Extended Data Fig. 2: Mass spectrometry-based analysis of region-specific changes in Tfrc levels.

Following proteomic analysis of BECs from 18- vs 3-month-old mice, the signal intensity of Tfrc-related tryptic peptides was mapped onto the protein sequence. The mean intensity in samples from 3-month-old mice was set to 1. Significance was tested by Student´s t-test. The intracellular (aa 1–67), transmembrane (aa 68–88) and extracellular (aa 89–763) regions of Tfrc are labeled.