FoM:L3 - RNA processing and translation Flashcards
1
Q
How is mRNA processed in Eukaryotes?
A
- addition of 5’ cap
- addition of a poly A tail
- splicing of introns
2
Q
Outline the 5’ cap in mRNA processing
A
- 5’ end capped
- adding methylated G
- distinguish mRNAs from other RNAs
3
Q
Outline the addition of a poly A tail in mRNA processing
A
- 3’ end polyadenylated
- string of A nucleotides
- signal is coded in DNA
- proteins bind to poly A tails to stabilise
4
Q
Outline splicing in mRNA processing
A
- introns removed from primary RNA
- consensus sequences define exon-intron boundaries/splice sites
- splicosome (proteins and non-coding RNAs)
- removed through formation of a lariat
5
Q
What are alternative promoters?
A
alternative exon 1 or alternative internal promoters
6
Q
What is alternative splicing?
A
- splicing of exons in anything other than a sequential manner
- different protein isoforms
- regulated by RNA biding proteins
7
Q
What is RNA export?
A
- through nuclear pores, highly selective
- needs to be mature/fully processed