Figure 7.

TaBCAT1 localizes to the mitochondria where it may regulate BCAA levels that correspond to Pst susceptibility during infection. A, TaBCAT1-A co-localized with the mitochondrial marker ScCOX4. TaBCAT1:GFP and ScCOX4:RFP were transiently co-expressed in N. benthamiana and images captured 2-day post-infiltration. White arrowheads highlight overlapping GFP and RFP signals in mitochondria. Images are representative of >10 images captured, which all displayed co-localization of TaBCAT1:GFP and ScCOX4:RFP. Left panels, individual TaBCAT1:GFP (top) and ScCOX4:RFP (bottom) localization patterns, right panel, TaBCAT1:GFP and ScCOX4:RFP merged image illustrating co-localization. Scale bar represents 10 µm. B, Several BCAAs and Asp-derived amino acids were enhanced in TaBCAT1-A^Q50* TaBCAT1-B^R366- (n = 4) compared to Kronos wild type (n = 5). Val, Thr, and Lys displayed a significant increase in the double mutant. C, The level of the BCAAs Val, Leu, and Ile and the Asp-derived amino acid Thr were significantly increased at 24 hpi in the resistant variety Santiago (n = 5) during Pst infection (isolate F22) when compared to the susceptible variety Oakley (n = 5). The level of the BCAAs and Asp-derived amino acids were assessed at 12, 24, and 48 hpi. Asterisks denote statistically significant differences (***p < 0.001, *p < 0.05; two-tailed t test). Bars represent median values, boxes signify the upper (Q3) and lower (Q1) quartiles, and whiskers are located at 1.5 the interquartile range