Fig. 1

Ahnak, as a major binding partner of the p11/Anxa2 complex, stabilizes p11 and Anxa2 proteins. a GST, GST-p11, or GST-p11/Anxa2 peptide hybrid was incubated without (−) or with ( + ) detergent extract of rat brain. After precipitation of GST proteins by glutathione-agarose, total brain extract protein (Input) and co-precipitated proteins were analyzed in SDS-PAGE. A major protein selectively co-precipitated with GST-p11/Anxa2 peptide hybrid (arrowhead) was identified as Ahnak by mass spectrometry. b Co-precipitation of Ahnak in the GST pulldown assay was validated by immunoblotting with anti-Ahnak antibody. c A detergent-soluble fraction from mouse brain was used for immunoprecipitation with control IgG or anti-Ahnak antibody. p11 and Anxa2 were co-precipitated with Ahnak. Asterisks indicate IgG. d-g Protein levels of p11 and Anxa2 in the hippocampus (d, e) or PFC (f, g) of WT and Ahnak KO mice were analyzed. Representative images of immunoblotting (d, f) and quantification of protein levels (e, g) are shown (n = 7 per group). Bars are means ± SEM. **p < 0.01, ***p < 0.001, t test. h–k Comparison of protein levels of Ahnak, p11, and Anxa2 in the brain. Representative images of immunoblotting (h, j) and comparison plot for Ahnak versus p11, Ahnak versus Anxa2, and p11 versus Anxa2 (i, k) in the hippocampus (h, i) or PFC (j, k) of naïve WT mice. Protein levels of Ahnak, p11, and Anxa2 are positively correlated in an individual brain tissue (n = 29). XY comparisons. Pearson’s correlation coefficient, r