Figure 1.

Changes in the expression of MeCP2 and MeCP2 pS421 in the adult mice striatum. (A,B) Alzheimer's disease (AD) mice striatum was collected at age of 3 months. Cytoplasmic proteins and nuclear proteins were extracted, respectively. Western blots were used to reveal MeCP2 and MeCP2 pS421 immunoreactivity and its normal controls. The data showed that MeCP2 selectively focused in the nucleus while MeCP2 pS421 in the cytoplasm. β-Tubulin and H3 were used for evaluating the loading control and the extracted purity of cytoplasmic and nuclear components severally. The specificity of the antibody to MeCP2 pS421 was validated by using both (A) PPTase and (B) phospho-MeCP2-S421 antibody-specific blocking peptide, and the immune-positive signals of MeCP2 pS421 was eliminated. The same PVDF membrane transfected with protein was used in this test. (C) Quantitative analysis revealed the decrease in MeCP2 expression levels in the nucleus and increase in MeCP2 pS421 expression levels in the cytoplasm in AD mice striatum. (D–G) Single immunostaining of MeCP2 and MeCP2 pS421 in the mice striatum. (D) MeCP2 was widely distributed in normal striatal cells. (E) AD injury reduced its immunoreactivity in the same viewing areas. While MeCP2 pS421 was detected highly in (G) AD mice striatal cells but barely in the (F) controls. (H) The blocking peptide eliminates the anti-phospho-MeCP2-S421 signals. (I) Negative control without primary antibody. (J) Diagram illustrates the region for observation [rectangle, (K)] (mean ± SEM, *P < 0.05 vs. control group mice, n = 6 in each group).