protein degradation

chemistry

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Last updated

July 16, 2026

Quick Summary

Protein degradation, also known as proteolysis, is the process by which proteins are broken down into smaller peptides or amino acids by proteolytic enzymes. This occurs both in food digestion, primarily in the stomach and small intestine, and within cells as part of cellular maintenance.1

In living organisms, a key pathway for protein degradation involves a molecule called ubiquitin. Ubiquitin attaches to unwanted proteins, marking them for destruction by a proteasome, a complex of enzymes that breaks down the protein into amino acids. This ubiquitin-mediated process is crucial for controlling cell division, DNA repair, and gene transcription.2

Another form of cellular breakdown is autophagy, where organelles called lysosomes degrade worn or malfunctioning cellular components. Autophagy serves housekeeping functions, recycling cellular materials and balancing energy demands during stress. This process is vital for cellular health and is implicated in various diseases when it malfunctions.3

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Aaron J. Ciechanover
…Rose also demonstrated that ubiquitin-mediated protein degradation helps control a number of other critical biochemical processes, including cell division, the repair of defects in DNA, and gene transcription, the process in which genes use their coded instructions to manufacture a protein. Diseases such as cystic fibrosis result when the protein-degradation…
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…Rose also demonstrated that ubiquitin-mediated protein degradation helps control a number of other critical biochemical processes, including cell division, the repair of defects in DNA, and gene transcription, the process in which genes use their coded instructions to manufacture a protein. Diseases such as cystic fibrosis result when the protein-degradation…
Read More

Avram Hershko
…Rose also demonstrated that ubiquitin-mediated protein degradation helps control a number of other critical biochemical processes, including cell division, the repair of defects in DNA, and gene transcription, the process in which genes use their coded instructions to manufacture a protein. Diseases such as cystic fibrosis result when the protein-degradation…
Read More
…Rose also demonstrated that ubiquitin-mediated protein degradation helps control a number of other critical biochemical processes, including cell division, the repair of defects in DNA, and gene transcription, the process in which genes use their coded instructions to manufacture a protein. Diseases such as cystic fibrosis result when the protein-degradation…
Read More

Irwin Rose
…Hershko also demonstrated that ubiquitin-mediated protein degradation helps control a number of other critical biochemical processes, including cell division, the repair of defects in DNA, and gene transcription, the process in which genes use their coded instructions to manufacture a protein. Such diseases as cystic fibrosis result when the protein-degradation…
Read More
…Hershko also demonstrated that ubiquitin-mediated protein degradation helps control a number of other critical biochemical processes, including cell division, the repair of defects in DNA, and gene transcription, the process in which genes use their coded instructions to manufacture a protein. Such diseases as cystic fibrosis result when the protein-degradation…
Read More