Gene Expression

Gene Expression

Regulatory gene
1. these genes are expressed continuously and at a low rate, they also create the repressor
2. differential gene expression
  1. the expression of different genes by cells with the same genome
3. mutation in regulatory gene
  1. a mutation may lead to the increased production of a certain gene, which can lead to cancer
Operons
1. lactose operon
  1. can be switched off by the lac repressor, which is active by itself
  2. inducer
    1. a small molecule that inactivates the repressor
2. inductible operon
  1. an operon whose synthesis is induced by a chemical signal
3. operator
  1. an "on-off switch" that controls a cluster of functionally related genes, it controls the access of RNA polymerase to the genes
4. the operator, the promoter, and the genes they control make up an operon
Types of cells
1. Prokaryotic
  1. a single-celled organism that has a nucleus but no organelles
2. Eukaryotic
  1. cells found in multicellular organisms that have a nucleus and organelles
Molecules,Enzymes, and Proteins
1. repressor
  1. binds to the operator and blocks attachment of RNA ploymerase to the promoter, preventing the transcription of genes
2. promoter
  1. a site where RNA polymerase binds to DNA and begins transcription
3. corepressor
  1. a small molecule that works together with the repressor to switch an operon off
4. activator
  1. a protein that binds to DNA and stimulates transcription of a gene

Resumo de Recurso

	Criado por laurachavarry quase 10 anos atrás