Fig. 1
The miRNA environment of the neonatal (PN2) hypothalamus is sexually dimorphic and dynamically responsive to estrogen. a OPLS-DA score plot of a model generated from the expression of 1407 miRNAs in the PN2 hypothalamus shows clear separation between control female (F/Veh) and male (M/Veh) groups along the predictive component (sex) (x-axis: R 2 = 0.45, Q 2 = 0.43, p[CV-ANOVA] = 0.04). b Volcano plot based on this multivariate model demonstrates that a clear majority of miRNAs was downregulated in M/Veh relative to F/Veh. F/Veh, (n = 5); M/Veh, (n = 6).c OPLS-DA score plot of a model generated from the expression of 162 miRNAs with a significant sex-bias (FDR ≤ 0.05) in the PN2 hypothalamus following a single PN1 injection of the aromatase inhibitor, formestane (20 μg) (Form), or vehicle (Veh) shows clear separation between F/Veh, control male M/Veh, and M/Form groups along the predictive component (treatment group) (x-axis: R 2 = 0.57, Q 2 = 0.39, p[CV-ANOVA] = 0.06). The F/Veh group is clustered around one central component, while the M/Form group is a distinct intermediary between F/Veh and M/Veh groups. d A plot of the mean M/Form expression of individual sex-biased miRNAs (y-axis) along a continuum between mean F/Veh and M/Veh expression (x-axis) [M/Form expression on continuum = (M/Form−F/Veh)/(M/Veh−F/Veh)]. While the magnitude of the basal sex difference varied between miRNAs, M/Form expression of 92 of these miRNAs was closer to F/Veh than M/Veh, suggesting that the sex-biased expression of these miRNAs is dependent on estrogen (red dots). e Seventy-one of these estrogen-responsive miRNAs were reduced in the M/Veh group relative to F/Veh. This suggests they are downregulated by estrogen. F/Veh, (n = 5); M/Veh, (n = 6), M/Form, (n = 7)