Integration of Cardiac Actin Mutants Causing Hypertrophic (p.A295S) and Dilated Cardiomyopathy (p.R312H and p.E361G) into Cellular Structures - Archive ouverte HAL Access content directly
Journal Articles Antioxidants Year : 2021

Integration of Cardiac Actin Mutants Causing Hypertrophic (p.A295S) and Dilated Cardiomyopathy (p.R312H and p.E361G) into Cellular Structures

, , , , (1, 2) , , , , , ,
1
2
Constanze Erdmann
  • Function : Author
Roua Hassoun
  • Function : Author
Sebastian Schmitt
  • Function : Author
Carlos Kikuti
Antonina Mazur
Andreas Mügge
  • Function : Author
Nazha Hamdani
  • Function : Author
Matthias Geyer
Kornelia Jaquet
  • Function : Author
Hans Georg Mannherz
  • Function : Author

Abstract

The human mutant cardiac α-actins p.A295S or p.R312H and p.E361G, correlated with hypertrophic or dilated cardiomyopathy, respectively, were expressed by the baculovirus/Sf21 insect cell system and purified to homogeneity. The purified cardiac actins maintained their native state but showed differences in Ca2+-sensitivity to stimulate the myosin-subfragment1 ATPase. Here we analyzed the interactions of these c-actins with actin-binding and -modifying proteins implicated in cardiomyocyte differentiation. We demonstrate that Arp2/3 complex and the formin mDia3 stimulated the polymerization rate and extent of the c-actins, albeit to different degrees. In addition, we tested the effect of the MICAL-1 monooxygenase, which modifies the supramolecular actin organization during development and adaptive processes. MICAL-1 oxidized these c-actin variants and induced their de-polymerization, albeit at different rates. Transfection experiments using MDCK cells demonstrated the preferable incorporation of wild type and p.A295S c-actins into their microfilament system but of p.R312H and p.E361G actins into the submembranous actin network. Transduction of neonatal rat cardiomyocytes with adenoviral constructs coding HA-tagged c-actin variants showed their incorporation into microfilaments after one day in culture and thereafter into thin filaments of nascent sarcomeric structures at their plus ends (Z-lines) except the p.E361G mutant, which preferentially incorporated at the minus ends.

Dates and versions

Identifiers

Cite

Constanze Erdmann, Roua Hassoun, Sebastian Schmitt, Carlos Kikuti, Anne Houdusse, et al.. Integration of Cardiac Actin Mutants Causing Hypertrophic (p.A295S) and Dilated Cardiomyopathy (p.R312H and p.E361G) into Cellular Structures. Antioxidants , 2021, 10 (7), pp.1082. ⟨10.3390/antiox10071082⟩. ⟨hal-03453111⟩
9 View
0 Download

Altmetric

Share

Gmail Facebook Twitter LinkedIn More