A Scoping Review of Sarcoglycan Expression in Non-Muscle Organs: Beyond Muscles

Area of Science:

• Biochemistry
• Cell Biology
• Neuroscience

Background:

• Sarcoglycans (SGs) are a family of transmembrane proteins.
• Traditionally, SGs were considered exclusively expressed in skeletal and cardiac muscle.
• Their precise roles in non-muscle tissues remained largely unexplored.

Purpose of the Study:

• To conduct a scoping review on sarcoglycan expression and molecular features in non-muscle organs.
• To challenge the established dogma of SG function being limited to muscle tissues.
• To identify potential novel functions and implications of SGs in diverse physiological and pathological contexts.

Main Methods:

• Scoping review methodology.
• Analysis of existing literature from animal models and human studies.
• Examination of expression patterns and molecular characteristics of SG subunits.

Main Results:

• Sarcoglycans are widely expressed in various non-muscle organs, including the nervous system, glands, adipose tissue, oral mucosa, and retina.
• Distinct regional and cell-type-specific expression patterns were observed.
• Evidence suggests roles in synaptic organization, neurotransmission, cellular integrity, and homeostasis in non-muscle tissues.
• Altered SG expression is linked to pathological conditions, such as in the oral mucosa.

Conclusions:

• Sarcoglycans possess multifaceted roles beyond muscle, contributing to cellular signaling, membrane stability, and neurovascular coupling.
• Significant knowledge gaps exist regarding SG post-translational modifications and functional significance in non-muscle tissues.
• Further research is crucial to fully elucidate SG functions and explore their therapeutic potential in non-muscle related diseases.