Related Experiment Video
Updated: Aug 8, 2026
09:29
Skeletal Muscle Gender Dimorphism from Proteomics
Published on: December 14, 2011
Summary
Altering chick hindlimb bone structure experimentally revealed that skeletal changes influence muscle development. This finding highlights the role of epigenetics in evolution and ancestral trait re-establishment.
Area of Science:
- Developmental Biology
- Evolutionary Biology
- Comparative Anatomy
Background:
- Skeletal and muscle systems develop in close coordination.
- Understanding the interplay between skeletal structure and muscle morphogenesis is crucial for developmental and evolutionary studies.
Purpose of the Study:
- To investigate the influence of skeletal elements on muscle development using an experimental approach.
- To compare experimentally induced skeletal changes with natural variation in extant and ancestral species.
Main Methods:
- Experimental surgery on chick hindlimbs (HH stage 23) to enlarge the fibula.
- Comparative analysis of resulting muscle alterations with musculature in other birds and reptiles.
Main Results:
- Induced skeletal changes led to secondary alterations in developing zeugopod muscles.
- Observed muscle patterns mirrored interspecific variation and ancestral arrangements, not random changes.
- Skeletal influence on muscle morphogenesis is proposed to be most effective during specific developmental phases (Phase 3).
Conclusions:
- Skeletal elements significantly influence muscle morphogenesis during a critical developmental window.
- Recreating ancestral epigenetic conditions can restore ancestral traits, suggesting a key role for epigenetic modifications in evolution.
Related Concept Videos
01:13Formation of Muscle Fibers from Myoblasts
De novo myogenesis, or the formation of muscle fibers, begins during the early embryonic stages. The skeletal muscle is formed from somites– blocks of embryonic cell layers. The somites are further divided into dermatomes, myotomes, sclerotomes, and syndetomes. Among these, the myotomes give rise to muscle fibers.
Muscle progenitor cells (MPCs) are formed from the myotomes. MPCs express genes that encode the transcription factors Pax3 and Pax7. Along with Pax 3/7, other transcription factors...
Muscle progenitor cells (MPCs) are formed from the myotomes. MPCs express genes that encode the transcription factors Pax3 and Pax7. Along with Pax 3/7, other transcription factors...
01:29Bone Formation by Intramembranous Ossification
Intramembranous ossification is one of the two processes involved in the development of bones within an embryo. The flat bones of the face, most of the cranial bones, and the clavicles are formed via this process. During intramembranous ossification, the bones develop directly from sheets of undifferentiated mesenchymal connective tissue.
The process begins when mesenchymal cells in the embryonic skeleton gather together and differentiate into osteogenic cells, which then develop into...
The process begins when mesenchymal cells in the embryonic skeleton gather together and differentiate into osteogenic cells, which then develop into...
01:09Changes in the Appendicular Skeleton with Age
The upper and lower limb initially develops as a small bulge called a limb bud, which appears on the lateral side of the early embryo. The upper limb bud appears near the end of the fourth week of development, with the lower limb bud appearing shortly after.
Initially, the limb buds consist of a core of mesenchyme covered by a layer of ectoderm. The ectoderm at the end of the limb bud thickens to form a narrow crest called the apical ectodermal ridge. This ridge stimulates the underlying...
Initially, the limb buds consist of a core of mesenchyme covered by a layer of ectoderm. The ectoderm at the end of the limb bud thickens to form a narrow crest called the apical ectodermal ridge. This ridge stimulates the underlying...
01:28Disorders of the Skeletal Muscle
The clinical conditions affecting the skeletal muscle tissue are broadly categorized as musculoskeletal and neuromuscular disorders.
Musculoskeletal disorders
Musculoskeletal disorders involve injuries and conditions affecting the skeletal muscles and associated connective tissues. These disorders can arise from acute biomechanical stresses or chronic overuse and can occur across different age groups. Common injuries include sprains, fractures, and muscular strains, often resulting from...
Musculoskeletal disorders
Musculoskeletal disorders involve injuries and conditions affecting the skeletal muscles and associated connective tissues. These disorders can arise from acute biomechanical stresses or chronic overuse and can occur across different age groups. Common injuries include sprains, fractures, and muscular strains, often resulting from...
01:25Fascicle Arrangement in Skeletal Muscles
Fascicles are bundles of muscle fibers in a skeletal muscle. Muscle fascicle arrangement is directly associated with the power and range of motion of various muscles. The configuration of these fascicles can vary, leading to different functional outcomes.
The four primary types of muscle based on fascicle arrangement are:
The four primary types of muscle based on fascicle arrangement are:
01:12Alterations in Muscle Tone ll
Alterations in muscle tone are common manifestations of neurological disorders and reflect dysfunction within different nervous system regions. Spasticity, paratonia, and dystonia represent distinct forms of hypertonia, each with unique mechanisms, clinical features, and diagnostic importance.CharacteristicsSpasticity happens from upper motor neuron lesions and is characterized by velocity-dependent resistance to passive movement. Clinical features include:Exaggerated deep tendon reflexesClonus...