Heavy long-term ethanol consumption induces an alpha- to beta-myosin heavy chain isoform transition in rat

1999 ◽  
Vol 94 (6) ◽  
pp. 481-488 ◽  
Author(s):  
Julia Meehan ◽  
Mariann R. Piano ◽  
R. John Solaro ◽  
John M. Kennedy
Keyword(s):  
Myosin Heavy Chain ◽  
Heavy Chain ◽  
Ethanol Consumption ◽  
Myosin Heavy Chain Isoform

Myosin heavy chain isoform mRNA and protein levels after long-term paralysis

2004 ◽  
Vol 325 (1) ◽  
pp. 296-301 ◽  
Author(s):  
Robert J. Talmadge ◽  
Nicole D. Garcia ◽  
Roland R. Roy ◽  
V. Reggie Edgerton
Keyword(s):  
Myosin Heavy Chain ◽  
Heavy Chain ◽  
Myosin Heavy Chain Isoform ◽  
Protein Levels

scholarly journals The Drosophila indirect flight muscle myosin heavy chain isoform is insufficient to transform the jump muscle into a highly stretch-activated muscle type

2017 ◽  
Vol 312 (2) ◽  
pp. C111-C118 ◽  
Author(s):  
Cuiping Zhao ◽  
Douglas M. Swank
Keyword(s):  
Power Generation ◽  
Myosin Heavy Chain ◽  
Heavy Chain ◽  
Flight Muscle ◽  
Fold Increase ◽  
Isometric Tension ◽  
Indirect Flight Muscle ◽  
Muscle Type ◽  
Myosin Heavy Chain Isoform ◽  
Muscle Types

Stretch activation (SA) is a delayed increase in force that enables high power and efficiency from a cyclically contracting muscle. SA exists in various degrees in almost all muscle types. In Drosophila, the indirect flight muscle (IFM) displays exceptionally high SA force production ( FSA), whereas the jump muscle produces only minimal FSA. We previously found that expressing an embryonic (EMB) myosin heavy chain (MHC) isoform in the jump muscle transforms it into a moderately SA muscle type and enables positive cyclical power generation. To investigate whether variation in MHC isoforms is sufficient to produce even higher FSA, we substituted the IFM MHC isoform (IFI) into the jump muscle. Surprisingly, we found that IFI only caused a 1.7-fold increase in FSA, less than half the increase previously observed with EMB, and only at a high Pi concentration, 16 mM. This IFI-induced FSA is much less than what occurs in IFM, relative to isometric tension, and did not enable positive cyclical power generation by the jump muscle. Both isometric tension and FSA of control fibers decreased with increasing Pi concentration. However, for IFI-expressing fibers, only isometric tension decreased. The rate of FSA generation was ~1.5-fold faster for IFI fibers than control fibers, and both rates were Pi dependent. We conclude that MHC isoforms can alter FSA and hence cyclical power generation but that isoforms can only endow a muscle type with moderate FSA. Highly SA muscle types, such as IFM, likely use a different or additional mechanism.

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