ArticlePloS one2012
Role of alpha-actinin-3 in contractile properties of human single muscle fibers: a case series study in paraplegics.
Article in PloS one, 2012. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 22 papers.
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
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Who cites it
22 citing papers in PubMed, 47 citations in OpenAlex.
- Muscle Work and Its Relationship withGenes · 2021Trial
- Optimizing the methodology for precise estimation of skeletal muscle fiber type proportions in humans.Scientific reports · 2025Article
- Global trends in scientific production on physical exercise and spinal cord injury.Frontiers in sports and active living · 2025Review
- Impact of ACTN3 R577X Polymorphism on Muscle Damage Susceptibility Following Aerobic or Strength Exercises: A Systematic Review.International journal of preventive medicine · 2025Review
- Association between ComplexGenes · 2024Article
- Genetic profile of sports climbing athletes from three different ethnicities.Biology of sport · 2022Article
- Genetics and sports performance: the present and future in the identification of talent for sports based on DNA testing.European journal of applied physiology · 2022Review
- Association of Genetic Variances inSports (Basel, Switzerland) · 2021Article
- Pathophysiology of exercise-induced muscle damage and its structural, functional, metabolic, and clinical consequences.Physiological research · 2020Review
- Genetics of Muscle Stiffness, Muscle Elasticity and Explosive Strength.Journal of human kinetics · 2020Article
- Fiber typing human skeletal muscle with fluorescent immunohistochemistry.Journal of applied physiology (Bethesda, Md. : 1985) · 2019Review
- Association ofInternational journal of environmental research and public health · 2019Article
- Genetic variation and exercise-induced muscle damage: implications for athletic performance, injury and ageing.European journal of applied physiology · 2016Review
- Improving human skeletal muscle myosin heavy chain fiber typing efficiency.Journal of muscle research and cell motility · 2016Article
- Association of ACTN3 R577X but not ACE I/D gene variants with elite rugby union player status and playing position.Physiological genomics · 2016Article
- Rodent models for resolving extremes of exercise and health.Physiological genomics · 2016Review
- Article
- Effective utilization of genetic information for athletes and coaches: focus on ACTN3 R577X polymorphism.Journal of exercise nutrition & biochemistry · 2015Review
- History-dependent force, angular velocity and muscular endurance in ACTN3 genotypes.European journal of applied physiology · 2015Article
- Association of the ACTN3 R577X polymorphism with glucose tolerance and gene expression of sarcomeric proteins in human skeletal muscle.Physiological reports · 2015Article
Corrections and comments
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Authors and funding
6 authors at 2 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
A common nonsense polymorphism in the ACTN3 gene results in the absence of α-actinin-3 in XX individuals. The wild type allele has been associated with power athlete status and an increased force output in numeral studies, though the mechanisms by which these effects occur are unclear. Recent findings in the Actn3(-/-) (KO) mouse suggest a shift towards 'slow' metabolic and contractile characteristics of fast muscle fibers lacking α-actinin-3. Skinned single fibers from the quadriceps muscle of three men with spinal cord injury (SCI) were tested regarding peak force, unloaded shortening velocity, force-velocity relationship, passive tension and calcium sensitivity. The SCI condition induces an 'equal environment condition' what makes these subjects ideal to study the role of α-actinin-3 on fiber type expression and single muscle fiber contractile properties. Genotyping for ACTN3 revealed that the three subjects were XX, RX and RR carriers, respectively. The XX carrier's biopsy was the only one that presented type I fibers with a complete lack of type II(x) fibers. Properties of hybrid type II(a)/II(x) fibers were compared between the three subjects. Absence of α-actinin-3 resulted in less stiff type II(a)/II(x) fibers. The heterozygote (RX) exhibited the highest fiber diameter (0.121±0.005 mm) and CSA (0.012±0.001 mm(2)) and, as a consequence, the highest peak force (2.11±0.14 mN). Normalized peak force was similar in all three subjects (P = 0.75). Unloaded shortening velocity was highest in R-allele carriers (P<0.001). No difference was found in calcium sensitivity. The preservation of type I fibers and the absence of type II(x) fibers in the XX individual indicate a restricted transformation of the muscle fiber composition to type II fibers in response to long-term muscle disuse. Lack of α-actinin-3 may decrease unloaded shortening velocity and increase fiber elasticity.
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