Tropomyosin (Tm) is an essential component in the regulation of striated muscle contraction. Questions about Tm functional role have been difficult to study because sarcomere Tm content is not as easily manipulated as Troponin (Tn). Here we describe the method we recently developed to replace Tm-Tn of skeletal and cardiac myofibrils from animals and humans to generate an experimental model of homogeneous Tm composition and giving the possibility to measure a wide range of mechanical parameters of contraction (e.g. maximal force and kinetics of force generation). The success of the exchange was determined by SDS-PAGE and by mechanical measurements of calcium dependent force activation on the reconstituted myofibrils. In skeletal and cardiac myofibrils, the percentage of Tm replacement was higher than 90%. Maximal isometric tension was 30-35% lower in the reconstituted myofibrils than in control myofibrils but the rate of force activation (k(ACT)) and that of force redevelopment (k(TR)) were not significantly changed. Preliminary results show the effectiveness of Tm replacement in human cardiac myofibrils. This approach can be used to test the functional impact of Tm mutations responsible for human cardiomyopathies.

Extraction and Replacement of the Tropomyosin-Troponin Complex in Isolated Myofibrils / Beatrice, Scellini ; Nicoletta, Piroddi; Corrado, Poggesi; Chiara Tesi. - STAMPA. - (2010), pp. 163-174. [10.1007/978-1-4419-6366-6_9]

Extraction and Replacement of the Tropomyosin-Troponin Complex in Isolated Myofibrils.

SCELLINI, BEATRICE;PIRODDI, NICOLETTA;POGGESI, CORRADO;TESI, CHIARA
2010

Abstract

Tropomyosin (Tm) is an essential component in the regulation of striated muscle contraction. Questions about Tm functional role have been difficult to study because sarcomere Tm content is not as easily manipulated as Troponin (Tn). Here we describe the method we recently developed to replace Tm-Tn of skeletal and cardiac myofibrils from animals and humans to generate an experimental model of homogeneous Tm composition and giving the possibility to measure a wide range of mechanical parameters of contraction (e.g. maximal force and kinetics of force generation). The success of the exchange was determined by SDS-PAGE and by mechanical measurements of calcium dependent force activation on the reconstituted myofibrils. In skeletal and cardiac myofibrils, the percentage of Tm replacement was higher than 90%. Maximal isometric tension was 30-35% lower in the reconstituted myofibrils than in control myofibrils but the rate of force activation (k(ACT)) and that of force redevelopment (k(TR)) were not significantly changed. Preliminary results show the effectiveness of Tm replacement in human cardiac myofibrils. This approach can be used to test the functional impact of Tm mutations responsible for human cardiomyopathies.
2010
978-1-4419-6366-6
Muscle Biophysics
163
174
Beatrice, Scellini ; Nicoletta, Piroddi; Corrado, Poggesi; Chiara Tesi
File in questo prodotto:
File Dimensione Formato  
Scellini et al-dilson.pdf

Accesso chiuso

Tipologia: Altro
Licenza: Tutti i diritti riservati
Dimensione 1.67 MB
Formato Adobe PDF
1.67 MB Adobe PDF   Richiedi una copia

I documenti in FLORE sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificatore per citare o creare un link a questa risorsa: https://hdl.handle.net/2158/397963
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 7
  • ???jsp.display-item.citation.isi??? 7
social impact