2024-03-29T07:11:10Zhttp://repisalud.isciii.es/oai/requestoai:repisalud.isciii.es:20.500.12105/137102023-07-11T00:01:11Zcom_20.500.12105_2145com_20.500.12105_2051com_20.500.12105_2144col_20.500.12105_2151
00925njm 22002777a 4500
dc
Cancemi, Andrea
author
2021-11-19
Calcium transients between the Sarcoplasmic Reticulum (SR) and the cytoplasm are essential for coordinated contraction in cardiomyocytes. Loss of the SR protein Calsequestrin 2 (CASQ2) causes the recessive form of Catecholaminergic Polymorphic Ventricular Tachycardia (CPVT2) by increasing the diastolic opening probability of the main SR calcium channel Ryanodine receptor 2 (RyR2), and by causing an unexplained decrease of its regulatory protein Triadin (TRDN). Here we studied the mechanisms of TRDN reduction in CASQ2-KO mice and show that ablation of CASQ2 activates histone-deacetylase HDAC6, which regulates several cellular processes. In CASQ2 deficient cardiomyocytes, HDAC6 reduces alpha-Tubulin acetylation, thus impairing microtubule stability and altering TRDN trafficking and co-localization with RyR2. Misplaced TRDN binds HSP70, forming Aggresomes that are degraded by autophagy. The study identifies a novel cascade of post-transcriptional events initiated by the loss of CASQ2 that leads to a major rearrangement of SR protein trafficking and stability in cardiomyocytes
http://hdl.handle.net/20.500.12105/13710
10.4321/repisalud.13710
inherited arrhythmias
CpvT
Microtubulus
autophagy
Cytoskeletal remodeling and enhanced autophagy drive an adaptive response to loss of Calsequestrin in a model of inherited arrhythmias