Question #62d27

1 Answer
Nov 14, 2017

When there is Lactose around...

Explanation:

The LAC-operon is a combination of DNA-regions that together code for the enzymes needed for the breakdown of Lactose, as well as for the expression of these genes:

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Normally the genes (actually the whole region) is inactivated by a repressor. Lactose binds to this repressor, enabling the gene to by transcribed by RNA Polymerase...

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The lac operon. Top:Repressed, Bottom:Active.
1 : RNA Polymerase,
2 : Repressor,
3 : Promoter,
4 : Operator,
5 : Lactose,
6, 7, 8 : lacZ, lacY, lacA.

(pictures courtesy of https://en.wikipedia.org/wiki/Lac_operon)