1. Tardigrade
  2. Question
  3. Biology
  4. In E.coli, an operator gene combines with

Q. In E.coli, an operator gene combines with

 1863  218 NTA AbhyasNTA Abhyas 2020Molecular Basis of Inheritance Report Error

Solution:

The operator gene is a part of DNA between a promoter and a structural gene, where repressor binds to stop the activity of RNA polymerase.
An operon contains operator gene, regulator gene, represser, structural genes and promoter gene. In the operon concept, the operator gene interacts with represser protein produced by the regulator gene to switch off structural gene transcription. The regulator gene functions as a repressor and controls chemical synthesis by inhibiting transcription of mRNA. In E. coli, two types of operons are recognized, the lac operon and tryptophan operon.
1. The regulation of lac operon by a repressor is called negative regulation.
2. Lac operon is switched in the presence of lactose (substrate), an inducible operon.
Solution