RNA Synthesis Flashcards
Which is the biggest and smallest chromosome in the karyotype?
1= biggest and 22= smallest
What protects the ends of the chromosomes?
Telomere
What is the definition of a gene?
Unit of hereditary, or a DNA segment containing instructions for making a particular product
Why is the promoter region important?
Turns the gene on/off
Which of introns/Exons is expressed?
Exons are Expressed (remember the E’s)
Introns are spliced out
Where would you find an untranslated region (UTR)?
Part of the first and last exon
What is transcription? (General overview)
Synthesis of mRNA from DNA
What is translation? (General overview)
Nucleic acid ->protein
What genes do RNA polymerase 1 transcribe?
Most ribosomal RNA (rRNA)
What genes do RNA polymerase 2 transcribe?
Protein coding, miRNA and non coding RNA
What genes do RNA polymerase 3 transcribe?
tRNA, 5s rRNA and other small RNAs
How does the cell respond so quickly to changes in its environment?
Lots of polymerases can work simultaneously on the gene to make lots of copies of the gene
What molecules do you need for RNA synthesis?
- DNA template
- RNA polymerase 2
- ribonucleotide
- buffers
- transcription factors
What is a transcription factor?
Proteins required to initiate or regulate transcription in eukaryotes
How do transcription factors work?
- TATA box (promoter) recognised by the TBP subunit or TFIID
- other transcription factors bind then RNA polymerase2 assembles at the promoter forming the transcription initiation complex
- TFIIH (helicase) pulls apart the helix and phosphorylates RNA polymerase 2
- phosphorylated RNA polymerase 2 is released from the complex and begins transcription
