Fig. 3

Stronger labeling intensity and higher tracing efficiency of H129-dgK-G4. A. Schematic genome structure of H129-dTK-G4. B-C. Comparison of labeling intensity between H129-dgK-G4 and H129-dTK-G4. H129-dgK-G4 and H129-dTK-G4 alone were injected into the CA1 of wildtype C57BL/6 mice with the same dosage (5.0 × 10⁸ pfu/ml, 100 nl) respectively, and the brains were collected one day later. The representative images from 3 mice of each group are shown (B). The labeling intensity of the GFP⁺ neurons was measured and analyzed by Image J software, and quantitated as the average brightness of the labeled neurons (AU, arbitrary unit). 3 position-matched slices from each mouse and 3 mice per group were applied for the analysis. Statistical significance was analyzed by Student’s t-test. ***, p < 0.001(C). D-E. Comparison of the transneuronal labeling efficiency between H129-dgK-G4 and H129-dTK-G4. The appropriate AAV helper virus (1.0 × 10¹² vg/ml, 150 nl) and H129-derived monosynaptic tracer (5.0 × 10⁸ pfu/ml, 150 nl) of H129-dgK-G4 or H129-dTK-G4 were sequentially injected into the olfactory bulb (OB) of wildtype C57BL/6 mice at day 1 and day 22, and the brains were perfused and collected at day 27. The representative images of the projecting region of the piriform cortex (Pir) from 3 mice of each group are shown (D). The number of GFP-labeled neurons in Pir of each position-matched brain slice was counted. Statistical significance was determined by linear mixed-effect model (LME) analysis. ***, p < 0.001 (E)