title: Promoter analysis and immunolocalisation show that puroindoline genes are exclusively expressed in starchy endosperm cells of wheat grain.
abstract: The purolindolines are small cysteine-rich proteins which are present in the grain of wheat. They have a major impact on the utilisation of the grain as they are the major determinants of grain texture, which affects both milling and baking properties. Bread and durum wheats were transformed with constructs comprising the promoter regions of the Puroindoline a (Pina) and Puroindoline b (Pinb) genes fused to the uidA (GUS) reporter gene. Nine lines showing 3:1 segregation for the transgene and comprising all transgene/species combinations were selected for detailed analysis of transgene expression during grain development. This showed that transgene expression occurred only in the starchy endosperm cells and was not observed in any other seed or vegetative tissues. The location of the puroindoline proteins in these cells was confirmed by tissue printing of developing grain, using a highly specific monoclonal antibody for detection and an antibody to the aleurone-localised 8S globulin as a control. This provides clear evidence that puroindolines are only synthesised and accumulated in the starchy endosperm cells of the wheat grain.
authors.affiliation: Rothamsted Research, Harpenden, Hertfordshire, AL5 2JQ, UK.
authors.forename: Paul R
authors.initials: PR
authors.lastname: Wiley
authors.forename: Paola
authors.initials: P
authors.lastname: Tosi
authors.forename: Alexandre
authors.initials: A
authors.lastname: Evrard
authors.forename: Alison
authors.initials: A
authors.lastname: Lovegrove
authors.forename: Huw D
authors.initials: HD
authors.lastname: Jones
authors.forename: Peter R
authors.initials: PR
authors.lastname: Shewry
mesh_terms: D005966:Glucuronidase / Q000032:analysis; D007150:Immunohistochemistry; D010940:Plant Proteins / Q000032:analysis / Q000235:genetics*; D011401:Promoter Regions, Genetic; D011993:Recombinant Fusion Proteins / Q000032:analysis; D012639:Seeds / Q000166:cytology / Q000235:genetics / Q000378:metabolism; D014170:Transformation, Genetic; D014908:Triticum / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*
chemical_list: D010940:Plant Proteins; D011993:Recombinant Fusion Proteins; C082942:puroindoline protein, Triticum aestivum; D005966:Glucuronidase