TY - JOUR
T1 - Wheat glutenin
T2 - the “tail” of the 1By protein subunits
AU - Nunes-Miranda, Júlio D.
AU - Bancel, Emmanuelle
AU - Viala, Didier
AU - Chambon, Christophe
AU - Capelo, José L.
AU - Branlard, Gérard
AU - Ravel, Catherine
AU - Igrejas, Gilberto
N1 - Sem PDF.
PY - 2017/10/3
Y1 - 2017/10/3
N2 - Gluten-forming storage proteins play a major role in the viscoelastic properties of wheat dough through the formation of a continuous proteinaceous network. The high-molecular-weight glutenin subunits represent a functionally important subgroup of gluten proteins by promoting the formation of large glutenin polymers through interchain disulphide bonds between glutenin subunits. Here, we present evidences that y-type glutenin subunits encoded at the Glu-B1 locus are prone to proteolytic processing at the C-terminus tail, leading to the loss of the unique cysteine residue present at the C-terminal domain. Results obtained by intact mass measurement and immunochemistry for each proteoform indicate that the proteolytic cleavage appears to occur at the carboxyl-side of two conserved asparagine residues at the C-terminal domain start. Hence, we hypothesize that the responsible enzymes are a class of cysteine endopeptidases - asparaginyl endopeptidases - described in post-translational processing of other storage proteins in wheat. Biological significance The reported study provides new insights into wheat storage protein maturation. In view of the importance of gluten proteins on dough viscoelastic properties and end-product quality, the reported C-terminal domain cleavage of high-molecular-weight glutenin subunits is of particular interest, since this domain possesses a unique conserved cysteine residue which is assumed to participate in gluten polymerization.
AB - Gluten-forming storage proteins play a major role in the viscoelastic properties of wheat dough through the formation of a continuous proteinaceous network. The high-molecular-weight glutenin subunits represent a functionally important subgroup of gluten proteins by promoting the formation of large glutenin polymers through interchain disulphide bonds between glutenin subunits. Here, we present evidences that y-type glutenin subunits encoded at the Glu-B1 locus are prone to proteolytic processing at the C-terminus tail, leading to the loss of the unique cysteine residue present at the C-terminal domain. Results obtained by intact mass measurement and immunochemistry for each proteoform indicate that the proteolytic cleavage appears to occur at the carboxyl-side of two conserved asparagine residues at the C-terminal domain start. Hence, we hypothesize that the responsible enzymes are a class of cysteine endopeptidases - asparaginyl endopeptidases - described in post-translational processing of other storage proteins in wheat. Biological significance The reported study provides new insights into wheat storage protein maturation. In view of the importance of gluten proteins on dough viscoelastic properties and end-product quality, the reported C-terminal domain cleavage of high-molecular-weight glutenin subunits is of particular interest, since this domain possesses a unique conserved cysteine residue which is assumed to participate in gluten polymerization.
KW - 1By HMW-GS
KW - Asparagine
KW - Asparaginyl endopeptidase
KW - C-terminal domain maturation
KW - Proteolytic cleavage
KW - Wheat glutenin
UR - http://www.scopus.com/inward/record.url?scp=85020116028&partnerID=8YFLogxK
U2 - 10.1016/j.jprot.2017.05.019
DO - 10.1016/j.jprot.2017.05.019
M3 - Article
AN - SCOPUS:85020116028
SN - 1874-3919
VL - 169
SP - 136
EP - 142
JO - Journal of Proteomics
JF - Journal of Proteomics
ER -