(A) We measured hAR transgene expression in quadriceps muscle in male BAC fxAR121 – HSA-Cre bigenic mice in comparison to singly transgenic male BAC fxAR121 mice (n = 3 / group) by qRT-PCR analysis. We documented a marked reduction in hAR transgene expression in BAC fxAR121 – HSA-Cre mice at 12 weeks and 24 weeks of age. Transgene expression is given in arbitrary units, with BAC fxAR121 set to 1. **P < .01, ***P < .001, t-test.
(B) Western blot analysis of quadriceps muscle for 12 week-old male BAC fxAR121 – HSA-Cre bigenic mice and littermate male BAC fxAR121 mice indicates that hAR protein expression (arrowhead) is extremely reduced in muscle from BAC fxAR121 – HSA-Cre mice, when immunoblotted with anti-AR antibody, which cross-reacts with mAR protein (arrowhead). β-actin immunoblotting serves as a loading control.
(C) Densitometry quantification of muscle protein immunoblot data shown in (B), n = 4 separate experiments. ***P < .001, t-test.
(D) AR immunostaining of quadriceps muscle sections from 28 week-old male BAC fxAR121 mice, BAC fxAR121 – HSA-Cre mice, and non-transgenic littermate controls reveals a marked reduction in AR protein inclusions at the muscle cell periphery in BAC fxAR121 – HSA-Cre mice. Scale bar = 50 µm.
(E) We measured hAR transgene expression in spinal cord from 12 week-old male BAC fxAR121 – HSA-Cre bigenic mice and BAC fxAR121 mice (n = 3 / group) by qRT-PCR analysis, and observed similar hAR expression levels. P = n.s., t-test. Transgene expression is given in arbitrary units, with BAC fxAR121 set to 1.
(F) Western blot analysis of spinal cord for 12 week-old male BAC fxAR121 – HSA-Cre bigenic mice and littermate male BAC fxAR121 mice indicates that hAR protein expression (arrowhead) is not reduced, relative to mouse AR protein expression (arrowhead) in BAC fxAR121 – HSA-Cre mice, when immunoblotted with anti-AR antibody, which cross-reacts with mouse AR protein. β-actin immunoblotting serves as a loading control.
(G) Densitometry quantification of spinal cord protein immunoblot data shown in (F), n = 4 separate experiments. P = n.s., t-test. Error bars = s.e.m.