RNA - Gulf Coast State College

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Biology Partnership
(A Teacher Quality Grant)
RNA and Protein Synthesis
Nancy Dow
Jill Hansen
Tammy Stundon
October 20, 2012
Gulf Coast State College
Panhandle Area Educational Consortium
5230 West Highway 98
753 West Boulevard
Panama City, Florida 32401
Chipley, Florida 32428
850-769-1551
877-873-7232
www.gulfcoast.edu
Pre-test
Q and A board
What is RNA
How do we use RNA?
What are the different forms of RNA?
How do we produce an actual human
from just a series of letters??
Florida Next Generation
Sunshine State Standards
SC.912.L.16.3 Describe the basic process of DNA replication and
how it relates to the transmission and conservation of the
genetic information.
Also Assesses
SC.912.L.16.4 Explain how mutations in the DNA sequence may
or may not result in phenotypic change. Explain how mutations in
gametes may result in phenotypic changes in offspring.
SC.912.L.16.5 Explain the basic processes of transcription and
translation, and how they result in the expression of genes.
SC.912.L.16.9 Explain how and why the genetic code is universal
and is common to almost all organisms
Florida Next Generation
Sunshine State Standards
Benchmark Clarifications
• Students will describe the process of DNA replication and/or its role
in the transmission and conservation of genetic information.
• Students will describe gene and chromosomal mutations in the DNA
• sequence.
• Students will explain how gene and chromosomal mutations may or
may not result in a phenotypic change.
• Students will explain the basic processes of transcription and/or
translation, and their roles in the expression of genes.
• Students will explain that the basic components of DNA are universal
in organisms.
• Students will explain how similarities in the genetic codes of
organisms are due to common ancestry and the process of inheritance.
Florida Next Generation
Sunshine State Standards
Content Limits
• Items requiring the analysis of base pairs for gene
mutations are limited to changes in a single gene.
• Items may refer to but will not assess the cell cycle,
mitosis, and/or meiosis.
• Items will not require memorization of specific conditions
resulting from chromosomal mutations.
• Items may refer to the process of meiosis in the context of
mutations but will not assess meiosis in isolation.
• Items addressing transcription or translation will not
require specific knowledge of initiation, elongation, or
termination
Blame it on the DNA
Structure of DNA
 DNA is made of
subunits called
nucleotides
 DNA nucleotides are
composed of a
phosphate, deoxyribose
sugar, and a nitrogencontaining base
 The 4 bases in DNA are:
adenine (A), thymine
(T), guanine (G), and
cytosine (C)
Remember Replication?
8
Hold up,
wait a minute….
• DNA is only found in the
nucleus
• Who we are, how we look,
and the mechanisms that
make our body function are
all determined by proteins
• Proteins are only made in the
ribosome..
Why do we need both DNA and RNA?
• DNA holds
all the
genetic
information
• DNA
damage =
mutation
• Safer in the
nucleus
• RNA acts as
messenger
Why do we need both DNA and RNA?
Central Dogma holds that genetic information is expressed in a
specific order. This order is as follows
Central Dogma Video
DNA vs
RNA
Sugar
Bases
Strand
DNA vs RNA
Types of RNA
RNA Foldable
2
Types of
RNA
1
2
3
1
3
.
Three Types of RNA
1. Messenger RNA
(mRNA) copies DNA’s
code & carries the
genetic information to
the ribosomes
2. Ribosomal RNA (rRNA),
along with protein,
makes up the
ribosomes
3. Transfer RNA (tRNA)
transfers amino acids to
the ribosomes where
proteins are synthesized
Protein Synthesis: Step 1
DNA unwinds and mRNA is
made complementary to the
DNA
A=U
G=C
Transcription –the
making of messenger
RNA (mRNA) from
DNA in the nucleus
3 nitrogen bases in mRNA is called a codon
Protein Synthesis: Step 1
Where to start?
1. DNA unzips along hydrogen bonds
2. Free RNA nucleotides pair with the
complementary DNA bases (C-G
and U-A)
along the exposed DNA strand
forming an RNA transcript
3. RNA transcript released
from the DNA
4. DNA closes again
Protein Synthesis: Step 1
The transfer of information in the
nucleus from a DNA molecule to
an RNA molecule
• Only 1 DNA strand serves as
template
• Starts at promoter DNA (TATA)
• Ends at terminator (AAAAA)
• When complete, preRNA
molecule is released
Protein Synthesis: Step 1 ½
Not all the RNA
codes for something!
• A specialized nucleotide is added to the
beginning of each mRNA molecule which
forms a cap. It helps the mRNA strand
bind to a ribosome and prevents the
strand from being broken down too fast.
• The end of the mRNA molecule gets a
string of AAAA nucleotides (poly A tail)
that helps the mRNA molecule exit the
nucleus.
• The extra footage takes the form of
nucleotide segments that are not included
in the final protein.
Cleaning Up the Message
• Contains unwanted bases
• The ‘junk’ sequences (called
introns) are removed from the
message and the remaining
sequences (exons) are linked
together to produce a
sequence of codons that will
translate into a polypeptide.
• This process occurs before the
message leaves the nucleus.
Protein Synthesis: Step 1 ½
There’s
Junk in
My
DNA!
Final processing of the mRNA includes removal of
introns, leaving the exons to direct protein synthesis
Let’s Catch Up
DNA Codes
for RNA,
Which Codes
for Protein
The Language of Proteins
• Each 3 nucleotide
sequence in an
mRNA strand is
called a codon.
• Each codon codes for
a 1 amino acid.
• The codon sequence
codes for an amino
acid using specific
rules. These specific
codon/amino acid
pairings is called the
Genetic Code.
The Language of Proteins
• There are 64 (43) possible
codes, but only 20 amino acids.
• More than 1 triplet may code for
the same amino acid. This is
fine as long as no triplet can
code for more than one a.acid.
• Note that several codons can
also act as start (AUG) or stop
(UAA) signals.
Toss the Ball Review
The Genetic Code
Codon Music
Time to
Practice!
Mutations
• Mutation: change in DNA
• If a base is substituted or
deleted, the triplet(s) are
different
• This sometimes leads to
difference in the protein
Putting it All Together
Putting it All Together
1) rRNA (ribosomal RNA) attaches to mRNA and starts
reading the codons
2) tRNA (transfer RNA) – carries amino acids and
attaches them to the growing protein chain
3) When protein production is complete, the ribosome
releases the protein chain
Putting it All Together
Structure
• Two subunits, each composed of ribosomal RNA (rRNA) and protein
Function
• Bring tRNA bearing an amino acid close enough to mRNA to interact
– Permit alignment of anticodon and codon
DNA Codes for RNA,
Which Codes for Protein
Transcription
Translation
39
Scavenger hunt
Follow Up
Q/A board
Post Test
UAG
Try It - Simulations
Cool Stuff
Awesome
Scarf
Genome Quilts
From Gamer to Scientist
Some Other Goodies
•• Trippy
Protein
Synthesis
Dance Dance
Trippy
Protein
Synthesis
• http://www.youtube.com/watch?v=gqvYOr78THo (Blame it on the
• Tik
DNA)Tok (Protein Synthesis)
•• http://www.youtube.com/watch?v=_Q2Ba2cFAew&feature=related
Translation
Mario
Style
(Central dogma)
•• The
Cell Will Survive (Sing Along)
http://www.youtube.com/watch?v=bpMhgAGybe4
•• http://www.youtube.com/watch?v=ZPlnDzkBrpc
(mario translation)
Genetic Music
• http://www.youtube.com/watch?v=5ldkJxCzXak (sing along)?
•• DNA
Song
http://www.youtube.com/watch?v=tQv5Ho8zsKI
codon bell ringer
• DNA, Hotpockets, and the Longest Word Ever
• http://www.youtube.com/watch?v=tVrkBJz9q0g Born to be wildtype
(bad singing)
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