title: Early germination of Arabidopsis pollen in a double null mutant for the arabinogalactan protein genes AGP6 and AGP11.
abstract: The pollen specificity of the Arabidopsis arabinogalactan protein (AGP) genes AGP6 and AGP11 suggests that they are integral to pollen biogenesis, and their high percent of sequence similarity may indicate a potential for overlapping function. Arabidopsis agp6 agp11 double null mutants have been studied in our laboratory, and in the present work, we characterize the germination and growth of its pollen. When compared to wild type, mutant agp6 agp11 pollen displayed reduced germination and elongation, both in vivo and in vitro, and precocious germination inside the anthers, provided that sufficient moisture was available. This characteristic was not observed in wild type plants, even in water content conditions which for the mutant were sufficient for pollen germination. Therefore, an additional distinctive phenotypic trait of arabinogalactan proteins AGP6 and AGP11 may be to avert untimely germination of pollen. Such AGPs may control germination through water uptake, suggesting an important biological function of this gene family in pollen.
authors.affiliation: Departamento de Biologia, Faculdade de Ciências, Universidade do Porto, Edifício FC4 Rua do Campo Alegre s/n, 4169-007, Porto, Portugal. scoimbra@fc.up.pt
authors.forename: Sílvia
authors.initials: S
authors.lastname: Coimbra
authors.forename: Mário
authors.initials: M
authors.lastname: Costa
authors.forename: Marta Adelina
authors.initials: MA
authors.lastname: Mendes
authors.forename: Ana Marta
authors.initials: AM
authors.lastname: Pereira
authors.forename: João
authors.initials: J
authors.lastname: Pinto
authors.forename: Luís Gustavo
authors.initials: LG
authors.lastname: Pereira
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D018525:Germination; D009154:Mutation; D011058:Pollen / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D011509:Proteoglycans / Q000235:genetics* / Q000378:metabolism; D014867:Water / Q000378:metabolism
chemical_list: C544319:AGP11 protein, Arabidopsis; C544318:AGP6 protein, Arabidopsis; D029681:Arabidopsis Proteins; D011509:Proteoglycans; D014867:Water