title: Expression of arabinogalactan protein genes in pollen tubes of Arabidopsis thaliana.
abstract: The expression of "classical" arabinogalactan protein genes in pollen tubes of Arabidopsis thaliana was characterized by RT-PCR. Transcripts of Agp6 and Agp11 were consistently found to be more abundant in pollen tubes and seem to be pollen-specific. Transcripts of other AGP genes were also detected in pollen but in lesser amounts and in a non-specific fashion. Two reference genes, ubiquitin-conjugating enzyme 9 and tubulin beta-4 chain, were evaluated and selected for gene expression studies in pollen. Expression characterization was complemented with immunolocalization studies using monoclonal antibodies specific to several glycosidic epitopes of AGPs. These studies were performed on in vitro germinated pollen tubes with the antibodies MAC207 and LM2. MAC207 produced labelling at the tip of the pollen tube, while LM2 produced a ring-like fluorescence around the emerging region of the tube, suggesting a role of AGPs during Arabidopsis pollen tube germination. To our knowledge, this is the first report establishing the presence of AGPs on Arabidopsis pollen tubes.
authors.affiliation: Instituto de Biologia Molecular e Celular, Universidade do Porto, R. Campo Alegre 823 Porto, Portugal. lgpereir@ibmc.up.pt
authors.forename: Luís Gustavo
authors.initials: LG
authors.lastname: Pereira
authors.forename: Sílvia
authors.initials: S
authors.lastname: Coimbra
authors.forename: Hugo
authors.initials: H
authors.lastname: Oliveira
authors.forename: Lionel
authors.initials: L
authors.lastname: Monteiro
authors.forename: Mariana
authors.initials: M
authors.lastname: Sottomayor
mesh_terms: D000911:Antibodies, Monoclonal / Q000032:analysis; D017360:Arabidopsis / Q000033:anatomy & histology / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D015870:Gene Expression; D017343:Genes, Plant; D007150:Immunohistochemistry; D009088:Mucoproteins / Q000235:genetics / Q000378:metabolism*; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D011058:Pollen / Q000033:anatomy & histology / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D000911:Antibodies, Monoclonal; D029681:Arabidopsis Proteins; D009088:Mucoproteins; D010940:Plant Proteins; C006619:arabinogalactan proteins