G-pro·tein (jēprō′tēn′, -tē-ĭn)
Any of a class of cell membrane proteins that transmit signals from certain receptors to effector enzymes, enabling the cell to regulate its metabolism in response to hormones and other extracellular stimuli.
[From GTP-binding regulatory protein.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
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