Muscle protein degradation aging cells

Maturation or aging is accompanied by morphological changes which primarily affect the cytoskeleton. Microexaminations show that the Z lines, which as cross structures (cf. 12.2.1) separate the individual sarcomeres in the muscle fibril, are broken up during aging. In addition, the fibrillar proteins titin and desmin are degraded. In comparison, the contractile proteins myosin and actin are stable. They are attacked only at temperatures above 25 °C. The connective tissue present outside the muscle cells also remains intact. 

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