Your browser doesn't support javascript.
loading
Barley "uzu" and Wheat "uzu-like" Brassinosteroid Receptor BRI1 Kinase Domain Variations Modify Phosphorylation Activity In Vitro.
Demissie, Zerihun A; Huang, Fang; Song, Halim; Todd, Andrea T; Vrinten, Patricia; Loewen, Michele C.
Afiliação
  • Demissie ZA; National Research Council of Canada, 100 Sussex Drive, Ottawa, ON K1A 0R6, Canada.
  • Huang F; National Research Council of Canada, 100 Sussex Drive, Ottawa, ON K1A 0R6, Canada.
  • Song H; National Research Council of Canada, 110 Gymnasium Place, Saskatoon, SK S7N 0W9, Canada.
  • Todd AT; National Research Council of Canada, 110 Gymnasium Place, Saskatoon, SK S7N 0W9, Canada.
  • Vrinten P; National Research Council of Canada, 110 Gymnasium Place, Saskatoon, SK S7N 0W9, Canada.
  • Loewen MC; National Research Council of Canada, 100 Sussex Drive, Ottawa, ON K1A 0R6, Canada.
Biochemistry ; 59(32): 2986-2997, 2020 08 18.
Article em En | MEDLINE | ID: mdl-32786402
Brassinosteroid insensitive1 (BRI1), a leucine-rich repeat receptor kinase, is responsible for the perception of the brassinosteroid (BR) phytohormone in plants. While recent evidence has implicated a naturally occurring Hordeum vulgare V. (barley) HvBRI1 kinase domain (KD) variant (H857R; "uzu" variation) in increased fungal disease resistance, the impact of the variation on receptor function and thus the mechanism by which disease resistance might be imparted remain enigmatic. Here, the functional implications of the uzu variation as well as the effects of newly identified naturally occurring Triticum aestivum L. (wheat) TaBRI1-KD variants are investigated. Recombinantly produced KDs of wild-type (WT) and uzu HvBRI1 were assessed for phosphorylation activity in vitro, yielding WT KM and VMAX values similar to those of other reports, but the uzu variation delayed saturation and reduced turnover levels. In silico modeling of the H857R variation showed it to be surface-exposed and distal from the catalytic site. Further evaluation of three naturally occurring wheat TaBRI1 variants, A907T, A970V, and G1019R (barley numbering) identified in the A, B, and D subgenomic genes, respectively, highlighted a significant loss of activity for A907T. A907T is located on the same surface as the H857R variation and a negative regulatory phosphorylation site (T982) in Arabidopsis thaliana BRI1. A fourth variation, T1031A (barley numbering), unique to both subgenomic A proteins and localized to the BKI1 binding site, also decreased activity. The outcomes are discussed with respect to the predicted structural contexts of the variations and their implications with respect to mechanisms of action.
Assuntos

Texto completo: 1 Coleções: 01-internacional Base de dados: MEDLINE Assunto principal: Proteínas Quinases / Hordeum / Triticum Tipo de estudo: Prognostic_studies Idioma: En Revista: Biochemistry Ano de publicação: 2020 Tipo de documento: Article País de afiliação: Canadá País de publicação: Estados Unidos

Texto completo: 1 Coleções: 01-internacional Base de dados: MEDLINE Assunto principal: Proteínas Quinases / Hordeum / Triticum Tipo de estudo: Prognostic_studies Idioma: En Revista: Biochemistry Ano de publicação: 2020 Tipo de documento: Article País de afiliação: Canadá País de publicação: Estados Unidos