title: Seed filling in domesticated maize and rice depends on SWEET-mediated hexose transport.
abstract: Carbohydrate import into seeds directly determines seed size and must have been increased through domestication. However, evidence of the domestication of sugar translocation and the identities of seed-filling transporters have been elusive. Maize ZmSWEET4c, as opposed to its sucrose-transporting homologs, mediates transepithelial hexose transport across the basal endosperm transfer layer (BETL), the entry point of nutrients into the seed, and shows signatures indicative of selection during domestication. Mutants of both maize ZmSWEET4c and its rice ortholog OsSWEET4 are defective in seed filling, indicating that a lack of hexose transport at the BETL impairs further transfer of sugars imported from the maternal phloem. In both maize and rice, SWEET4 was likely recruited during domestication to enhance sugar import into the endosperm.
authors.affiliation: Department of Plant Biology, Carnegie Science, Stanford, California, USA.
authors.forename: Davide
authors.initials: D
authors.lastname: Sosso
authors.affiliation: Department of Genetics, Development and Cell Biology, Iowa State University, Ames, Iowa, USA.
authors.forename: Dangping
authors.initials: D
authors.lastname: Luo
authors.affiliation: US Department of Agriculture, Agricultural Research Service (USDA-ARS), Gainesville, Florida, USA.
authors.forename: Qin-Bao
authors.initials: QB
authors.lastname: Li
authors.affiliation: Department of Plant Biology, Carnegie Science, Stanford, California, USA.
authors.forename: Joelle
authors.initials: J
authors.lastname: Sasse
authors.affiliation: Department of Plant Sciences, University of California, Davis, Davis, California, USA.
authors.forename: Jinliang
authors.initials: J
authors.lastname: Yang
authors.affiliation: Ecole Normale Supérieure de Lyon, Université Lyon 1, Unité Reproduction et Développement des Plantes, Lyon, France.
authors.forename: Ghislaine
authors.initials: G
authors.lastname: Gendrot
authors.affiliation: Plant Molecular and Cellular Biology, Agronomy Department, University of Florida, Gainesville, Florida, USA.
authors.forename: Masaharu
authors.initials: M
authors.lastname: Suzuki
authors.affiliation: Plant Molecular and Cellular Biology, Agronomy Department, University of Florida, Gainesville, Florida, USA.
authors.forename: Karen E
authors.initials: KE
authors.lastname: Koch
authors.affiliation: Plant Molecular and Cellular Biology, Agronomy Department, University of Florida, Gainesville, Florida, USA.
authors.forename: Donald R
authors.initials: DR
authors.lastname: McCarty
authors.affiliation: US Department of Agriculture, Agricultural Research Service (USDA-ARS), Gainesville, Florida, USA.|Plant Molecular and Cellular Biology, Agronomy Department, University of Florida, Gainesville, Florida, USA.
authors.forename: Prem S
authors.initials: PS
authors.lastname: Chourey
authors.affiliation: Ecole Normale Supérieure de Lyon, Université Lyon 1, Unité Reproduction et Développement des Plantes, Lyon, France.
authors.forename: Peter M
authors.identifier: http://orcid.org/0000-0003-4822-3783
authors.initials: PM
authors.lastname: Rogowsky
authors.affiliation: Department of Plant Sciences, Center for Population Biology and Genome Center, University of California, Davis, Davis, California, USA.
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Ross-Ibarra
authors.affiliation: Department of Genetics, Development and Cell Biology, Iowa State University, Ames, Iowa, USA.
authors.forename: Bing
authors.initials: B
authors.lastname: Yang
authors.affiliation: Department of Plant Biology, Carnegie Science, Stanford, California, USA.
authors.forename: Wolf B
authors.initials: WB
authors.lastname: Frommer
mesh_terms: D001692:Biological Transport; D018556:Crops, Agricultural / Q000235:genetics*; D056625:Endosperm / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D006601:Hexoses / Q000378:metabolism*; D006801:Humans; D009154:Mutation / Q000235:genetics; D012275:Oryza / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D012639:Seeds / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D003313:Zea mays / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*
chemical_list: D006601:Hexoses; D010940:Plant Proteins