title: Arabinogalactan proteins are involved in root hair development in barley.
abstract: The arabinogalactan proteins (AGPs) are involved in a range of plant processes, including cell differentiation and expansion. Here, barley root hair mutants and their wild-type parent cultivars were used, as a model system, to reveal the role of AGPs in root hair development. The treatment of roots with different concentrations of βGlcY (a reagent which binds to all classes of AGPs) inhibited or totally suppressed the development of root hairs in all of the cultivars. Three groups of AGP (recognized by the monoclonal antibodies LM2, LM14, and MAC207) were diversely localized in trichoblasts and atrichoblasts of root hair-producing plants. The relevant epitopes were present in wild-type trichoblast cell walls and cytoplasm, whereas in wild-type atrichoblasts and in all epidermal cells of a root hairless mutant, they were only present in the cytoplasm. In all of cultivars the higher expression of LM2, LM14, and MAC207 was observed in trichoblasts at an early stage of development. Additionally, the LM2 epitope was detected on the surface of primordia and root hair tubes in plants able to generate root hairs. The major conclusion was that the AGPs recognized by LM2, LM14, and MAC207 are involved in the differentiation of barley root epidermal cells, thereby implying a requirement for these AGPs for root hair development in barley.
authors.affiliation: Department of Genetics, Faculty of Biology and Environmental Protection, University of Silesia, Katowice 40-032, Poland marek.marzec@us.edu.pl.
authors.forename: Marek
authors.initials: M
authors.lastname: Marzec
authors.affiliation: Department of Genetics, Faculty of Biology and Environmental Protection, University of Silesia, Katowice 40-032, Poland.
authors.forename: Iwona
authors.initials: I
authors.lastname: Szarejko
authors.affiliation: Department of Physiology and Cell Biology, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Gatersleben D-06466, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Melzer
mesh_terms: D002454:Cell Differentiation; D018506:Gene Expression Regulation, Plant; D001467:Hordeum / Q000166:cytology / Q000235:genetics / Q000378:metabolism*; D009088:Mucoproteins / Q000235:genetics / Q000378:metabolism*; D019441:Plant Epidermis / Q000166:cytology / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D018517:Plant Roots / Q000166:cytology / Q000254:growth & development* / Q000378:metabolism
chemical_list: D009088:Mucoproteins; D010940:Plant Proteins; C006619:arabinogalactan proteins
keywords: Arabinogalactan proteins (AGPs); Yariv.; barley (Hordeum vulgare); cell differentiation; monoclonal antibodies; root hairs