Fig. 1: CATS.
From: Imaging brain tissue architecture across millimeter to nanometer scales
a, Platform for tissue analysis including live extracellular labeling (coCATS) or extracellular labeling in previously fixed tissue (rCATS), optional molecular staining, super-resolved acquisition and conventional/machine learning analysis. b, Top: coCATS labeling (STAR RED-NHS) in organotypic hippocampal slice, revealing gross architecture of the DG and CA3 region and zoomed view of boxed region (confocal). Data are representative of experiments in n = 10 slices. Raw data. Intensity lookup tables for CATS are inverted throughout—that is, black regions correspond to high labeling intensity, unless otherwise noted. Bottom: rCATS labeling (WGA-CF633) in perfusion-fixed adult mouse coronal section, showing hippocampus with zoomed view. Raw data. Data are representative of rCATS in n = 10 fixative perfused animals. c, Progressive zoom from hippocampal regional to cellular scale in CA3 stratum pyramidale and stratum lucidum. coCATS labeling by in vivo stereotactic injection (STAR RED-NHS) into the LV of adult mouse (left: lookup table not inverted; left bottom: gamma correction applied). Left, center: confocal; right: STED, lateral resolution increase (xy-STED). Raw data. d, Super-resolved tissue architecture of mouse CA3 stratum pyramidale/lucidum, after in vivo coCATS label (STAR RED-NHS) microinjection into LV. Left top: immunostaining of pre-synaptic BASSOON (magenta, confocal, AF488) and post-synaptic SHANK2 (turquoise, xy-STED, AF594). Left bottom: coCATS (xy-STED) of same region. Right: overlay placing synaptic markers into structural context, including MFBs. Raw data. Images are representative of coCATS with in vivo microinjection into the LV in n = 10 animals. e, Magnified view from d (boxed), focusing on an MFB with multiple synaptic sites, amidst bundles of thin mossy fiber axons. Inset: magnification of synaptic transmission site. High-intensity coCATS labeling pinpoints dense/protein-rich features between pre-synapses and post-synapses corresponding to pSCRs. f, Line profile as indicated in e, showing sandwich arrangement of BASSOON, high-intensity coCATS (pSCR) and SHANK2 signals.
