APP and Alzheimer disease: To investigate the role of protein Kbhb in AD, we conducted 4D label‐free Kbhb quantitative proteomics in four groups of mice (Figure 1c), which include 8‐month‐old APP/PS1 mice that exhibit marked Aβ plaque burdens and cognitive impairment, 2‐month‐old APP/PS1 mice that have little Aβ plaques and no cognitive impairment (Gengler et al., 2010; Radde et al., 2006; Serneels et al., 2009), and 2‐month‐old and 8‐month‐old littermate WT mice.