Desmin

Desmin (DES) is a muscle-specific type III intermediate filament protein (UniProt: P17661) essential for muscular structure and function. It maintains sarcomeric organization by interconnecting Z-disks and myofibrils, and anchors them to the sarcolemmal cytoskeleton, nucleus, and mitochondria, providing mechanical strength during muscle contraction. Desmin also contributes to nuclear membrane integrity and may regulate transcription of cardiogenic genes during myogenesis.

Desmin is primarily expressed in striated and cardiac muscle tissues. Mutations in DES cause myofibrillar myopathies and cardiomyopathies, including myofibrillar myopathy type 1 (MFM1), dilated cardiomyopathy (CMD1I), and Kaeser syndrome, characterized by progressive weakness, cardiac arrhythmias, and desmin-reactive accumulation in muscle cells (UniProt: P17661).

In Alzheimer's disease, desmin is upregulated in post-mortem AD brain tissue compared to age-matched controls (Chaparral AD proteomics), with a mean log2 fold-change of 1.044. This upregulation was detected across the analyzed subcellular fractions in a TMT-labeled proteomic study, suggesting potential involvement in AD-associated pathology, though the mechanistic significance in neuronal and non-neuronal cells of the brain remains to be elucidated.