Defective proteins are degraded after attaching covalently to -
Ans. is 'd' i.e., Ubiquitin o Defective proteins are often marked for destruction by ubiquitination (attachment of small, highly conserved protein called ubiquitin). Such proteins are rapidly degraded by proteosome, which is a macromolecular, ATP dependent, proteolytic system located in the cytosol.
Clathrin
Pepsin
Laminin
Ubiquitin
Biological Function of Proteins