Non-linear myofilament elasticity in frog intact muscle fibres.

Supplementary Information Significant Impact on Muscle Mechanics of Small Non-linearities in Myofilament Elasticity

There is no experimental evidence for non-linear myofilament elasticity in skeletal muscle.

Information on the stiffness of the actin and myosin filaments is a key parameter in the study of muscle contraction. For example, the number of motors attached to actin in each half-sarcomere of a muscle fibre can be obtained from measurements of the half-sarcomere stiffness, provided that the compliances of the actin and myosin filaments are known (Piazzesi et al., 2007). The stress–strain re...

Mechanics of myosin function in white muscle fibres of the dogfish, Scyliorhinus canicula

The contractile properties of muscle fibres have been extensively investigated by fast perturbation in sarcomere length to define the mechanical characteristics of myofilaments and myosin heads that underpin refined models of the acto-myosin cycle. Comparison of published data from intact fast-twitch fibres of frog muscle and demembranated fibres from fast muscle of rabbit shows that stiffness ...

Biochemical comparison of fast- and slow-contracting squid muscle.

The myofilament protein compositions of muscle fibres from the transverse muscle mass of the tentacles and the transverse muscle mass of the arms of the loliginid squid Sepioteuthis lessoniana were compared. These two muscle masses are distinct types, differing in their ultrastructural and behavioural properties. The transverse muscle of the tentacles consists of specialized muscle fibres that ...

Studies on the fine structure of muscle fibres and contained crystalloids in basal socket muscle of the entoproct, Barentsia gracilis.

Basal socket muscle fibres of Barentsia gracilis are morphologically similar to invertebrate muscles classified as slow, tonic-type muscles. They are divisible into a non-contractile bulbous and a contractile myofilamentous portion, are innervated on their non-contractile surface, and are obliquely striated. The electron density and myofilament packing vary from fibre to fibre. Some muscle fibr...