Universität, Freiburg 79104, Germany.
authors: Farshad
authors: F
authors: Roodbarkelari
authors: Institute of Biology III, Albert-Ludwigs-Universität, Freiburg 79104, Germany.
authors: Edwin P
authors: EP
authors: Groot
mesh_terms: D018507:Gene Expression Regulation, Developmental; D018398:Homeodomain Proteins / Q000737:chemistry / Q000378:metabolism*; D007210:Indoleacetic Acids / Q000378:metabolism; D016350:Leucine Zippers; D018519:Meristem / Q000196:embryology; D010944:Plants / Q000196:embryology* / Q000235:genetics*
chemical_list: D018398:Homeodomain Proteins; D007210:Indoleacetic Acids
keywords: auxin; development; embryogenesis; homeodomain-leucine zipper proteins (HD-ZIPs); shoot apical meristem initiation; stem cell maintenance