# kinase

/ˈkaɪˌneɪz/ (US) · /kˈɪneɪs/ (UK) · CEFR C2 · Noun

Source: https://englishreference.com/word/kinase
Updated: 2026-05-07

## Definition

a special protein in your body that acts like a switch to turn other proteins on or off. It does this by adding a tiny chemical group called a phosphate to them.

For teachers: an enzyme that catalyses the transfer of a phosphate group from a high-energy donor molecule, such as ATP, to a specific substrate. This process, known as phosphorylation, is a fundamental mechanism for regulating protein activity and cell signalling.

## Examples

- The kinase helps the cell respond to new signals.
- Researchers are developing new drugs that block a specific kinase to stop cancer cells from growing.
- By phosphorylating target proteins, the kinase acts as a critical molecular switch within the signalling pathway, effectively modulating the cell's metabolic response to external stimuli.

## Usage notes

- Commonly used in biochemistry and molecular biology; often named after the specific substrate it modifies.

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