Download DNA Sequences

DNA Sequences
• Deoxyribonucleic acid (DNA) is a nucleic
acid that contains the genetic instructions
used in the development and functioning of
all known living organisms and some
viruses.
DNA Sequences
ULM/HHIM Summer Program
Project 3, Day 3, Part 1
• The main role of DNA is the long-term
storage of information.
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DNA Sequences
DNA Sequences
• DNA is often compared to a set of
blueprints or a recipe, or a code, since it
contains the instructions needed to construct
other components of cells, such as proteins
and RNA molecules.
• The DNA segments that carry this genetic
information are called genes, but other
DNA sequences have structural purposes, or
are involved in regulating the use of this
genetic information.
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DNA Sequences
• It is the sequence of these four nucleotides
along the polymer strands that encodes
information.
• These two strands run in opposite directions
to each other and are therefore anti-parallel.
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DNA Sequences
• Chemically, DNA consists of two long
polymer strands of four simple units called
nucleotides.
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– Adenine (A)
– Cytosine (C)
– Guanine (G)
– Thymine (T)
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DNA Sequences
DNA Sequences
sense DNA strand
• Adenine is matched with thymine.
5’ ATGACGGAGCTTCGGAGCTAG 3’
3’ TACTGCCTCGAAGCCTCGATC 5’
antisense DNA strand
– A-T or T-A
• Cytosine is matched with guanine.
– C-G or G-C
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Central Dogma
DNA Sequences
DNA Sequences
• Transcription
DNA (DeoxyriboNucleic Acid)
Transcription (of the 3’ – 5’ DNA strand)
– Read the 3’ → 5’ DNA (antisense) strand.
mRNA (messenger RiboNucleic Acid)
– Complement the nucleotides read.
Translation
• T → A, C → G, and G → C
• A → U (Uridine)
Protein
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DNA Sequences
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DNA Sequences
antisense DNA strand
• Once we have a mRNA sequence, it can be
“translated” into amino acid codons.
3’ TACTGCCTCGAAGCCTCGATC 5’
5’ AUGACGGAGCUUCGGAGCUAG 3’
mRNA
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Second Nucleotide
DNA Sequences
U
First Nucleotide
• Sequences of codons are used to create
amino acids.
– There exist 64 codons
– Most all codons are three nuleotides in length.
– The 61 codons encode for one of the 20 amino
acids.
– The codon AUG is the start codon
– The codons UAG, UGA, UAA.
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A
G
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DNA Sequences
U
C
A
G
UUU Phenylalanine (Phe)
UCU Serine (Ser)
UAU Tyrosine (Tyr)
UGU Cysteine (Cys)
UUC Phe
UCC Ser
UAC Tyr
UUA Leucine (Leu)
UCA Ser
UAA STOP
UGA STOP
UGC Cys
UUG Leu
UCG Ser
UAG STOP
UGG Tryptophan
(Trp)
CUU Leucine (Leu)
CCU Proline (Pro)
CAU Histidine (His)
CGU Arginine (Arg)
CUC Leu
CCC Pro
CAC His
CUA Leu
CCA Pro
CAA Glutamine (Gln)
CGA Arg
CUG Leu
CCG Pro
CAG Gln
CGG Arg
CGC Arg
AUU Isoleucine (Ile)
ACU Threonine (Thr)
AAU Asparagine (Asn)
AGU Serine (Ser)
AUC Ile
ACC Thr
AAC Asn
AGC Ser
AUA Ile
ACA Thr
AAA Lysine (Lys)
AGA Arginine (Arg)
AUG Methionine (Met)
or START
ACG Thr
AAG Lys
AGG Arg
GUU Valine Val
GCU Alanine (Ala)
GAU Aspartic acid (Asp)
GGU Glycine (Gly)
GUC (Val)
GCC Ala
GAC Asp
GUA Val
GCA Ala
GAA Glutamic acid (Glu)
GGA Gly
GUG Val
GCG Ala
GAG Glu
GGG Gly
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GGC Gly
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DNA Sequences
mRNA
• Sequences of amino acids are used to create
proteins.
5’ AUGACGGAGCUUCGGAGCUAG 3’
StrThrGluLeuArgAlaStp
codons
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DNA Sequence Exercise 1
• Write your answers to the questions on the
DNA Sequence Exercise 1 Answer Sheet.
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