title: The starch-bound alpha-amylase/trypsin-inhibitors in Avena.
abstract: Oat kernels exhibit an extra-soft texture, a trait recently demonstrated to be largely modulated by starch-bound tryptophan-rich 2S proteins, the vromindolines. In this study, fractionation by two-dimensional electrophoresis of starch-bound proteins in 25 oat (Avena sativa) cultivars and 11 diploid or tetraploid Avena species revealed novel 2S proteins called Avena α-amylase/trypsin-inhibitors (AATI) because of their sequence similarity with wheat α-amylase/trypsin inhibitors. Thirty-seven AATI polypeptides, about 14 kDa in size, were split into three families named AATI-1, AATI-2, and AATI-3 with different primary structures and isoelectric points. AATI-1 and AATI-2 proteins showed 55.5-60.0 % sequence similarity with wheat α-amylase inhibitors CM1, CM2, and CM16, which have been found to cause innate immunity responses in celiac disease and non-celiac gluten sensitivity. Diploid A-genome and tetraploid AC-genome oat species possess three and five genes encoding for the AATI proteins, respectively, whereas hexaploid A. sativa exhibits 12 genes dispersed over the A-, C-, and D-genomes. Some AATI proteins expressed in hexaploid oats were assigned to the A-genome based on similarity to their counterparts in diploid species, contributing to further clarify the genetic origin of hexaploid oats. Moreover, AATI may interact with starch-bound vromindolines in determining the extra-soft texture of oat kernels and, due to their balanced amino acid compositions, may contribute to the biological value of oat proteins in a positive manner.
authors: Consiglio per la ricerca in agricoltura e l'analisi dell'economia agraria (CREA-QCE), Via Manziana 30, 00189, Rome, Italy. laura.gazza@crea.gov.it.
authors: Laura
authors: http://orcid.org/0000-0003-2772-3199
authors: L
authors: Gazza
authors: Consiglio per la ricerca in agricoltura e l'analisi dell'economia agraria (CREA-QCE), Via Manziana 30, 00189, Rome, Italy.
authors: Gloria
authors: G
authors: Gazzelloni
authors: Consiglio per la ricerca in agricoltura e l'analisi dell'economia agraria (CREA-QCE), Via Manziana 30, 00189, Rome, Italy.
authors: Federica
authors: F
authors: Taddei
authors: Consiglio per la ricerca in agricoltura e l'analisi dell'economia agraria (CREA-QCE), Via Manziana 30, 00189, Rome, Italy.|ENEA Research Center Casaccia, Via Anguillarese, 301, 00123, Rome, Italy.
authors: Arianna
authors: A
authors: Latini
authors: Department of Chemical Sciences, University of Catania, Via Andrea Doria 6, Catania, Italy.
authors: Vera
authors: V
authors: Muccilli
authors: Consiglio per la ricerca in agricoltura e l'analisi dell'economia agraria (CREA-MAC), Via Stezzano 24, Bergamo, Italy.
authors: Michela
authors: M
authors: Alfieri
authors: Consiglio per la ricerca in agricoltura e l'analisi dell'economia agraria (CREA-QCE), Via Manziana 30, 00189, Rome, Italy.
authors: Salvatore
authors: S
authors: Conti
authors: Consiglio per la ricerca in agricoltura e l'analisi dell'economia agraria (CREA-MAC), Via Stezzano 24, Bergamo, Italy.
authors: Rita
authors: R
authors: Redaelli
authors: Consiglio per la ricerca in agricoltura e l'analisi dell'economia agraria (CREA-QCE), Via Manziana 30, 00189, Rome, Italy.
authors: Norberto E
authors: NE
authors: Pogna
mesh_terms: D018554:Avena / Q000235:genetics* / Q000378:metabolism; D004171:Diploidy; D018745:Genome, Plant; D010940:Plant Proteins / Q000235:genetics / Q000302:isolation & purification; D011123:Polyploidy; D017422:Sequence Analysis, DNA; D012689:Sequence Homology, Nucleic Acid; D013213:Starch / Q000378:metabolism; D014361:Trypsin Inhibitors / Q000302:isolation & purification*; D000516:alpha-Amylases / Q000235:genetics / Q000302:isolation & purification*
chemical_list: D010940:Plant Proteins; D014361:Trypsin Inhibitors; D013213:Starch; D000516:alpha-Amylases
keywords: Avena; Kernel texture; Oat immunogenicity; Starch-bound proteins; α-Amylase/trypsin-inhibitors