Fig. 4: TaWD40-4B.1^C but not TaWD40-4B.1^T promotes in vivo and in vitro activity and oligomerization of catalase.

a The catalase activities in the leaves of cultivar SR3 and its transgenic lines under the well-watered and water-withheld conditions (n = 9 biologically independent samples; P = 6.36 × 10⁻⁵⁹). Box indicates the range from lower to upper quartiles, and the bar ranges the minimum to maximum observations. SR3: the cultivar carrying TaWD40-4B.1^C; OE-T: TaWD40-4B.1^T overexpression lines; OE-C: TaWD40-4B.1^C overexpression lines; RNAi: TaWD40-4B.1^C RNAi lines. b The ectopic expression of TaWD40-4B.1^C/TaWD40-4B.1^T and/or TaCAT3A in yeast confirmed by the western blotting assay. c The catalase activities of the yeast cells ectopically expressing TaWD40-4B.1^C/TaWD40-4B.1^T and/or TaCAT3A (n = 3 biologically independent samples; P = 1.60 × 10⁻¹⁰). d The growth rates of the yeast cells ectopically expressing TaWD40-4B.1^C/TaWD40-4B.1^T and/or TaCAT3A under the control and H₂O₂-treated conditions (n = 3 biologically independent samples). e TaWD40-4B.1^C promotes in vitro activity of TaCAT3A (n = 5 biologically independent samples). f TaCAT1A and TaCAT3A interact with themselves. g TaWD40-4B.1^C promotes the interaction of TaCAT1A-TaCAT1A and TaCAT3A-TaCAT3A. h The monomer, dimer, and oligomer of catalases are detected in the cross-linked proteins by DSP extracted from wheat seedlings, but the dimer and oligomer are not detected in the proteins when the cross-links are cleaved by β-ME. i The oligomerization of catalases is promoted by TaWD40-4B.1^C in vitro. The assay is the same as h using the proteins from in vitro catalase activity assay system. In c–e, data are shown as mean and standard deviation. In a, c, the significance of the difference is calculated with a one-way ANOVA analysis–Tukey comparison, and the columns labeled without the same alphabet are significantly different (P < 0.05, two-sided). Source data are provided as a Source data file.