Proteomic and Functional Studies Reveal Detyrosinated Tubulin as Treatment Target in Sarcomere Mutation-Induced Hypertrophic Cardiomyopathy

Maike Schuldt, Jiayi Pei, Magdalena Harakalova, Larissa M. Dorsch, Saskia Schlossarek, Michal Mokry, Jaco C. Knol, Thang V. Pham, Tim Schelfhorst, Sander R. Piersma, Cris Dos Remedios, Michiel Dalinghaus, Michelle Michels, Folkert W. Asselbergs, Marie-Jo Moutin, Lucie Carrier, Connie R. Jimenez, Jolanda van der Velden, Diederik W. D. Kuster

Research output: Contribution to journalArticleAcademicpeer-review


BACKGROUND: Hypertrophic cardiomyopathy (HCM) is the most common genetic heart disease. While ≈50% of patients with HCM carry a sarcomere gene mutation (sarcomere mutation-positive, HCMSMP), the genetic background is unknown in the other half of the patients (sarcomere mutation-negative, HCMSMN). Genotype-specific differences have been reported in cardiac function. Moreover, HCMSMN patients have later disease onset and a better prognosis than HCMSMP patients. To define if genotype-specific derailments at the protein level may explain the heterogeneity in disease development, we performed a proteomic analysis in cardiac tissue from a clinically well-phenotyped HCM patient group. METHODS: A proteomics screen was performed in cardiac tissue from 39 HCMSMP patients, 11HCMSMN patients, and 8 nonfailing controls. Patients with HCM had obstructive cardiomyopathy with left ventricular outflow tract obstruction and diastolic dysfunction. A novel MYBPC32373insG mouse model was used to confirm functional relevance of our proteomic findings. RESULTS: In all HCM patient samples, we found lower levels of metabolic pathway proteins and higher levels of extracellular matrix proteins. Levels of total and detyrosinated α-tubulin were markedly higher in HCMSMP than in HCMSMN and controls. Higher tubulin detyrosination was also found in 2 unrelated MYBPC3 mouse models and its inhibition with parthenolide normalized contraction and relaxation time of isolated cardiomyocytes. CONCLUSIONS: Our findings indicate that microtubules and especially its detyrosination contribute to the pathomechanism of patients with HCMSMP. This is of clinical importance since it represents a potential treatment target to improve cardiac function in patients with HCMSMP, whereas a beneficial effect may be limited in patients with HCMSMN.
Original languageEnglish
Article numbere007022
JournalCirculation. Heart failure
Issue number1
Publication statusPublished - 1 Jan 2021

Cite this