ASIC1a localization in dendritic spines. A) Immunofluorescence images showing the localization of endogenous ASIC1a in cultured neurons. Wild type (WT) and ASIC1a−/− cortical neurons were stained with an anti-ASIC1a antibody. Inset at the bottom shows a high magnification view of the boxed region in WT. Note the punctate staining along the dendrite, suggesting the presence of ASIC1a in dendritic spines. B) Confocal images showing the enrichment of ASIC1a in spines of slice neurons. Organotypic hippocampal slices were transfected with HA-ASIC1a and a membrane-targeted Lck-GFP. ASIC1a localization was detected by immunostaining with an anti-HA antibody. Plot on the right shows the relative fluorescence intensity of ASIC1a and Lck-GFP along the line drawn on the merged image. ASIC1a shows a higher relative spine:shaft signal as compared to Lck-GFP, demonstrating that ASIC1a preferentially traffics to dendritic spines. Data adapted from[19, 21].