Trio localizes to synapses in cultured hippocampal neurons.

<p>(A, B, and C) Images of 16–19 DIV neurons fixed in methanol and immunostained for the proteins indicated. Arrows depict puncta of either Piccolo or Synaptophysin that are positive for PSD-95 and, thus, likely excitatory synapses that were also immune-positive for Trio. Arrowheads depict puncta of Piccolo or Synaptophysin that were negative for PSD-95 (and thus either inhibitory synapse or transport vesicles) that were also Trio positive. Insets in A-C show higher mag regions of boxed areas. (D) Quantification of Trio puncta that colocalize with PSD-95 positive (+) or negative (-) puncta that were also positive for Piccolo or Synaptophysin puncta. Piccolo or Synaptophysin puncta were separated into PSD-95 positive (+) or negative (-) groups, which were then each scored as positive or negative for Trio. * = p < 0.0005, paired t test comparing PSD-95 positive (+) or PSD-95 negative (-) groups in individual images. n = 10 images for each group.