Revise later
SpaceTo flip
If confident
All Flashcards
What is a promoter?
Specific DNA region upstream of a gene's start site, acting as an 'on' switch.
Define RNA Polymerase.
The enzyme that transcribes DNA into RNA.
What are transcription factors?
Proteins that help RNA polymerase bind to the promoter.
Define TATA box.
A DNA sequence within the promoter recognized by the TATA-binding protein (TBP).
What are repressors?
Proteins that block RNA polymerase from binding to the promoter, preventing transcription.
Define differential gene expression.
The process where different genes are expressed at different levels in different cells or at different times.
What are microRNAs (miRNAs)?
Non-coding RNAs that bind to the 3'UTRs of target mRNAs, inhibiting translation or promoting mRNA degradation.
What are Small Interfering RNAs (siRNAs)?
Double-stranded RNAs processed by RISC that target specific mRNAs for degradation.
What are PIWI-interacting RNAs (piRNAs)?
Small non-coding RNAs that silence transposable elements.
What are the key differences between enhancers and silencers?
Enhancers: Increase transcription. | Silencers: Decrease transcription.
Differentiate between miRNAs and siRNAs in gene regulation.
miRNAs: Inhibit translation or promote mRNA degradation. | siRNAs: Target specific mRNAs for degradation.
What is the effect of a mutation in the promoter region?
Altered or abolished gene expression due to impaired RNA polymerase binding.
What is the effect of increased miRNA activity?
Decreased expression of target genes due to inhibited translation or mRNA degradation.
What is the effect of misregulation of cell cycle genes?
Uncontrolled cell division, potentially leading to tumors or abnormalities.
What happens if a repressor protein is mutated and non-functional?
Increased gene expression, as the repressor can no longer block RNA polymerase binding.
What is the result of siRNA binding to mRNA?
mRNA degradation, preventing protein synthesis.