SERCA2 Haploinsufficiency in a Mouse Model of Darier Disease Causes a Selective Predisposition to Heart Failure

Figure 6

Effects of Atp2a2 heterozygosity on regulators of Ca²⁺-handling and phosphatases in HCM models. Hearts from WT mice, mice expressing the Glu180Gly mutant -tropomyosin (HCM), and HCM/Atp2a2^+/− double mutant (HCM/HET) mice were processed for RT-PCR and immunoblots. RT-PCR analysis of mRNA for (a) SERCA2 (Atp2a2) and (b) phospholamban (Pln), (c) immunoblot analysis of SERCA2a and PLN, and (d) quantitation of SERCA2a protein. RT-PCR analyses of mRNA for (e) plasma membrane Ca²⁺-ATPase isoform 4 (Atp2b4), (f) plasma membrane Ca²⁺-ATPase isoform 1 (Atp2b1), (g) sarcolemmal calcium release-activated calcium modulator 1 (Orai1), and (h) stromal interaction molecule 1 (Stim1) and (i) immunoblot analyses of the catalytic subunits of calcineurin (CnA), protein phosphatase 1, (PP1-C), and protein phosphatase 2A (PP2A-C) in HCM and HCM/HET hearts. (j) Quantitation of PP1-C protein levels. RT-PCR analyses of mRNA for (k) regulator of calcineurin 1 (Rcan1) and (l) regulator of calcineurin 2 (Rcan2). mRNA levels were normalized to Gapdh and protein levels were normalized to sarcomeric actin (s.actin). Values are means ± SE. = at least 4 for each genotype. versus WT controls; versus HCM; versus WT controls.

(a)

(b)

(c)

(d)

(e)

(f)

(g)

(h)

(i)

(j)

(k)

(l)