Supplementary Figure 2: Generation of microglia-specific TRAP mice.

(a) Analysis of previously described microglia-specific Cre mouse lines revealed non-exclusive and/or incomplete targeting of microglia in the adult mouse brain for many of the tested Cre-lines (summarized in table). GFP/YFP: green; microglial marker, IBA1: red; and DAPI: blue from cerebellum and striatum of Tg(Prox1-Cre)SJ39; Eef1a1^{LSLeGFPL10a/+}, Tg(Csf1r-iCre);R26^LSL.eYFP/+, Tg(Csf1r-Cre/Esr1*);Eef1a1^{LSLeGFPL10a/+}, and Tg(Vav1-iCre);Eef1a1^{LSLeGFPL10a/+} mice are shown. Scale: 20 μm. Tg(Csf1r-iCre) and Tg(Vav1-iCre) lines were excluded due to neuronal targeting in brain regions of interest. Tg(Csf1r-Cre/Esr1*) line was excluded due to neuronal targeting and insufficient labeling of microglia. Tg(Prox1-Cre)SJ39 line exhibited exclusive and complete microglia targeting in a limited number brain regions (cerebellum, striatum, and cortex) and was used as an alternative line to target microglia in these regions. Arrows indicate non-microglial targeting. (b) Microglia-specific GFP expression in the striatum, cerebellum, brain stem, and dentate gyrus of Cx3cr1^{CreErt2/+(Litt)};Eef1a1^{LSLeGFPL10a/+} mice. Scale: 20 μm. Top: GFP/YFP: green; IBA1+ microglia: red; and DAPI: blue; Bottom: GFP/YFP+ cells: green; NeuN+ neurons (left): red or GFAP+ astrocytes/Bergmann glia (right): red; and DAPI: blue. (c) Expression of eGFP-L10a protein across the microglial cell body, including protrusions, is visualized in Cx3cr1^{CreErt2/+(Jung)};Eef1a1^{LSLeGFPL10a/+} mice. GFP: green; IBA1+ microglia: red; and DAPI: blue from striatum and cerebellum of Cx3cr1^{CreErt2/+(Jung)};Eef1a1^{LSLeGFPL10a/+} mice. Scale: 10 μm. Representative immunofluorescence images from > 2 independent experiments are shown.