The junction of the signal peptides and mature polypeptides for both avenins and globulins was determined by comparison of derived amino acid sequences from the DNA contigs to sequenced oat proteins and related proteins from other cereals. Comparisons of sequences was using MEGA 5.10 and ClustalW for alignments and the Neighbor-joining algorithm for phylogenetic tree generation. Validity of the generated trees were checked by bootstrap with 500 iterations. Alignments were checked manually and adjusted as needed – particularly within repetitive regions where alignment algorithms have difficulty with prolamins. It is proposed to consider the structure of these avenins to be composed of seven domains. The first domain is the signal peptide cleaved during protein Ruxolitinib processing. This is followed by six domains of the mature avenin. The first domain is a 22–26 residue relatively conserved sequence followed by a domain especially high in glutamine plus a number of proline and leucine residues. Domain III is 75 residue positions of conserved sequence followed by a second domain high in glutamine, proline, and leucine. The C-terminal portion of the avenins includes a third conserved domain of 24 residues and the polypeptide ending with 10 or 15 non-conserved amino acid residues. The intramolecular disulfide bonds of an avenin similar to Avenins 5-7 have been previously reported and the pattern of bonds is assumed to be similar in all other avenins. These eight conserved cysteine residues that form four intramolecular disulfide bridges are typical of portions of the basic pattern of the AAI_LTSS protein superfamily. Two of the avenins, Avenin-8 and Avenin-9, have a ninth cysteine as their C-terminal amino acid – presumably available for intermolecular disulfide bonds. The nine CDC Dancer avenin sequences were also compared to other known full-length A. sativa avenin protein sequences and found to cluster well with branches including the other 67 sequences from a variety of A. sativa germplasms. This result indicates no additional major subclasses of active avenins genes likely exist in cv CDC Dancer with the variations in sequence indicated in Figure S1 being consistent with variation among the different alleles and complements from different germplasms. The alignment of CDC Dancer avenins was used to generate a phylogenetic tree whose branches suggest three groupings; i.e., Avenins 1-4, 6-7, and 8-9. Unique features of these groupings can be seen where red horizontal lines separate the three groupings. Distinguishing features of the three groupings include mature Avenins 5–7 beginning with an additional four amino acids compared to the other two groupings, Avenins 8–9 having five additional amino acids in domain VI, and the three different surrounding residue contexts for cysteine-3 at position 138. Although results clearly indicate at least three main branches, there is evidence that Avenin-4 may belong in either its own branch or at least counted as a variant of the top branch.