repressor
Americannoun
-
Genetics. a protein that binds DNA at an operator site and thereby prevents transcription of one or more adjacent genes.
noun
Etymology
Origin of repressor
From Latin, dating back to 1955–60; see origin at repress, -tor
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
If lactose is present, the repressor protein does not bind to its operator.
From Textbooks • Jun. 9, 2022
What would be the result of a mutation in the repressor protein that prevented it from binding lactose?
From Textbooks • Jun. 9, 2022
If lactose is absent, then the repressor binds to the operator to prevent transcription.
From Textbooks • Jun. 9, 2022
When tryptophan is present in the cell, two tryptophan molecules bind to the trp repressor, which changes shape to bind to the trp operator.
From Textbooks • Jun. 9, 2022
Another repressor, from a virus, was isolated by Mark Ptashne and Nancy Hopkins in 1966.
From "The Gene" by Siddhartha Mukherjee
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Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.