Fig. 7.

Ectopic NR4A1 caused the loss of mitochondria and dendritic spine clusters.

A. Doxycycline-dependent expression of NR4A1 with a constitutive GFP reporter in layer 2/3 pyramidal neurons of somatosensory cortex (2 mg/ml dox in drinking water for 14 days).

B. Two-photon images of dendritic Mito-dsRed and GFP in pyramidal neurons electroporated with dox-dependent NR4A1. A distance ≤5 μm is indicated where the loss of dendritic spine clusters corresponded with the loss of mitochondrial coverage.

C. Topography of mitochondria and spine remodeling in dendritic territories imaged twice 14 days apart ± dox.

D. Clustered spine dynamics ON dox is greater than chance. Histogram shows the distribution of spine permutations in 30,000 simulations of randomized new spine positions (mean Gaussian fit = 0.41 ± 0.55, observed = 0.43 ± 0.12, N = 6 OFF, p = 0.7 and mean Gaussian fit = 0.65 ± 0.035, observed = 0.75 ± 0.11, N = 7 ON, p = 0.04).

E. Cross-clustering of spine dynamics and mito remodeling ON dox is greater than chance. Histogram shows the distribution of spine permutations in 30,000 simulations of randomized new spine positions with respect to mito remodeling (mean Gaussian fit = 0.46 ± 0.24, observed = 0.24 ± 0.11, N = 6 OFF, p = 0.068 and mean Gaussian fit = 1.56 ± 0.17, observed = 0.6 ± 0.12, N = 7 ON, p < 0.0001).

F. Gain/loss of clustered dendritic spines ≤5 μm. Two-way ANOVA: dox x clustered dynamics F_1,22 = 26.07, p < 0.0001 post-hoc Tukey test: OFF vs ON groups **p < 0.0001, N = 6 OFF, 7 ON mice.

G. Gain/loss of mitochondrial coverage. Two-way ANOVA: dox x mitochondria remodeling F_1,22 = 19.92, p = 0.0002 post-hoc Tukey test: OFF vs ON groups *p < 0.0001, N = 6 OFF, 7 ON mice.

H. Effect of dox on the net change of mitochondria coverage and spine density. Student two-tailed T-test comparing OFF and ON dox groups for mito *p = 0.02 and spines *p = 0.002, N = 6 OFF and 7 ON dox mice.

I. Pearson correlation between mitochondria and spine changes in dendritic territories of N = 6 OFF, 7 ON mice.