Animations http://highered.mcgraw-hill.com/olc/dl/120077/micro06.swf Home: http://highered.mcgraw-hill.com/sites/dl/free/0072437316/120060/ravenanimation.html

Figure 17.0 Ribosome

Gene 1 gene (DNA) → 1 polypeptide (protein) 1 gene = 100s-1000s nucleotide pairs

Nucleic Acid Language (G.C.T.A.) ≠ Protein Language (20 Amino acids) Gene Nucleic Acid Language (G.C.T.A.) ≠ Protein Language (20 Amino acids)

The triplet code

Transcription & translation within cells Prokaryotic vs. Eukaryotic

20 amino acids for proteins: nonpolar polar ionic

“Universal dictionary” of the genetic code Few Exceptions: 1. Mitochondrial DNA 2. Chloroplast DNA 3. Some single-celled organisms

Codons same across most life☺

Tobacco plant w/ firefly gene Codons same across most life☺ Tobacco plant w/ firefly gene

Transgenic Coho Salmon (1 yr. old ) non-transgenic Source: Fisheries and Oceans Canada http://www.oag-bvg.gc.ca/internet/English/att_c20041006pe04_e_13393.html

GloFish® ??? Before & After: http://www.youtube.com/watch?v=FpGdGTUuodw [Zebra fish (Danio rerio)]

Stages of Transcription 1. Initiation 2. Elongation 3. Termination RNA polymerase

Initiation at a eukaryotic promoter

Elongation 60 nucleotides/sec. Termination pre-mRNA

RNA processing; addition of the 5 cap and poly(A) tail

RNA processing: RNA splicing

The roles of snRNPs and spliceosomes in mRNA splicing “Snurps” (& Ribozymes)

Alternative RNA splicing: (multiple genes may be stored in single DNA sequence) * Spiced differently = two meanings 1,2 * THREAANCADTCAJTKE 1 THREAANCADTCAJTKE 2 THREAANCADTCAJTKE

Alternative RNA splicing: (multiple genes may be stored in single DNA sequence) * Spiced differently = two meanings 1,2 * THREAANCADTCAJTKE 1 THREAANCADTCAJTKE 2 THREAANCADTCAJTKE

Alternative RNA splicing: (multiple genes may be stored in single DNA sequence) * Spiced differently = two meanings 1,2 * THREAANCADTCAJTKE “THE- CAT – ATE” 1 THREAANCADTCAJTKE “TEA - AND – CAKE” 2 THREAANCADTCAJTKE

Alternative RNA splicing: (multiple genes may be stored in single DNA sequence) * Spiced differently = two meanings 1,2 * THREAANCADTCAJTKE “THE- CAT – ATE” 1 THREAANCADTCAJTKE “TEA - AND – CAKE” 2 THREAANCADTCAJTKE

Alternative RNA splicing: (multiple genes may be stored in single DNA sequence) * Spiced differently = two meanings 1,2 * THREAANCADTCAJTKE “THE- CAT – ATE” 1 THREAANCADTCAJTKE “TEA - AND – CAKE” 2 THREAANCADTCAJTKE

Spliceosomes http://highered.mcgraw-hill.com/olc/dl/120077/bio30.swf

Hypothesis: Domain: specific function of an exon Hypothesis: Domain: specific function of an exon *may explain source novel proteins

The nucleus & its envelope

Translation: the basic concept

Codon/A.A. dictionary

The structure of transfer RNA (tRNA)

The structure of transfer RNA (tRNA) 80 nucleotides

Aminoacyl-tRNA synthetase: joins amino acid & tRNA

61 codons have only 45 anticodons How? recognizes 2+ codons

third position of a codon. tRNA “Wobble” Nitrogenous base I (pairs with U, C, A) Nitrogenous base U (pairs with A, G) * Wobble only occurs in third position of a codon.

Activated A.A.

The anatomy of a functioning ribosome

Ribosome and Protein Production Steps: 1) Initiation 2) Elongation 3) Termination Each step requires Protein Factors

Initiation of translation

Elongation of translation

Termination of translation

Video of Ribosome & polypeptide synthesis http://highered.mcgraw-hill.com/olc/dl/120077/micro06.swf

Polyribosomes: Quick & Massive Protein Production

Video protein synthesis in Prokaryote & Eukaryotes http://highered.mcgraw-hill.com/olc/dl/120077/bio25.swf (Optional in class)

Review: the four levels of protein structure

A chaperonin in action

Post-translational structure changes: Chemical modification Removal of some A.A Cut/splice Polypeptide Multiple polypeptides mixed

“FREE” to “Bound” Ribosome: Signal mechanism (SRP) for targeting proteins to the ER, etc.

Bound Ribosomes: The nucleus, its envelope, & ER also Chloroplasts, Mitochondria, other organelles

Ribosomes: Free & Bound

Endoplasmic reticulum (ER)

Golgi apparatus

Types of RNA in a Eukaryotic Cell Diverse functions of RNA: Informational Structural Catalytic

Bacterial Protein Production: Coupled transcription and translation Animation: http://highered.mcgraw-hill.com/olc/dl/120077/bio25.swf

Mutations http://eyemakeart.files.wordpress.com/2009/07/eye_colour_chart_by_delpigeon.jpg http://media.photobucket.com/image/collage/KatyChoirGrl05/Collages/EyeCollage.png?o=398

Mutations: A change in genetic sequence (in DNA).

Mutations: A change in genetic sequence (in DNA). Types: 1. Base-pair substitution 2. Base Pair insertion/deletion

Mutations: A change in genetic sequence (in DNA) Mutations: A change in genetic sequence (in DNA). Point Mutation: one nucleotide pair changed

e.g. sickle-cell disease: point mutation (e.g. Base-pair substitution)

Base-pair substitution

Base-pair insertion or deletion “FRAMESHIFT” THE / CAR / AND / MAN / … THE / CAP / RAN / DMA / N… THE / CAR / AND / MAN / … HEC / ARA / NDM / AN. / …

Causes of Errors (Mutations) DNA Replication Repair Recombination Mutagens: - X-rays, UV, Chemicals, ….

Gametes! Where must mutations occur for a gene to be passed to future generations? Gametes!

A summary of transcription and translation in a eukaryotic cell

End: Protein Synthesis End of Material for Test 2 Go to Next Chapter

Nuclei and F-actin in BPAEC cells

Veterans Day / Armistice Day World War I ends: Nov. 11, 1918 at 11 am

Last female WWI vet dies at 109 Charlotte Winters (Nov 10,1897- Mar 27, 2007) Boonsboro, Maryland Typical female yeoman uniform, however, this is not Mrs. Winters.

Last Navy vet of WWI dies at 105 Lloyd Brown (October 7 1901- March 29, 2007) Charlotte Hall, MD