goal 3.01b: protein synthesis and gene regulation
DESCRIPTION
Goal 3.01b: Protein Synthesis and Gene Regulation. Genetics: A whole new spin on “ who’s who .”. Central Dogma. From Gene to Protein. Bodies Cells DNA. Bodies are made up of cells All cells run on a set of instructions spelled out in DNA. - PowerPoint PPT PresentationTRANSCRIPT
Goal 3.01b: Protein Synthesis and Gene Regulation
Goal 3.01b: Protein Synthesis and Gene Regulation
From Gene to Protein
Central Dogma
Bodies are made up of cells All cells run on a set of instructions
spelled out in DNA
Bodies Cells DNA
What makes it possible for different people…What makes it possible for different people…
… to have different faces?
i.ivillage.com www.learnwell.org
symonsez.files.wordpress.com
…to
be
diff
eren
t he
ight
s?
neveryetmelted.com
www.saidaonline.com
…to have different colored eyes?
Makes this protein…Makes this protein…
or this protein…or this protein…
or this protein!or this protein!
Each DNA makes a specific protein.
Those proteins
give us our looks.
cr4.globalspec.com
gamespot.com
Remember… Bases match together
A pairs with T A : T
C pairs with GC : G
weak bonds between bases join 2 strands can separate easily
Now it is time to find out how DNA manages to create so many different
kinds of organisms using only FIVE pieces of information!
What do we know? DNA
DNA is the genetic information
Proteins proteins run living organisms enzymes
all chemical reactions in living organisms are controlled by enzymes (proteins)
structure all living organisms are built out of proteins
DNA is the instructions for making proteins
What else do we know? DNA
DNA is in the nucleus want to keep it there =
protected
Proteins made by a “protein
factory” in cytoplasm ribosomes
Need to get gene (DNA) information from nucleus to cytoplasm need a messenger! need a copy of DNA mRNA
• deoxyribose sugar • nitrogen bases
– G, C, A, T• T = thymine
– T : A– C : G
• double stranded
• ribose sugar • nitrogen bases
– G, C, A, U• U = uracil
– U : A– C : G
• single stranded
DNA RNA
mRNADNA
transcription
nucleus cytoplasm
proteintranslation
trait
A brief overview of what happens…
DNA (double helix) is too big to go through the pores in the nuclear envelope.
The problem with DNA…
RNA (single helix) is small.
DNA gives its information to mRNA (messenger RNA) to carry out of the nucleus.
TOO BIG!
Just right.
• Making mRNA from DNA• DNA strand is the
template (pattern)– match bases
• U : A• G : C
• Enzyme– RNA polymerase
mRNA
TRANSCRIPTION
Making mRNA from DNA
A G GGGGGT T A C A C T T T T TC C C CA A
TRANSCRIPTION
A G GGGGGT T A C A C T T T T TC C C CA A
U U U U U
• Double stranded DNA unzips
A G GGGGGT T A C A C T T T T TC C C CA A
TRANSCRIPTION
• Use RNA polymerase• Match free floating RNA
bases to DNA bases on one of the DNA strands
U
A G GGGGGT T A C A C T T T T TC C C CA A
U
UU
U
U
G
G
A
A
A C CRNA
polymerase
C
C
C
C
C
G
G
G
G
A
A
A
AA
TRANSCRIPTION
Free-floating nucleotides
DNA
mRNA
TRANSCRIPTION
T A C G C A T T T A C G T A G C G G
l I I I I I I I I I I I I I I I I I
A U G C G U A A A U G C A U C G C C
Transcription Animationhttp://www.stolaf.edu/people/giannini/flashanimat/molgenetics/transcription.swf
U instead of T is matched to AU instead of T is matched to A
We are transcribing DNA into RNA.We are transcribing DNA into RNA.
What do we know NOW? DNA
instructions remain in nucleus
mRNA has the instructions for building
proteins from DNA
Proteins built as chains of amino acids
What reads RNA? need a mRNA reader! rRNA in ribosomes
aa
aa
aa
aa
aa
aa
aa
U C CCCCCA A U G U G A A A A AG G G GU U
aa
mRNAmRNA
From gene to protein
DNADNA
nucleus
ProteinProtein
TraitTrait
U C CCCCCA A U G U G A A A A AG G G GU UrRNA
ribosome
mRNA leaves nucleus through
nuclear poresrRNA inside the ribosomes synthesize amino acids to
make a protein using instructions on mRNA
Transcription
CELL
aa
aa aa
aa
aa
aa
Translation
mRNA has the instructions for building proteins
from DNA
Proteins built as chains of amino acids linked by
peptide bonds
What reads mRNA? ribosome
What brings the right amino acid to attach to the protein chain? need an amino acid transporter!
tRNA
aa
a
aaa
aa
aa
aa
What do we ALSO know now?U C CCCCCA A U G U G A A A A AG G G GU U
ribosome
Peptide bonds
mRNAmRNA
From gene to protein
DNADNA
nucleus
ProteinProtein
TraitTrait
U C CCCCCA A U G U G A A A A AG G G GU Uribosome
Transcription
cytoplasm
CELL
aa
aa aa
aa
aa
aa
Translation
aa
tRNA carries the correct amino acid (based on the
mRNAcode) to the ribosome.
Protein SynthesisProtein SynthesisLet’s build a flow chart!
TRANSCRIPTIONDNA gives mRNA blueprints for making a specific protein.
mRNA carries the blueprints out of the nucleus to the cytoplasm and finds a ribosome.
TRANSLATIONrRNA reads the mRNA inside the ribosome.
tRNA brings the correct amino acid to the mRNA.
An amino acid chain is built: PROTEIN.
Protein give us our traits.
BUILD DNA AND DISCOVER GENES!http://learn.genetics.utah.edu/content/begin/dna/
1. What is DNA?2. What is a Gene?3. Build a DNA Molecule.
How does tRNA know which amino acid to bring?
• When mRNA leaves nucleus it has a blueprint of DNA’s instructions.
• mRNA goes to ribosomes in cytoplasm• Ribosomes read the blueprint on mRNA.
aa aa aa aa aa aa aa aa
mRNA
U C CCCCCA A U G U G A A A A AG G G GU Uribosome
Using the template…
TACGCACATTTACGTACGCGGDNA
AUGCGUGUAAAUGCAUGCGCCmRNA
Met Arg Val Asn Ala Cys Alaprotein
?
How can you code for 20 amino acids with only 4 nucleotide bases (A,U,G,C)?
AUGCGUGUAAAUGCAUGCGCC
mRNA codes for proteins in triplets
TACGCACATTTACGTACGCGGDNA
AUGCGUGUAAAUGCAUGCGCCmRNA
Met Arg Val Asn Ala Cys Ala
Aminoacid
?
ribosome
Codon = set of 3 bases
Anticodon = set of 3 basesUAC
The code is UNIVERSAL!
• Since all living organisms… – use the same DNA– use the same code
book– read their genes the
same way
AUG
What amino acids are
coded for by these
codons?
UGAACUAACGAG
• For ALL life!– Uses only 4 bases for
ALL life. (strongest support for a common origin for all life)
• Code is redundant– several codons for each
amino acid– mutation insurance!
The mRNA code
Start codon AUG methionine
Stop codons UGA, UAA, UAG
TACGCACATTTACGTACGCGGDNA AUGCGUGUAAAUGCAUGCGCCmRNA
Pro
Ala
MetVal
Leu
Met
Transcription and Translation Builder http://learn.genetics.utah.edu/content/begin/dna/transcribe
/
ArgArg
You Transcribe and Translate a Gene!http://learn.genetics.utah.edu/content/begin/dna/
Step Through Translationhttp://bcs.whfreeman.com/thelifewire/content/chp12/1202003.html
1. Transcribe and Translate a Gene2. What makes a firefly glow?
DNA Translation Real Time and Interactive http://www.dnai.org/a/index.html
Transcription in Real Time (view as class) http://www.dnalc.org/resources/3d/TranscriptionBasic_withFX.htmll
Can you tell the story?
DNA
transcription
ribosome
tRNA
aminoacids
protein
translation
mRNA
29:08 Central Dogma Biologix__Translation_and_Protein_Synthesis
A Quick Review….
1. What is this molecule?
3.What is this process?
2.What is this molecule?
4.What is this structure?
8.What is this process?
6.What are these molecules?
5.What is this molecule?
7.What is this molecule?
DNA TAC GCA TGG AAT TAC GCA TGG AAT
Substitution/Point Mutation = one base is changed and one amino acid is changed.
Substitution/Point Mutation = one base is changed and one amino acid is changed.
mRNA AUG CGU ACC UUA AUG CAU ACC UUA
Protein Met Arg Thr Leu Met His Thr Leu
DNA TAC GCA TGG AAT TAC GTA TGG AAT
Insertion Mutation = one base is inserted and everything downstream is changed.
Insertion Mutation = one base is inserted and everything downstream is changed.
mRNA AUG CGU ACC UUA AUA GCA UAC CUU A
Protein Met Arg Thr Leu Ile Ala Tyr Leu
T
DNA TAC GCA TGG AAT TAT CGT ATG GAA T
http://highered.mcgraw-hill.com/sites/0072556781/student_view0/chapter11/animation_quiz_4.html
EXPLAIN DIVERSITY…
• Each organism has a unique sequence of DNA.• The DNA sequence determines the order of amino acids in the organism’s proteins.• The order of amino acids determines the shape that the protein made will take.• The shape of the protein determines what it can do.• What the protein does determines everything about the organism.• Gene Regulation determines when a sequence of DNA will be put to use and when it won’t.
Gene Regulation…Keeping Control!
Every species has its own number of chromosomes in
each cell.
OrganismNumber of
Chromosomes
Cat 32
Chimpanzee 48
Dog 78
Cow 60
Human 46
Horse 64
Pea plant 14
Corn plant 20
Mosquito 6
Honeybee 32
Sugarcane 80
Sand dollar 62
Notice:More is not always
better... Sometimes it’s just more.
Remember…a section on a chromosome that codes for a specific trait is called a GENE.
And…
There are lots and lots of genes on each chromosome!
The job of a gene is to control the production of proteins.
Not every gene is expressed (turned on) at the same time.
Gene Regulation = what controls when a gene is expressed and when it is not.
In bacteria, genes are in groups called Operons.
Example: E. coli that’s in our digestive system helps us break down milk.
Each Operon codes for a specific protein.
Baby features (birth – 5 yrs)
Child features (5 yrs – 12 yrs)
Teen features (12 yrs – 17 yrs)
Adult features (17 yrs – 60 yrs)
Elderly features (60 yrs – death)
RNA polymerase
Promoter Sequence = area “upstream”
(toward the 5’ end)
from the gene where the RNA polymerase
attaches.
Start Codon = set of three nucleotide bases
where transcription begins.
Stop Codon = set of three nucleotide bases
where transcription ends.
Terminator Sequence = area “downstream” from the gene where
the polymerase detaches.
Gene5’
3’
Lac operon
Are You Lactose Intolerant?
Here’s how we metabolize
milk…
Has to have a CAP to start.
Can NOT have a Repressor.
http://sumanasinc.com/
webcontent/animations/content/
lacoperon.html
Beadle and TatumOne gene, one protein.
Beadle and Tatum Experiment http://wps.prenhall.com/wps/media/objects/1552/1589869/web_tut/21_04/21_04_01a.swf
Gene Therapy: Introduction
What is Gene Therapy?
Using parts of a gene from a healthy cell to fix a damaged or sick cell.
How Gene Therapy
Works (Interactive)
http://www.edu365.cat/aulanet/comsoc/Lab_bio/simulacions/GeneTherapy/
GeneTherapy.htm
Don’t hate me because I’m beautiful…
Blame it on my GENES!
Any Questions?
img1.chakpak.com
Assignment:Coach Book L15