Key points: summarized from chapter 14

1. Key points: summarized from chapter 14 RNA processing

2. Outline: we will focus on mRNA processing • Overview of the Central Dogma • Introns versus exons • What is a codon • Steps of pre-mRNA processing • Eukaryotes versus prokaryotes

4. 3 steps of mRNA processing occurs in the nucleus of eukaryotes 5’ CAP Poly-A tail Splicing

5. The 5’Cap

8. The Poly-A Tail

9. Cleavage by endonuclease

10. Basic steps of poly-Adenylation

11. Splicing Spliceosome Requires RNA + proteins Function as enzymes Self splicing Only RNA! Function as enzymes!

12. Spliceosome Meet the spliceosome

13. Splicesome: 3 components are required Note some important aspects of the 5’ and 3’ ends 5’ phosphodiester of G 2’ OH of A lariat

16. Where does splicing occurs?

17. Self-Splicing mRNA’s

18. Common characteristic of self-splicing mRNA’s

19. Comments on Alternative processing methods First: What are the methods of mRNA processing discussed so far? 5’ CAP 3’ Poly A Tail Intron Splicing

20. Alternative processing methods • Alternative splicing • Multiple 3’cleavage sites • RNA editing

23. And alternative splicing example Thryoid BRAIN

25. Silencing or interfering RNAs • siRNA • miRNA

26. Onto translation chapter 15