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Gene Expression DNA RNA Protein Transcription Translation What is the language of DNA?. DNA Double Helix- Deoxyribonucleic acid “ Genetic material of Life” “Twisted” ladder. Nucleotides - Building Blocks. Nucleotide- Base, sugar, phosphate group. Nitrogen Bases. Purine , Adenine, - PowerPoint PPT Presentation
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Gene ExpressionDNA RNA Protein
Transcription TranslationWhat is the language of DNA?
DNA Double Helix- Deoxyribonucleic acid“Genetic material of Life” “Twisted” ladder
Nucleotides- Building Blocks
Nucleotide- Base, sugar, phosphate group
Nitrogen Bases
• Purine, • Adenine, • Guanine,
• Pyrimidine. Thymine,• Cytosine• “Y”- pyrimidine
Complimentary Base pairs
• Adenine - -Thymine• (A T & T) - two• Cytosine - - - Guanine
• Combine by double / triple bonds.
• (-) = Hydrogen bonds
DNA Double Helix
DNA ReplicationDNA replication (chromosomes replicated during S phase) is SEMI-CONSERVATIVE.
http://www.youtube.com/watch?v=AGUuX4PGlCc
What is semi-conservative? MatchOriginal two strands of DNA (at left)- Which figure below represents semi- conservative copying?
A
C
B
D
• Replicated DNA contains ½ one Old and ½ one New – why? Fig. 11-9 Iguana, 9-9 Manatee
• Reduce mistakes and is faster.
Replication
DNA Replication http://www.johnkyrk.com/DNAreplication.html Simple Best DNA- http://www.lewport.wnyric.org/jwanamaker/animations.htm
DNA Replication
• DNA is “unzipped” by DNA Helicase (Helix is shape of DNA = spiral)
DNA Replication New bases added by DNA Polymerase. 5’ to 3’,
direction. (like one end to other).
DNA Replication
Give complimentary side of this sequence
• DNA below• TAC/ACC/TAG/CTT/TTGACGGGGAACCCCATT• ATG/TGG/ATC/GAAAACTGCCCCTTGGGGTAA• DNA is proofread and errors are only 1 in
every Billion nucleotides!
Objectives• Compare The structure of RNA with that of
DNA.
• Summarize Transcription- DNARNA
Gene Expression/ Central Dogma for Molecular Biology• DNA(Transcription) RNA (Translation)
Proteins
Decoding the Information in DNA
• Traits- eye color, hair color determined by proteins, built according to instructions coded in DNA.
• Proteins however, not built directly from DNA but from Ribonucleic acid.
• Ribonucleic acid (RNA) nucleic acid similar to DNA.
DNARNA- Transcription• DNA is like a book, Chapters are
Chromosomes, Sections are Genes• DNA stays protected in nucleus• ** (Do not want to damage)**• RNA is copied from shorter sequence
of DNA, leaves nucleus• RNA is Working copy of DNA- leaves
nucleus.
Transcription- (Nucleus)
Removal of introns After Transcription- mRNA leaving is called exons = GENE
3 Types of RNA
Ribonucleic Acid
Comparing DNA/RNA- 3 differences
DNA• Two strands• Deoxyribose Sugar• Thymine
A- - TC ---G
RNA• Single strand• Ribose Sugar• Uracil• NO Thymine• A-U• C-G
Transcription- (Nucleus)• RECALL- DNA/DNA• TAC/ACC/TAG/CTT/TTGACGGGGAACCCCATT• ATG/TGG/ATC/GAA/AACTGCCCCTTGGGGTAA
• Given DNA sequence below• What is the complimentary mRNA? Recall NO
Thymine!• TAC/ACC/TAG/CTT/TTG/ACG/GGG/AAC/CCC/ATT• AUG/UGG/AUC/GAA/AAC/UGCCCCUUGGGGUAA
Objectives
• Outline The major steps of translation.
• Relate Codons to the sequence of amino acids that results after translation.
• Discuss The evolutionary significance of the genetic code.
Translation: Assembling Proteins
Section 1 From Genes to ProteinsChapter 10
Translation-(Cytoplasm) RNA Proteins
• RNA Code is read • CODON – “Code on” mRNA- messenger
RNA• CODON = 3 Bases ON- results in Amino
Acid• Chain of Amino Acids makes protein
(polypeptide)
Translation RNA Protein
• UGUUAUAUCGAAAACUGCCCCUUGGGGUAA• Read every 3 bases= CODON• UGU/UAU/AUC/GAA/AAC/UGC/CCC/UUG/GGG/UAA
Codon- sheet• Why read every 3 bases? • Codon combinations must cover 20 different
AA- Amino Acids • 41 = 4• 42 = 16• 43 = 64 CHECK!• Results in 64 combinations• Start sequence AUG.• End sequence UAA, UAG, UGA.
Codes in mRNA
Translation RNA Protein
• UGUUAUAUCGAAAACUGCCCCUUGGGGUAA• Read every 3 bases= CODON• UGU/UAU/AUC/GAA/AAC/UGC/CCC/UUG/GGG/UAA
Amino Acids
• Amino acids can be• Polar/Non Polar• Hydrophobic/Hydrophilic • Acidic/Basic• Depending on sequence this will make a
shape = GENE
Translation: Forming the First Peptide Bond
Section 1 From Genes to ProteinsChapter 10
tRNA
• tRNA- Transfer RNA, “transfers” the Amino Acid to the ribosome to make protein
• tRNA is complimentary to mRNA, “lock & key” fit. Every codon has only one Anticodon.
• AUG/CAA- Codon• UAC/GUU- Anticodon- specific AA• Met-Glu- Amino acids
Translation: Assembling Proteins
Section 1 From Genes to ProteinsChapter 10
Video showing transcription/translation
• https://www.youtube.com/watch?v=erOP76_qLWA
Mutations
Major Types of Mutations
Mutation- Change in sequence of the DNA- deoxyribonucleic acid
• A. Chromosomal- whole, parts added or deleted, sections translocated to other chromosomes.
• B. Gene- –1. Point–2. Frameshift.
Somatic-affects individual- EX. skin cancer.Genetic- affects sperm or egg affects
offspring.
Gene mutations1. Point mutation- affects onenucleotide fig. 11-7 p. 230 Iguana
• p. 219 Manatee • Ex. • TAC GTT CCA, change TAC GTA CCA, • If this makes different codon
(language of genetics), = new amino acid
Point mutation analogy
• The dog ran out the box• Point mutation Change D and C.• The Cog ran out the box.
Frame shift mutationB. Frame shift mutation- removal of a
base(s) or insertion of a segment, results in different “reading” of gene. CODON= 3 bases.
• TAC GTT CCA- original sequence. T(AC G)TT CCA remove first (T) ACG TTC CA…. TA)C GTT CCAinsert T TTA CGT TCC A
Frame shift mutation analogy
• The dog ran out the box• TTh edo gra nou tth ebo x. ADDITION of a T• Heg ogr ano uth heb ox DELETION of a T
Genetic Code- Evolutionary significance
• The code AUG/CCC/, whether in human or oak tree, or mosquito, etc.. makes same amino acids….Met--Pro
• This shows relatedness of all living organisms.
How can a glow in the dark gene from Jellyfish work in a pig?
• DNA is a code like words if it fits and makes sense, then it can be used.
• The dog ran down the street.
• The cat ate a bird.
• The dog ate a bird. Still makes “sense”.