Your SlideShare is downloading. ×
0
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. regulator gene promoter opera...
Outline <ul><li>Prokaryotic Regulation </li></ul><ul><ul><li>trp Operon </li></ul></ul><ul><ul><li>lac Operon </li></ul></...
Prokaryotic Regulation <ul><li>Bacteria do not require the same enzymes all the time </li></ul><ul><li>Enzymes are produce...
Prokaryotic Regulation: The Operon Model <ul><li>Operon consist of three components </li></ul><ul><ul><li>Promoter </li></...
Animation Please note that due to differing operating systems, some animations will not appear until the presentation is v...
Repressible Operons: The trp Operon <ul><li>The regulator codes for a repressor  </li></ul><ul><li>If tryptophan (an amino...
Animation Please note that due to differing operating systems, some animations will not appear until the presentation is v...
The trp Operon Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. When the repre...
The trp Operon Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. regulator gene...
Inducible Operons: The lac Operon <ul><li>The regulator codes for a repressor  </li></ul><ul><li>If lactose (a sugar that ...
Animation Please note that due to differing operating systems, some animations will not appear until the presentation is v...
The lac Operon Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. regulator gene...
Animation Please note that due to differing operating systems, some animations will not appear until the presentation is v...
Action of CAP Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. DNA inactive CA...
Animation Please note that due to differing operating systems, some animations will not appear until the presentation is v...
Eukaryotic Regulation <ul><li>A variety of mechanisms </li></ul><ul><li>Five primary levels of control: </li></ul><ul><ul>...
Animation Please note that due to differing operating systems, some animations will not appear until the presentation is v...
Regulation of Gene Expression: Levels of Control in Eukaryotes functional protein plasma membrane polypeptide chain Posttr...
Chromatin Structure <ul><li>Eukaryotic DNA associated with histone proteins  </li></ul><ul><ul><li>Together make up chroma...
Chromatin Structure Regulates  Gene Expression Copyright © The McGraw-Hill Companies, Inc. Permission required for reprodu...
Chromatin Packing <ul><li>Euchromatin </li></ul><ul><ul><li>Loosely coiled DNA </li></ul></ul><ul><ul><li>Transcriptionall...
X-Inactivation in Mammalian Females Coats of tortoiseshell cats have patches of orange and black. One X chromosome is inac...
Transcriptional Control <ul><li>Transcription controlled by proteins called transcription factors </li></ul><ul><ul><li>Bi...
Animation Please note that due to differing operating systems, some animations will not appear until the presentation is v...
Animation Please note that due to differing operating systems, some animations will not appear until the presentation is v...
Animation Please note that due to differing operating systems, some animations will not appear until the presentation is v...
Eukaryotic Transcription Factors Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or displ...
Posttranscriptional Control <ul><li>Posttranscriptional control operates on primary mRNA transcript </li></ul><ul><li>Give...
Processing of mRNA Transcripts Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display...
Function of microRNAs Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. pre-mRN...
Translational Control <ul><li>Translational Control - Determines degree to which mRNA is translated into a protein product...
Regulation Through Gene Mutation <ul><li>Mutation is a permanent change in the sequence of bases in DNA.  </li></ul><ul><u...
Causes of Mutations <ul><li>Spontaneous mutation  </li></ul><ul><ul><li>DNA can undergo a chemical change </li></ul></ul><...
Animation Please note that due to differing operating systems, some animations will not appear until the presentation is v...
The Ames Test For Mutagenicity bacterial strain (requires histidine) Control Mutation did not occur Mutation occurred Susp...
Causes of Mutations <ul><li>Ultraviolet (UV) radiation is easily absorbed by the pyrimidines in DNA. </li></ul><ul><li>Cau...
Causes of Mutations <ul><li>Usually, these dimers are removed by  DNA repair enzymes </li></ul><ul><ul><li>Deficient DNA r...
Animation Please note that due to differing operating systems, some animations will not appear until the presentation is v...
XerodermaPigmentosome Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. © Ken G...
Effect of Mutations on Protein Activity <ul><li>Point Mutations  </li></ul><ul><ul><li>Involve change in a single DNA nucl...
Point Mutations in Hemoglobin Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display....
Carcinogenesis <ul><li>Development of cancer involves a series of mutations </li></ul><ul><li>Proto-oncogenes – Stimulate ...
Cell Signaling Pathway <ul><li>Cell signaling pathway that stimulates a mutated tumor suppressor gene </li></ul>Copyright ...
Cell Signaling Pathway <ul><li>Cell signaling pathway that stimulates a proto-oncogene </li></ul>Copyright © The McGraw-Hi...
Review <ul><li>Prokaryotic Regulation </li></ul><ul><ul><li>trp Operon </li></ul></ul><ul><ul><li>lac Operon </li></ul></u...
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. regulator gene promoter opera...
Upcoming SlideShare
Loading in...5
×

13 Lecture Animation Ppt

11,093

Published on

bio101

Published in: Technology
2 Comments
2 Likes
Statistics
Notes
  • hi sir
    Animationa are not running.Plz help.
       Reply 
    Are you sure you want to  Yes  No
    Your message goes here
  • Hello sir
    Introduce myself as a senior lecturer working in TP, Singapore, Animations used in your power point slides are excellent. Would like to use your slides to teach my students and also request your permission to be used by my students on their computers to learn the topic on mutation. So could you please grant me permission to use yoru slides with animation.
    Thank you very much
    regards
    DR.R.Raja
       Reply 
    Are you sure you want to  Yes  No
    Your message goes here
No Downloads
Views
Total Views
11,093
On Slideshare
0
From Embeds
0
Number of Embeds
2
Actions
Shares
0
Downloads
1,195
Comments
2
Likes
2
Embeds 0
No embeds

No notes for slide
  • Biology, 9th ed,Sylvia Mader Gene Regulation Slide # Chapter 15
  • Biology, 9th ed,Sylvia Mader Gene Regulation Slide # Chapter 15
  • Transcript of "13 Lecture Animation Ppt"

    1. 1. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. regulator gene promoter operator structural genes DNA RNA polymerase RNA polymerase cannot bind to promoter. mRNA enzymes inactive repressor a. Tryptophan absent. Enzymes needed to synthesize tryptophan are produced. DNA inactive repressor b. Tryptophan present. Presence of tryptophan prevents production of enzymes used to synthesize tryptophan. tryptophan active repressor 5  3 
    2. 2. Outline <ul><li>Prokaryotic Regulation </li></ul><ul><ul><li>trp Operon </li></ul></ul><ul><ul><li>lac Operon </li></ul></ul><ul><li>Eukaryotic Regulation </li></ul><ul><ul><li>Chromatin Structure </li></ul></ul><ul><ul><li>Transcriptional Control </li></ul></ul><ul><ul><li>Posttranscriptional Control </li></ul></ul><ul><ul><li>Translational Control </li></ul></ul><ul><ul><li>Posttranslational Control </li></ul></ul><ul><li>Genetic Mutations </li></ul><ul><ul><li>Cancer </li></ul></ul>
    3. 3. Prokaryotic Regulation <ul><li>Bacteria do not require the same enzymes all the time </li></ul><ul><li>Enzymes are produced as needed </li></ul><ul><li>Francois Jacob and Jacques Monod (1961) proposed the operon model to explain regulation of gene expression in prokaryotes </li></ul><ul><li>Operon is a group of structural and regulatory genes that function as a single unit </li></ul>
    4. 4. Prokaryotic Regulation: The Operon Model <ul><li>Operon consist of three components </li></ul><ul><ul><li>Promoter </li></ul></ul><ul><ul><ul><li>DNA sequence where RNA polymerase first attaches </li></ul></ul></ul><ul><ul><ul><li>Short segment of DNA </li></ul></ul></ul><ul><ul><li>Operator </li></ul></ul><ul><ul><ul><li>DNA sequence where active repressor binds </li></ul></ul></ul><ul><ul><ul><li>Short segment of DNA </li></ul></ul></ul><ul><ul><li>Structural Genes </li></ul></ul><ul><ul><ul><li>One to several genes coding for enzymes of a metabolic pathway </li></ul></ul></ul><ul><ul><ul><li>Translated simultaneously as a block </li></ul></ul></ul><ul><ul><ul><li>Long segment of DNA </li></ul></ul></ul>
    5. 5. Animation Please note that due to differing operating systems, some animations will not appear until the presentation is viewed in Presentation Mode (Slide Show view). You may see blank slides in the “Normal” or “Slide Sorter” views. All animations will appear after viewing in Presentation Mode and playing each animation. Most animations will require the latest version of the Flash Player, which is available at http://get.adobe.com/flashplayer.
    6. 6. Repressible Operons: The trp Operon <ul><li>The regulator codes for a repressor </li></ul><ul><li>If tryptophan (an amino acid) is absent: </li></ul><ul><ul><li>Repressor is unable to attach to the operator (expression is normally “on”) </li></ul></ul><ul><ul><li>RNA polymerase binds to the promoter </li></ul></ul><ul><ul><li>Enzymes for synthesis of tryptophan are produced </li></ul></ul><ul><li>If tryptophan is present: </li></ul><ul><ul><li>Combines with repressor as corepressor </li></ul></ul><ul><ul><li>Repressor becomes functional </li></ul></ul><ul><ul><li>Blocks synthesis of enzymes and tryptophan </li></ul></ul>
    7. 7. Animation Please note that due to differing operating systems, some animations will not appear until the presentation is viewed in Presentation Mode (Slide Show view). You may see blank slides in the “Normal” or “Slide Sorter” views. All animations will appear after viewing in Presentation Mode and playing each animation. Most animations will require the latest version of the Flash Player, which is available at http://get.adobe.com/flashplayer.
    8. 8. The trp Operon Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. When the repressor binds to the operator, transcription is prevented. active repressor structural genes regulator gene promoter operator
    9. 9. The trp Operon Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. regulator gene promoter operator structural genes DNA RNA polymerase RNA polymerase cannot bind to promoter. mRNA enzymes inactive repressor a. Tryptophan absent. Enzymes needed to synthesize tryptophan are produced. DNA inactive repressor b. Tryptophan present. Presence of tryptophan prevents production of enzymes used to synthesize tryptophan. tryptophan active repressor 5  3 
    10. 10. Inducible Operons: The lac Operon <ul><li>The regulator codes for a repressor </li></ul><ul><li>If lactose (a sugar that can be used for food) is absent: </li></ul><ul><ul><li>Repressor attaches to the operator </li></ul></ul><ul><ul><li>Expression is normally “off” </li></ul></ul><ul><li>If lactose is present: </li></ul><ul><ul><li>It combines with repressor and renders it unable to bind to operator </li></ul></ul><ul><ul><li>RNA polymerase binds to the promoter </li></ul></ul><ul><ul><li>The three enzymes necessary for lactose catabolism are produced </li></ul></ul>
    11. 11. Animation Please note that due to differing operating systems, some animations will not appear until the presentation is viewed in Presentation Mode (Slide Show view). You may see blank slides in the “Normal” or “Slide Sorter” views. All animations will appear after viewing in Presentation Mode and playing each animation. Most animations will require the latest version of the Flash Player, which is available at http://get.adobe.com/flashplayer.
    12. 12. The lac Operon Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. regulator gene promoter operator structural genes DNA RNA polymerase cannot bind to promoter. RNA polymerase can bind to promoter. active repressor active repressor mRNA enzymes active repressor inactive repressor b. Lactose present. Enzymes needed to take up and use lactose are produced only when lactose is present. a. Lactose absent. Enzymes needed to take up and use lactose are not produced. lactose DNA 5  3 
    13. 13. Animation Please note that due to differing operating systems, some animations will not appear until the presentation is viewed in Presentation Mode (Slide Show view). You may see blank slides in the “Normal” or “Slide Sorter” views. All animations will appear after viewing in Presentation Mode and playing each animation. Most animations will require the latest version of the Flash Player, which is available at http://get.adobe.com/flashplayer.
    14. 14. Action of CAP Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. DNA inactive CAP inactive CAP active CAP a. Lactose present, glucose absent (cAMP level high) b. Lactose present, glucose present (cAMP level low) DNA cAMP promoter CAP binding site RNA polymerase binds fully with promoter. RNA polymerase does not bind fully with promoter. promoter operator operator CAP binding site
    15. 15. Animation Please note that due to differing operating systems, some animations will not appear until the presentation is viewed in Presentation Mode (Slide Show view). You may see blank slides in the “Normal” or “Slide Sorter” views. All animations will appear after viewing in Presentation Mode and playing each animation. Most animations will require the latest version of the Flash Player, which is available at http://get.adobe.com/flashplayer.
    16. 16. Eukaryotic Regulation <ul><li>A variety of mechanisms </li></ul><ul><li>Five primary levels of control: </li></ul><ul><ul><li>Nuclear levels </li></ul></ul><ul><ul><ul><li>Chromatin Packing </li></ul></ul></ul><ul><ul><ul><li>Transcriptional Control </li></ul></ul></ul><ul><ul><ul><li>Posttranscriptional Control </li></ul></ul></ul><ul><ul><li>Cytoplasmic levels </li></ul></ul><ul><ul><ul><li>Translational Control </li></ul></ul></ul><ul><ul><ul><li>Posttranslational Control </li></ul></ul></ul>
    17. 17. Animation Please note that due to differing operating systems, some animations will not appear until the presentation is viewed in Presentation Mode (Slide Show view). You may see blank slides in the “Normal” or “Slide Sorter” views. All animations will appear after viewing in Presentation Mode and playing each animation. Most animations will require the latest version of the Flash Player, which is available at http://get.adobe.com/flashplayer.
    18. 18. Regulation of Gene Expression: Levels of Control in Eukaryotes functional protein plasma membrane polypeptide chain Posttranslational control Posttranscriptional control Transcriptional control Translational control nuclear pore mRNA pre- mRNA intron exon histones nuclear envelope Chromatin structure Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 3  5  3  5 
    19. 19. Chromatin Structure <ul><li>Eukaryotic DNA associated with histone proteins </li></ul><ul><ul><li>Together make up chromatin </li></ul></ul><ul><ul><li>As seen in the interphase nucleus </li></ul></ul><ul><li>Nucleosomes: </li></ul><ul><ul><li>DNA wound around balls of eight molecules of histone proteins </li></ul></ul><ul><ul><li>Looks like beads on a string </li></ul></ul><ul><ul><li>Each bead a nucleosome </li></ul></ul><ul><li>The levels of chromatin packing determined by degree of nucleosome coiling </li></ul>
    20. 20. Chromatin Structure Regulates Gene Expression Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. DNA histone protein a. Darkly stained heterochromatin and lightly stained euchromatin b. A nucleosome c. DNA unpacking H2A H2B H3 H1 H4 histone tail nucleosome accessible promoter DNA to be transcribed inaccessible promoter a: Courtesy Stephen Wolfe euchromatin heterochromatin nucleolus 1  m chromatin remodeling complex
    21. 21. Chromatin Packing <ul><li>Euchromatin </li></ul><ul><ul><li>Loosely coiled DNA </li></ul></ul><ul><ul><li>Transcriptionally active </li></ul></ul><ul><li>Heterochromatin </li></ul><ul><ul><li>Tightly packed DNA </li></ul></ul><ul><ul><li>Transcriptionally inactive </li></ul></ul><ul><li>Barr Bodies </li></ul><ul><ul><li>Females have two X chromosomes, but only one is active </li></ul></ul><ul><ul><li>Other is tightly packed along its entire length </li></ul></ul><ul><ul><li>Inactive X chromosome is Barr body </li></ul></ul>
    22. 22. X-Inactivation in Mammalian Females Coats of tortoiseshell cats have patches of orange and black. One X chromosome is inactivated in each cell. Which one is by chance. Females have two X chromosomes. active X chromosome inactive X inactive X active X chromosome allele for orange color allele for black color cell division Barr bodies © Chanan Photo 2004 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
    23. 23. Transcriptional Control <ul><li>Transcription controlled by proteins called transcription factors </li></ul><ul><ul><li>Bind to enhancer DNA </li></ul></ul><ul><ul><li>Regions of DNA where factors that regulate transcription can also bind </li></ul></ul><ul><ul><li>Always present in cell, but most likely have to be activated before they will bind to DNA </li></ul></ul>
    24. 24. Animation Please note that due to differing operating systems, some animations will not appear until the presentation is viewed in Presentation Mode (Slide Show view). You may see blank slides in the “Normal” or “Slide Sorter” views. All animations will appear after viewing in Presentation Mode and playing each animation. Most animations will require the latest version of the Flash Player, which is available at http://get.adobe.com/flashplayer.
    25. 25. Animation Please note that due to differing operating systems, some animations will not appear until the presentation is viewed in Presentation Mode (Slide Show view). You may see blank slides in the “Normal” or “Slide Sorter” views. All animations will appear after viewing in Presentation Mode and playing each animation. Most animations will require the latest version of the Flash Player, which is available at http://get.adobe.com/flashplayer.
    26. 26. Animation Please note that due to differing operating systems, some animations will not appear until the presentation is viewed in Presentation Mode (Slide Show view). You may see blank slides in the “Normal” or “Slide Sorter” views. All animations will appear after viewing in Presentation Mode and playing each animation. Most animations will require the latest version of the Flash Player, which is available at http://get.adobe.com/flashplayer.
    27. 27. Eukaryotic Transcription Factors Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. promoter DNA enhancer transcription activator mediator proteins mRNA transcription RNA polymerase transcription factor complex gene
    28. 28. Posttranscriptional Control <ul><li>Posttranscriptional control operates on primary mRNA transcript </li></ul><ul><li>Given a specific primary transcript: </li></ul><ul><ul><li>Excision of introns can vary </li></ul></ul><ul><ul><li>Splicing of exons can vary </li></ul></ul><ul><ul><li>Determines the type of mature transcript that leaves the nucleus </li></ul></ul><ul><li>May also control speed of mRNA transport from nucleus to cytoplasm </li></ul><ul><ul><li>Will affect the number of transcripts arriving at rough ER </li></ul></ul><ul><ul><li>And therefore the amount of gene product realized per unit time </li></ul></ul>
    29. 29. Processing of mRNA Transcripts Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. intron intron intron cap protein product 1 mRNA RNA splicing poly-A tail exon intron protein product 2 RNA splicing exon a. b. cap A B C D E A B C D E A B C C D E A D E B pre-mRNA mRNA pre-mRNA poly-A tail 5  3  5  3 
    30. 30. Function of microRNAs Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. pre-mRNA MicroRNA is cut from a pre-mRNA and binds with proteins to form RISC. Complementary base pairing between RNAs allows RISC to bind to mRNA. Translation is inhibited. The mRNA is degraded. mRNA RISC (RNA-induced silencing complex) microRNA (miRNA) proteins or RISC 5  3  3  5  5  3 
    31. 31. Translational Control <ul><li>Translational Control - Determines degree to which mRNA is translated into a protein product </li></ul><ul><ul><li>Presence of 5′ cap </li></ul></ul><ul><ul><li>Length of poly-A tail on 3′ end </li></ul></ul><ul><li>Posttranslational Control - Affects the activity of a protein product </li></ul><ul><ul><li>Activation </li></ul></ul><ul><ul><li>Degradation rate </li></ul></ul>
    32. 32. Regulation Through Gene Mutation <ul><li>Mutation is a permanent change in the sequence of bases in DNA. </li></ul><ul><ul><li>No effect on protein activity </li></ul></ul><ul><ul><li>Protein is completely inactivated </li></ul></ul><ul><li>Germ-line mutations occur in sex cells </li></ul><ul><li>Somatic mutations occur in body cells </li></ul>
    33. 33. Causes of Mutations <ul><li>Spontaneous mutation </li></ul><ul><ul><li>DNA can undergo a chemical change </li></ul></ul><ul><ul><li>Movement of transposons from one chromosomal location to another </li></ul></ul><ul><ul><li>Replication Errors </li></ul></ul><ul><ul><ul><li>1 in 1,000,000,000 replications </li></ul></ul></ul><ul><ul><ul><li>DNA polymerase </li></ul></ul></ul><ul><ul><ul><ul><li>Proofreads new strands </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Generally corrects errors </li></ul></ul></ul></ul><ul><li>Induced mutation: </li></ul><ul><ul><li>Mutagens such as radiation, organic chemicals </li></ul></ul><ul><ul><li>Many mutagens are also carcinogens (cancer causing) </li></ul></ul><ul><ul><li>Environmental Mutagens </li></ul></ul><ul><ul><ul><li>Ultraviolet Radiation </li></ul></ul></ul><ul><ul><ul><li>Tobacco Smoke </li></ul></ul></ul>
    34. 34. Animation Please note that due to differing operating systems, some animations will not appear until the presentation is viewed in Presentation Mode (Slide Show view). You may see blank slides in the “Normal” or “Slide Sorter” views. All animations will appear after viewing in Presentation Mode and playing each animation. Most animations will require the latest version of the Flash Player, which is available at http://get.adobe.com/flashplayer.
    35. 35. The Ames Test For Mutagenicity bacterial strain (requires histidine) Control Mutation did not occur Mutation occurred Suspected chemical mutagen bacterial strain (requires histidine) Plate onto petri plates that lack histidine. Incubate overnight bacterial growth Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
    36. 36. Causes of Mutations <ul><li>Ultraviolet (UV) radiation is easily absorbed by the pyrimidines in DNA. </li></ul><ul><li>Cause neighboring thymine molecules next to one another to bond together </li></ul><ul><ul><li>Thymine dimers . </li></ul></ul>C G C A A G kink thymine dimer Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. T T
    37. 37. Causes of Mutations <ul><li>Usually, these dimers are removed by DNA repair enzymes </li></ul><ul><ul><li>Deficient DNA repair enzymes leave the skin cells vulnerable to the mutagenic effects of ultraviolet light </li></ul></ul><ul><ul><ul><li>Accumulation of mutation </li></ul></ul></ul><ul><ul><ul><li>High incidence of cancer </li></ul></ul></ul>
    38. 38. Animation Please note that due to differing operating systems, some animations will not appear until the presentation is viewed in Presentation Mode (Slide Show view). You may see blank slides in the “Normal” or “Slide Sorter” views. All animations will appear after viewing in Presentation Mode and playing each animation. Most animations will require the latest version of the Flash Player, which is available at http://get.adobe.com/flashplayer.
    39. 39. XerodermaPigmentosome Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. © Ken Greer/Visuals Unlimited
    40. 40. Effect of Mutations on Protein Activity <ul><li>Point Mutations </li></ul><ul><ul><li>Involve change in a single DNA nucleotide </li></ul></ul><ul><ul><li>Changes one codon to a different codon </li></ul></ul><ul><ul><li>Affects on protein vary: </li></ul></ul><ul><ul><ul><li>Nonfunctional </li></ul></ul></ul><ul><ul><ul><li>Reduced functionality </li></ul></ul></ul><ul><ul><ul><li>Unaffected </li></ul></ul></ul><ul><li>Frameshift Mutations </li></ul><ul><ul><li>One or two nucleotides are either inserted or deleted from DNA </li></ul></ul><ul><ul><li>Protein always rendered nonfunctional </li></ul></ul><ul><ul><ul><li>Normal : THE CAT ATE THE RAT </li></ul></ul></ul><ul><ul><ul><li>After deletion: THE ATA TET HER AT </li></ul></ul></ul><ul><ul><ul><li>After insertion: THE CCA TAT ETH ERA T </li></ul></ul></ul>
    41. 41. Point Mutations in Hemoglobin Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. b. Normal red blood cell a. c. Sickled red blood cell No mutation Val His Leu Thr Pro Glu Glu (normal protein) His His (abnormal protein) Glu Val (incomplete protein) Glu Stop C T C C T C T G G A G T C A C G T G G A G C T C C T C T G G A G T C A C G T G A G Val His Leu Thr Pro Glu Glu C T C C A C T G G A G T C A C G T G G A G Val His Leu Thr Pro Glu C T C C A T G G A G T C A C G T G G A G T Val His Leu Thr Pro Stop A b, c: © Stan Flegler/Visuals Unlimited. Val 3  5 
    42. 42. Carcinogenesis <ul><li>Development of cancer involves a series of mutations </li></ul><ul><li>Proto-oncogenes – Stimulate cell cycle </li></ul><ul><li>Tumor suppressor genes – inhibit cell cycle </li></ul><ul><li>Mutation in oncogene and tumor suppressor gene: </li></ul><ul><ul><ul><li>Stimulates cell cycle uncontrollably </li></ul></ul></ul><ul><ul><ul><li>Leads to tumor formation </li></ul></ul></ul>
    43. 43. Cell Signaling Pathway <ul><li>Cell signaling pathway that stimulates a mutated tumor suppressor gene </li></ul>Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. receptor inhibiting growth factor cytoplasm plasma membrane signal transducers transcription factor nucleus protein that is unable to inhibit the cell cycle or promote apoptosis mutated tumor suppressor gene
    44. 44. Cell Signaling Pathway <ul><li>Cell signaling pathway that stimulates a proto-oncogene </li></ul>Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. receptor stimulating growth factor cytoplasm plasma membrane signal transducers transcription factor nucleus protein that overstimulates the cell cycle oncogene
    45. 45. Review <ul><li>Prokaryotic Regulation </li></ul><ul><ul><li>trp Operon </li></ul></ul><ul><ul><li>lac Operon </li></ul></ul><ul><li>Eukaryotic Regulation </li></ul><ul><ul><li>Transcriptional Control </li></ul></ul><ul><ul><li>Posttranscriptional Control </li></ul></ul><ul><ul><li>Translational Control </li></ul></ul><ul><ul><li>Posttranslational Control </li></ul></ul><ul><li>Genetic Mutations </li></ul><ul><ul><li>Cancer </li></ul></ul>
    46. 46. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. regulator gene promoter operator structural genes DNA RNA polymerase RNA polymerase cannot bind to promoter. mRNA enzymes inactive repressor a. Tryptophan absent. Enzymes needed to synthesize tryptophan are produced. DNA inactive repressor b. Tryptophan present. Presence of tryptophan prevents production of enzymes used to synthesize tryptophan. tryptophan active repressor 5  3 
    1. A particular slide catching your eye?

      Clipping is a handy way to collect important slides you want to go back to later.

    ×