- Regulator gene
A regulator gene or regulatory gene is a
gene involved in controlling the expression of one or more other genes. A regulator gene may encode a protein, or it may work at the level ofRNA , as in the case of genes encodingmicroRNA s.In
prokaryotes , regulator genes often code forrepressor protein s. Repressor proteins bind to operators orpromoter s, preventingRNA polymerase from transcribing RNA.Inducer s cause repressor proteins to change shape or otherwise become unable to bind DNA, allowing RNA polymerase to continue transcription.Other regulatory genes code for
activator protein s. An activator binds to a site on the DNA molecule and causes an increase in transcription of a nearby gene. In prokaryotes, a well-known example of an activator protein is thecatabolite activator protein or CAP, which is involved inpositive control of thelac operon .In
eukaryotic gene regulation both activators and repressors are known to play important roles. [ Griffiths AJF, Wessler SR, Lewontin RC, Gelbart WM, Suzuki DT, Miller JH. Introduction to Genetic Analysis, 8th ed. New York: W.H. Freeman and Co., 2005.]External links
*
References
Wikimedia Foundation. 2010.