RNA Translation

RNA Processing

• End product is a mature RNA molecule that leaves the nucleus to the cytoplasm.

• Introns bad…… Exons good!

DNA

RNA

Protein

TRANSCRIPTION

TRANSLATION

Introns are pulled out and exons come together.

RNA Processing

pre-RNA molecule

intron intronexon exon exon

exon exon exon

Mature RNA molecule

exon exon exon

intron intron

splicesome splicesome

• Processing must occur before mRNA can be used to produce a correct protein through translation.

• the spliceosome catalyzes the reaction

RNA Post-Transcriptional

A. Messenger RNA (mRNA)

methionine glycine serine isoleucine glycine alanine stopcodon

protein

A U G G G C U C C A U C G G C G C A U A AmRNA

startcodon

Primary structure of a protein

aa1 aa2 aa3 aa4 aa5 aa6

peptide bonds

codon 2 codon 3 codon 4 codon 5 codon 6 codon 7codon 1

RNA Translation

U C A G

U

C

A

G

GACU

GACU

GACU

GACU

UUUUUCUUAUUG

CUUCUCCUACUG

AUUAUCAUAAUG

GUUGUCGUAGUG

phe

leu

leu

ile

met (start)

val

UCUUCCUCAUCG

CCUCCCCCACCG

ACUACCACAACG

GCUGCCGCAGCG

ser

pro

thr

ala

UAUUACUAAUAG

CAUCACCAACAG

AAUAAC

AAGAAA

GAUGACGAAGAG

tyr

stopstop

his

gln

asn

lys

asp

glu

UGUUGCUGAUGG

CGUCGCCGACGG

AGUAGCAGAAGG

GGUGGCGGAGGG

cys

stoptrp

arg

ser

arg

gly

First Base T

hird Base

Second Base

Virtually all organisms share the same genetic code “unity of life”

mRNA

• Carries instructions from DNA to the rest of the ribosome.

• Tells the ribosome what kind of protein to make

• Acts like an email from the principal to the cafeteria staff.

RNA Translation

rRNA

• Part of the structure of a ribosome• Helps in protein production

tRNA

A go-getter. Gets the right parts to make the right protein according to mRNA instructions

RNA Translation

B. Transfer RNA (tRNA)

amino acidattachment site

U A C

anticodon

methionine amino acid

RNA Translation

Table 14.2Types of RNA

Type of RNA Functions in Function

Messenger RNA(mRNA)

Nucleus, migratesto ribosomesin cytoplasm

Carries DNA sequenceinformation to ribosomes

Transfer RNA(tRNA)

Cytoplasm Provides linkage between mRNAand amino acids;transfers aminoacids to ribosomes

Ribosomal RNA(rRNA)

Cytoplasm Structural component of ribosomes

Figure 10.14

1 Codon recognition

Amino acid

Anticodon

AsiteP site

Polypeptide

2 Peptide bond formation

3 Translocation

Newpeptidebond

mRNAmovement

mRNA

Stopcodon

An example of translation:

http://learn.genetics.utah.edu/content/begin/dna/firefly/

Transcription / translationhttp://learn.genetics.utah.edu/content/begin/dna/transcribe/

Ribosomes

PSite

ASite

Largesubunit

Small subunit

mRNAA U G C U A C U U C G

Translation - making proteins

Nuclearmembrane

Transcription

RNA Processing

Translation

DNA

Pre-mRNA

mRNA

Ribosome

Protein

Eukaryotic Cell

Translation

• Three parts:1. initiation: start codon (AUG)2. elongation:3. termination: stop codon (UAG)

• Let’s make a PROTEIN!!!!.

Translation

PSite

ASite

Largesubunit

Small subunit

mRNAA U G C U A C U U C G

Initiation

mRNA

A U G C U A C U U C G

2-tRNA

G

aa2

A U

A

1-tRNA

U A C

aa1

anticodon

hydrogenbonds codon

mRNA

A U G C U A C U U C G

1-tRNA 2-tRNA

U A C G

aa1 aa2

A U

A

anticodon

hydrogenbonds codon

peptide bond

3-tRNA

G A A

aa3

Elongation

mRNA

A U G C U A C U U C G

1-tRNA

2-tRNA

U A C

G

aa1

aa2

A U

A

peptide bond

3-tRNA

G A A

aa3

Ribosomes move over one codon

(leaves)

mRNA

A U G C U A C U U C G

2-tRNA

G

aa1

aa2

A U

A

peptide bonds

3-tRNA

G A A

aa3

4-tRNA

G C U

aa4

A C U

mRNA

A U G C U A C U U C G

2-tRNA

G

aa1

aa2

A U

A

peptide bonds

3-tRNA

G A A

aa3

4-tRNA

G C U

aa4

A C U

(leaves)

Ribosomes move over one codon

mRNA

G C U A C U U C G

aa1

aa2

A

peptide bonds

3-tRNA

G A A

aa3

4-tRNA

G C U

aa4

A C U

U G A

5-tRNA

aa5

mRNA

G C U A C U U C G

aa1

aa2

A

peptide bonds

3-tRNA

G A A

aa3

4-tRNA

G C U

aa4

A C U

U G A

5-tRNA

aa5

Ribosomes move over one codon

mRNA

A C A U G U

aa1

aa2

U

primarystructureof a protein

aa3

200-tRNA

aa4

U A G

aa5

C U

aa200

aa199

terminator or stop codon

Termination

End Product

• The end products of protein synthesis is a primary structure of a protein.

• A sequence of amino acid bonded together by peptide bonds.

aa1

aa2aa3

aa4aa5

aa200

aa199

http://learn.genetics.utah.edu/content/begin/dna/transcribe/

Question:

• The anticodon UAC belongs to a tRNA that recognizes and binds to a particular amino acid.

• What would be the DNA base code for this amino acid?

Answer:

• tRNA - UAC (anticodon)• mRNA - AUG (codon)• DNA - TAC

Protein Processing

Post-translational processing –

• Proteins undergo many processes such as folding, cutting and other processes), before becoming the mature protein product

DNA

RNA

Protein

TRANSCRIPTION

TRANSLATION

Summarize the steps of translation from your text(pg 257 – 260)

An example of translation:

http://learn.genetics.utah.edu/content/begin/dna/firefly/

Transcription / translationhttp://learn.genetics.utah.edu/content/begin/dna/transcribe/

http://www.biostudio.com/demo_freeman_protein_synthesis.htm