gene regulation

what is gene expression

the process of reading the information stored within a gene to create a functional product (usually a protein)

what is gene regulation

the process in which gene expression is controlled

involves other genes turning the expression on / off

why does gene expression get regulated (2)

helps cells conserve energy

cells dont need to make proteins all the time so turning it off conserves energy

what is a regulatory gene

encode for proteins that control the expression of other genes. these proteins are called transcription factors

they can turn on / off gene transcriptions

structural genes

genes that encode for proteins not involved in gene regulation

examples of structural genes products (3)

enzymes

signalling molecules

structural components

operators

a segment of DNA to which a repressor bind

where are operators located

downstream of the promotor

what are operators used for

binding site for repressions or activator proteins

what happens if a repressor protein binds to the operator

RNA polymerase cannot move downstream from the promoter - inhibits transcription of gene

what happens if no repressor protein binds to the operator

RNA polymerase is free to move downstream from the promoter - allowing for transcription

gene regulation in eukaryotes vs prokaryotes

eukaryotes are very complex while prokaryotes are simple due to a lack of membrane bound organelles

what goes a eukaryote have that a prokaryote doesnt (6) in terms of gene regulation

transcription and translation inhibition

pre mRNA editing

degradation of mRNA

protein folding can be altered

proteins can be broken down

each gene is controlled by one promotor and terminator region

what does a prokaryote have that a eukaryote doesnt (4) in terms of gene regulation

transcription and translation occur in cytoplasm

genes can be repressed

genes can be induced

multiple genes can be between one promotor and terminator region