Expression of an alpha cardiac-like myosin heavy chain in muscle spindle fibres

1990 ◽  
Vol 95 (2) ◽  
pp. 105-113 ◽  
Author(s):  
F. Pedrosa ◽  
T. Soukup ◽  
L. -E. Thornell
Keyword(s):  
Myosin Heavy Chain ◽  
Muscle Spindle ◽  
Heavy Chain ◽  
Spindle Fibres

scholarly journals Fiber Content and Myosin Heavy Chain Composition of Muscle Spindles in Aged Human Biceps Brachii

2005 ◽  
Vol 53 (4) ◽  
pp. 445-454 ◽  
Author(s):  
Jing-Xia Liu ◽  
Per-Olof Eriksson ◽  
Lars-Eric Thornell ◽  
Fatima Pedrosa-Domellöf
Keyword(s):  
Myosin Heavy Chain ◽  
Muscle Spindle ◽  
Heavy Chain ◽  
Biceps Brachii ◽  
Fiber Type ◽  
Muscle Spindles ◽  
The Elderly ◽  
Age Related ◽  
Nuclear Chain ◽  
Slow Myhc

The present study investigated potential age-related changes in human muscle spindles with respect to the intrafusal fiber-type content and myosin heavy chain (MyHC) composition in biceps brachii muscle. The total number of intrafusal fibers per spindle decreased significantly with aging, due to a significant reduction in the number of nuclear chain fibers. Nuclear chain fibers in old spindles were short and some showed novel expression of MyHC α-cardiac. The expression of MyHC α-cardiac in bag1 and bag2 fibers was greatly decreased in the A region. The expression of slow MyHC was increased in nuclear bag1 fibers and that of fetal MyHC decreased in bag2 fibers whereas the patterns of distribution of the remaining MyHC isoforms were generally not affected by aging. We conclude that aging appears to have an important impact on muscle spindle composition. These changes in muscle spindle phenotype may reflect an age-related deterioration in sensory and motor innervation and are likely to have an impact in motor control in the elderly.

scholarly journals A screen for genetic loci required for body-wall muscle development during embryogenesis in Caenorhabditis elegans.

Genetics ◽  
1994 ◽  
Vol 137 (2) ◽  
pp. 483-498
Author(s):  
J Ahnn ◽  
A Fire
Keyword(s):  
Caenorhabditis Elegans ◽  
Myosin Heavy Chain ◽  
Muscle Cell ◽  
Heavy Chain ◽  
Body Wall ◽  
Muscle Development ◽  
Contractile Function ◽  
The Body ◽  
Body Wall Muscle ◽  
Genetic Loci

Abstract We have used available chromosomal deficiencies to screen for genetic loci whose zygotic expression is required for formation of body-wall muscle cells during embryogenesis in Caenorhabditis elegans. To test for muscle cell differentiation we have assayed for both contractile function and the expression of muscle-specific structural proteins. Monoclonal antibodies directed against two myosin heavy chain isoforms, the products of the unc-54 and myo-3 genes, were used to detect body-wall muscle differentiation. We have screened 77 deficiencies, covering approximately 72% of the genome. Deficiency homozygotes in most cases stain with antibodies to the body-wall muscle myosins and in many cases muscle contractile function is observed. We have identified two regions showing distinct defects in myosin heavy chain gene expression. Embryos homozygous for deficiencies removing the left tip of chromosome V fail to accumulate the myo-3 and unc-54 products, but express antigens characteristic of hypodermal, pharyngeal and neural development. Embryos lacking a large region on chromosome III accumulate the unc-54 product but not the myo-3 product. We conclude that there exist only a small number of loci whose zygotic expression is uniquely required for adoption of a muscle cell fate.

Sign in / Sign up

Export Citation Format

Share Document