Fig. 5: PC core protein levels are reduced during brain aging, and their restoration is sufficient to improve age-related memory decline.
From: A primary cilia–autophagy axis in hippocampal neurons is essential to maintain cognitive resilience
a, Relative expression of Ift20, Ift25, Ift88 and Kif3a in WT dorsal mouse hippocampi at 3, 6, 12, 16 and 23 months of age. Quantification of mRNA expression is relative to the 3-month-old WT mouse group (n = 6 per group except for 23-month-old where n = 5 for ift20, n = 5 for Ift88 and n = 4 for Kif3A). b, Representative western blot of IFT20, IFT88 and KIF3A protein levels in WT dorsal mouse hippocampi at 3, 6, 12 and 16 months of age. c, PC immunofluorescent staining (green, stained by ACIII) in the CA3 region of the hippocampus of young (3-month-old) and aged (16-month-old) mice. The length of the PC was measured and quantified in 3D using Imaris software. Scale bar, 5 µm. d, Western blot image and quantification of IFT20 protein in 3-month-old or 16-month-old mice, 3 weeks after stereotactic injections with either AAV-GFP (control) or AAV-mIft20 (expressing mouse Ift20 cDNA). e, Western blot images and quantification of IFT25, IFT88 and KIF3A levels in the same experimental groups as in d. These measurements were performed in two independent experiments. f, LC3B and SQSTM1/p62 immunofluorescence (LC3B in red and p62 in green) and puncta quantification performed on brain cross-sections, at the level of the hippocampal CA3 region of 3-month-old or 16-month-old mice, 3 weeks after stereotactic injections with AAV-GFP (control) or AAV-mIft20 cDNA. Scale bars, 20 µm. g, NOR performed in 3-month-old or 16-month-old mice, after hippocampal stereotactic injections with AAV-GFP (control) or AAV-mIft20 cDNA. Discrimination and preference indexes were measured 24 h after the training phase to assess memory performances. The NOR was performed in two independent experiments for each group of mice. β-actin was used as a loading control for each sample in all western blot analyses. Data are expressed as mean ± s.e.m., and P values were determined by one-tailed (f) or two-tailed (c–e) Student’s t-tests or by one-way ANOVA (a, g). Mo, month-old.
