Studied by 3 peopleDNA vs. RNA Base pairing rules
DNA: A-T C-G
RNA: A-U C-G
DNA vs. RNA strand numbers
DNA = Double Stranded
RNA = Single Stranded
mRNA Structure
Single stranded and linear
rRNA Structure
Single Stranded and Globular
tRNA Structure
Single stranded and clover leaf
Why do we need to do Transcription?
DNA cannot leave the nucleus but the mRNA can, so an mRNA takes its place.
What is the product of Transcription?
RNA transcript
Where does transcription happen?
Euk-Nucleus
Prok-Cytoplasm
Helicase
unzips DNA
Transcription Factors
look for promoter region
Promoter Region
DNA Nucleotides sequence flag down RNA Polymerase so it can bind
TATA Box
Region where transcription begins; place where RNA Polymerase binds to DNA
RNA Polymerase
Transcribe genetic information from DNA to RNA sequence; 3’ to 5’
Complementary Base Pairing Rules
(A→U, T →A, C→G, G→C)
Termination Sequence
AAUAAA;
How quickly after the termination sequence does transcription end?
10-35 nucleotides after termination sequence
Where does translation happen?
Cytoplasm (More specifically the ribosomes)
What is the product of translation?
Proteins
How do we read and process mRNA?
Read in sets of triplets called codons
tRNA in translation
carries amino acids to ribosome based on mRNA
Anticodons
sequence at end of transfer RNA
Peptide Bonds
the bonds responsible for attaching amino acids to the polypeptide chain
Ribosomes
Big and small ribosomal subunit attach where tRNA attaches connect amino acids
5’GTP Cap
Attach to small ribosomal subunits
Small Ribosomal Subunit
Attaches to Large Ribosomal Subunit
Start anticodon
Part of tRNA that had complementary nucleotides for codon
Large Ribosomal Subunit
Attaches to Small Ribosomal Subunity
A Site
tRNA attaches here and takes amino acids from P site
P Site
tRNA from A Site moves here and P tRNA moves to next site
E Site
tRNA from P site moves here to exit
Methionine
AUG - Start codon amino acid
Stop Codon
Sequence that signals stop: UAA, UGA, UAG
Release Factor
protein that recognizes stop codon and ends translation
Point Mutations
Change only one base pair; most mutations fit under this category
Substitution definition
Swap out base pairs for a different base pair
Types of Substitution
Silent, Missense, Nonsense
Silent
Has no effect on the amino acid; inserted at wobble position
Wobble position
third base pair in codon
Missense
Change the amino acid being created (can change shape or function of entire polypeptide); 1st or 2nd base pair in codon
Nonsense
Creates a stop codon and ultimately creates a nonfunctional polypeptide
Frameshift definition
Changing the reading frame of the code
Frameshift types
Insertion and Deletion
Insertion
Nucleotide is added to the gene and changes all amino acids after that; shifts reading frame to the right
Deletion
Nucleotide is removed from the gene; all amino acids change after that; shifts reading frame to the left
Note
Flashcard