title: Arabidopsis ANGULATA10 is required for thylakoid biogenesis and mesophyll development.
abstract: The chloroplasts of land plants contain internal membrane systems, the thylakoids, which are arranged in stacks called grana. Because grana have not been found in Cyanobacteria, the evolutionary origin of genes controlling the structural and functional diversification of thylakoidal membranes in land plants remains unclear. The angulata10-1 (anu10-1) mutant, which exhibits pale-green rosettes, reduced growth, and deficient leaf lateral expansion, resulting in the presence of prominent marginal teeth, was isolated. Palisade cells in anu10-1 are larger and less packed than in the wild type, giving rise to large intercellular spaces. The ANU10 gene encodes a protein of unknown function that localizes to both chloroplasts and amyloplasts. In chloroplasts, ANU10 associates with thylakoidal membranes. Mutant anu10-1 chloroplasts accumulate H2O2, and have reduced levels of chlorophyll and carotenoids. Moreover, these chloroplasts are small and abnormally shaped, thylakoidal membranes are less abundant, and their grana are absent due to impaired thylakoid stacking in the anu10-1 mutant. Because the trimeric light-harvesting complex II (LHCII) has been reported to be required for thylakoid stacking, its levels were determined in anu10-1 thylakoids and they were found to be reduced. Together, the data point to a requirement for ANU10 for chloroplast and mesophyll development.
authors.affiliation: Instituto de Bioingeniería, Universidad Miguel Hernández, Campus de Elche, 03202 Elche, Alicante, Spain.
authors.forename: Rubén
authors.initials: R
authors.lastname: Casanova-Sáez
authors.affiliation: Instituto de Bioingeniería, Universidad Miguel Hernández, Campus de Elche, 03202 Elche, Alicante, Spain.
authors.forename: Eduardo
authors.initials: E
authors.lastname: Mateo-Bonmatí
authors.affiliation: Department of Biochemistry and Food Chemistry, University of Turku, FI-20014 Turku, Finland.
authors.forename: Saijaliisa
authors.initials: S
authors.lastname: Kangasjärvi
authors.affiliation: Instituto de Bioingeniería, Universidad Miguel Hernández, Campus de Elche, 03202 Elche, Alicante, Spain.
authors.forename: Héctor
authors.initials: H
authors.lastname: Candela
authors.affiliation: Instituto de Bioingeniería, Universidad Miguel Hernández, Campus de Elche, 03202 Elche, Alicante, Spain jlmicol@umh.es.
authors.forename: José Luis
authors.initials: JL
authors.lastname: Micol
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D002734:Chlorophyll / Q000378:metabolism; D002736:Chloroplasts / Q000378:metabolism; D058503:Mesophyll Cells / Q000378:metabolism*; D018515:Plant Leaves / Q000254:growth & development* / Q000378:metabolism; D060431:Thylakoid Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D020524:Thylakoids / Q000378:metabolism*
chemical_list: C000594289:ANU10 protein, Arabidopsis; D029681:Arabidopsis Proteins; D060431:Thylakoid Membrane Proteins; D002734:Chlorophyll
keywords: Arabidopsis thaliana; LHCII trimers; chloroplast; grana; mesophyll development; thylakoid biogenesis; thylakoid stacking.