Phenotype-specific muscle proteomic profiling in titinopathies.

Area of Science:

• Neuromuscular Disorders
• Molecular Biology
• Genetics

Background:

• Titinopathies are complex neuromuscular disorders with diverse phenotypes, stemming from the large size of the titin gene and protein.
• Understanding protein alterations is crucial for characterizing titinopathies, particularly arthrogryposis and myofibrillar myopathy phenotypes.

Purpose of the Study:

• To analyze and compare protein deregulations in French patients with arthrogryposis and myofibrillar myopathy phenotypes of titinopathies.
• To identify phenotype-specific protein changes and disrupted signaling networks in titinopathies.

Main Methods:

• Muscle biopsies from patients with titinopathies (arthrogryposis and myofibrillar myopathy phenotypes) and control individuals were analyzed.
• Mass spectrometry was employed to quantify protein level changes in the patient cohorts.

Main Results:

• Specific protein deregulations were identified for each phenotype: fibrosis and actomyosin complex involvement in arthrogryposis, and cytoskeleton-related muscle contraction system impact in myofibrillar myopathy.
• Quantitative proteomic analysis revealed disrupted signaling networks underlying titinopathies.

Conclusions:

• The study provides a detailed characterization of protein alterations in distinct titinopathy phenotypes.
• Findings support the identification of phenotype-specific biomarkers and may guide the development of targeted therapies for titinopathies.