ACTA2 and renal fibrosis: Proteins with the most significant age trends include HIST1H1B and other histones that are decreasing with age; increasing ACTA2 a marker gene for myofibroblasts and indicator of renal fibrosis (Duffield, 2014); decreasing NCLN, which is part of a complex in the endoplasmic reticulum (Haffner et al., 2007); and decreasing CISD2, which is involved in mitochondrial autophagy (Chen et al., 2009; Figure 3).