cKO of Slc17a7 (VGLUT1) from cholinergic neurons in MHb. A, Schematic of KiaaCre; Rosa26ZSGreen reporter mouse line with Cre expression driven by Kiaa1107 regulatory elements and ZsGreen expression dependent on Cre recombination. B, Native ZsGreen fluorescence counterstained with DAPI in MHb (outlined); scale bar: 200 μm. C, Schematic of Cre recombination of the floxed Slc17a7 (VGLUT1) locus in the cKO (KiaaCre; Slc17a7flox/flox) mouse line. D, Fluorescent in situ hybridization of Cre, Chat, and Slc17a7 expression in MHb of control and cKO mice at two bregma points; scale bar: 100 μm. E, Higher-magnification images from white squares in D; scale bar: 50 μm. Densitometric quantification (without background subtraction) in ventral and dorsal MHb of (F) Cre, (G) Slc17a7 (VGLUT1), and (H) Chat signals. Only Slc17a7 was significantly reduced in ventral MHb of cKO (**p = 0.006); n = 3 mice per group.