ubiquitin

American  

[yoo-bik-wi-tin] / juˈbɪk wɪ tɪn /

noun

1. a small protein, present in all eukaryotic cells, that participates in the destruction of defective proteins and in the synthesis of new proteins.

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ubiquitin British  

/ juːˈbɪkwɪtɪn /

noun

1. biochem a small polypeptide, found in most eukaryotic cells, that combines with other proteins to make them susceptible to degradation

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Other Word Forms

• ubiquitination
  noun

Etymology

Origin of ubiquitin

First recorded in 1985–90; ubiquit(ous) + -in ¹

Example Sentences

See Examples For:

ubiquitin

Their experiments revealed that UNI418 activates a protein disposal pathway called the Cul4A ubiquitin ligase complex.

From Science Daily ● Jun. 10, 2026

This vital task falls upon specialized enzymes known as ubiquitin ligases, which tag obsolete proteins for degradation, guiding them to the cellular recycling center, the proteasome.

From Science Daily ● Feb. 21, 2024

This form of ubiquitin helps cells communicate by sending a molecular message -- communication that remains poorly understood.

From Science Daily ● Dec. 12, 2023

The study details the steps taken to create a form of the protein known as lysine 6 polyubiquitin, where a long chain of ubiquitin molecules are linked through the amino acid lysine.

From Science Daily ● Dec. 12, 2023

Usually in plants, in fact across all multicellular organisms, this recycling of proteins in the proteasome is dependent on a molecule called ubiquitin.

From Science Daily ● Dec. 5, 2023