Fig. 4: Differential patterning of AST4 and AST5 in adult mouse brain.

Multiplexed fluorescence in situ hybridization was used to map locations of AST4 and AST5. a AST4 was identified by high expression levels of Frzb, Ascl1, and Slc1a3. b AST5 was identified by absence/low expression of Ogt and high expression of both Fam107a and Slc1a3. Mapping was performed on three sections obtained from three independent animals aged between P56–P60. Representative images are shown. Top left: low-magnification image of a coronal section. Black dots show the distribution of the astrocyte subtype through one brain hemisphere. Brain regions are defined manually based on definitions from the Allen Brain Atlas. High-magnification images (below) show the localization of markers to specific cells defined on the basis of nuclear (DAPI, blue) staining. Right: bar plots (showing from left to right) fluorescence counts per RNA marker per cell (shown for all cells across all sections analyzed), the distribution of the subtype between brain regions and the distribution of the subtype normalized to the total number of astrocytes per brain region (all Slc1a3 + cells). Astrocytes belonging to the subtype of interest are highlighted by a shaded box (color-coded according to the scheme used in Fig. 2a). Astrocyte numbers across layers are given as average per section analyzed. Error bars are equivalent across the figure and represent SEM. Scale bars, low magnification 1000 µm; high magnification, 10 µm. “+” high gene expression, “−” low or absent gene expression. SO Stratum oriens, SP Stratum pyramidale, SR Stratum radiatum, SG Subgranular zone, \DG Dentate gyrus without SG, SLM Stratum lacunosum-moleculare.