480 likes | 770 Views
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,
E N D
Gene ExpressionDNA RNA ProteinTranscription TranslationWhat is the language of DNA?
DNA Double Helix- Deoxyribonucleic acid“Genetic material of Life” “Twisted” ladder
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 Replication DNA replication (chromosomes replicated during S phase)is SEMI-CONSERVATIVE. http://www.youtube.com/watch?v=AGUuX4PGlCc
What is semi-conservative? Match Original two strands of DNA (at left)- Which figure below represents semi- conservative copying? B A C 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 Replicationhttp://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 • CompareThe structure of RNA with that of DNA. • SummarizeTranscription- 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.
Removal of intronsAfter Transcription- mRNA leaving is called exons = GENE
Comparing DNA/RNA- 3 differences DNA RNA Single strand Ribose Sugar Uracil NO Thymine A-U C-G • Two strands • Deoxyribose Sugar • Thymine A- - T 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 • OutlineThe major steps of translation. • RelateCodons to the sequence of amino acids that results after translation. • DiscussThe evolutionary significance of the genetic code.
Chapter 10 Section 1 From Genes to Proteins Translation: Assembling Proteins
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)
TranslationRNA 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.
TranslationRNA 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
Chapter 10 Section 1 From Genes to Proteins Translation: Forming the First Peptide Bond
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
Chapter 10 Section 1 From Genes to Proteins Translation: Assembling Proteins
Video showing transcription/translation • https://www.youtube.com/watch?v=erOP76_qLWA
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 mutations 1. Point mutation- affects one nucleotide 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 mutation B. 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 • Hegogranouthheb 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. • Thedogran down the street. • The cat ate a bird. • The dog ate a bird. Still makes “sense”.