title: Immunolocalization of cell wall carbohydrate epitopes in seaweeds: presence of land plant epitopes in Fucus vesiculosus L. (Phaeophyceae).
abstract: Land plant cell wall glycan epitopes are present in Fucus vesiculosus. RG-I/AG mAbs recognize distinct glycan epitopes in structurally different galactans, and 3-linked glucans are also present in the cell walls. Cell wall-directed monoclonal antibodies (mAbs) have given increased knowledge of fundamental land plant processes but are not extensively used to study seaweeds. We profiled the brown seaweed Fucus vesiculosus glycome employing 155 mAbs that recognize predominantly vascular plant cell wall glycan components. The resulting profile was used to inform in situ labeling studies. Several of the mAbs recognized and bound to epitopes present in different thallus parts of Fucus vesiculosus. Antibodies recognizing arabinogalactan epitopes were divided into four groups based on their immunolocalization patterns. Group 1 bound to the stipe, blade, and receptacles. Group 2 bound to the antheridia, oogonia and paraphyses. Group 3 recognized antheridia cell walls and Group 4 localized on the antheridia inner wall and oogonia mesochite. This study reveals that epitopes present in vascular plant cell walls are also present in brown seaweeds. Furthermore, the diverse in situ localization patterns of the RG-I/AG clade mAbs suggest that these mAbs likely detect distinct epitopes present in structurally different galactans. In addition, 3-linked glucans were also detected throughout the cell walls of the algal tissues, using the β-glucan-directed LAMP mAb. Our results give insights into cell wall evolution, and diversify the available tools for the study of brown seaweed cell walls.
authors.affiliation: Botany and Plant Science and Ryan Institute for Environmental, Marine and Energy Research, School of Natural Sciences, National University of Ireland Galway, Galway, Ireland. s.raimundo1@nuigalway.ie.|Complex Carbohydrate Research Center, University of Georgia, Athens, GA, 30602, USA. s.raimundo1@nuigalway.ie.
authors.forename: Sandra Cristina
authors.initials: SC
authors.lastname: Raimundo
authors.affiliation: Complex Carbohydrate Research Center, University of Georgia, Athens, GA, 30602, USA. uavci@ccrc.uga.edu.
authors.forename: Utku
authors.initials: U
authors.lastname: Avci
authors.affiliation: Complex Carbohydrate Research Center, University of Georgia, Athens, GA, 30602, USA. clh1977@uga.edu.
authors.forename: Christina
authors.initials: C
authors.lastname: Hopper
authors.affiliation: Complex Carbohydrate Research Center, University of Georgia, Athens, GA, 30602, USA. siva@ccrc.uga.edu.
authors.forename: Sivakumar
authors.initials: S
authors.lastname: Pattathil
authors.affiliation: Complex Carbohydrate Research Center, University of Georgia, Athens, GA, 30602, USA. hahn@ccrc.uga.edu.
authors.forename: Michael G
authors.initials: MG
authors.lastname: Hahn
authors.affiliation: Botany and Plant Science and Ryan Institute for Environmental, Marine and Energy Research, School of Natural Sciences, National University of Ireland Galway, Galway, Ireland. zoe.popper@nuigalway.ie.
authors.forename: Zoë A
authors.initials: ZA
authors.lastname: Popper
mesh_terms: D000941:Antigens / Q000032:analysis*; D002473:Cell Wall / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D044645:Fucus / Q000378:metabolism*; D054794:Glycomics; D007150:Immunohistochemistry; D010944:Plants / Q000276:immunology
chemical_list: D000941:Antigens
keywords: 3-Linked glucan; Brown seaweed; Cell wall; Galactans; Glycome profiling; Monoclonal antibodies