What is the primary mechanism by which proteins are degraded in the cell, involving the tagging of proteins with a small protein called ubiquitin?

A Proteasomal degradation ✓
B Lysosomal degradation
C Autophagic degradation
D Exosomal degradation

Explanation

Proteasomal degradation is the primary mechanism by which proteins are degraded in the cell, involving the tagging of proteins with a small protein called ubiquitin, which marks them for destruction by the proteasome.

Mnemonic

Ubiquitin = 'ubiquitous' tag for destruction

Source

Alberts et al., Molecular Biology of the Cell
Protein Metabolism Biochemistry Protein Degradation Medium MEDICAL Confidence: high