| First Author | Dutsch A | Year | 2019 |
| Journal | Sci Rep | Volume | 9 |
| Issue | 1 | Pages | 18152 |
| PubMed ID | 31796859 | Mgi Jnum | J:287323 |
| Mgi Id | MGI:6405812 | Doi | 10.1038/s41598-019-54665-2 |
| Citation | Dutsch A, et al. (2019) Phosphomimetic cardiac myosin-binding protein C partially rescues a cardiomyopathy phenotype in murine engineered heart tissue. Sci Rep 9(1):18152 |
| abstractText | Phosphorylation of cardiac myosin-binding protein C (cMyBP-C), encoded by MYBPC3, increases the availability of myosin heads for interaction with actin thus enhancing contraction. cMyBP-C phosphorylation level is lower in septal myectomies of patients with hypertrophic cardiomyopathy (HCM) than in non-failing hearts. Here we compared the effect of phosphomimetic (D282) and wild-type (S282) cMyBP-C gene transfer on the HCM phenotype of engineered heart tissues (EHTs) generated from a mouse model carrying a Mybpc3 mutation (KI). KI EHTs showed lower levels of mutant Mybpc3 mRNA and protein, and altered gene expression compared with wild-type (WT) EHTs. Furthermore, KI EHTs exhibited faster spontaneous contractions and higher maximal force and sensitivity to external [Ca(2+)] under pacing. Adeno-associated virus-mediated gene transfer of D282 and S282 similarly restored Mybpc3 mRNA and protein levels and suppressed mutant Mybpc3 transcripts. Moreover, both exogenous cMyBP-C proteins were properly incorporated in the sarcomere. KI EHTs hypercontractility was similarly prevented by both treatments, but S282 had a stronger effect than D282 to normalize the force-Ca(2+)-relationship and the expression of dysregulated genes. These findings in an in vitro model indicate that S282 is a better choice than D282 to restore the HCM EHT phenotype. To which extent the results apply to human HCM remains to be seen. |