1. Concepts and Applications Eighth Edition
Powerpoint Lecture Outline
Human Genetics
Concepts and Applications
Eighth Edition
Ricki Lewis
Prepared by
Dubear Kroening
University of Wisconsin-Fox Valley

2. Chapter 11 Control of Gene Expression and Genome Architecture

3. Gene Expression Over Time
Changes in gene expression may occur over time
This may occur at the molecular, tissue, or organ gland level
May be a response to environment

4. Globin Chain Switching
Adult hemoglobin has four polypeptide chains
Genes for alpha and beta subunits are located on chromosome 11 and 16 respectively
Subunits change in response to oxygen levels
Subunit makeup varies between embryo, fetus, and adult

5. Hemoglobin Composed of: Globular proteins
Two alpha chains and two beta chains
They surround an iron-containing heme group
Figure 11.1

6. Globin Chain Switching
Figure 11.2

7. Changing Gene Expression in Blood Plasma
Blood plasma contains 40,000 different types of protein
Changing conditions cause a change in the protein profile of the plasma
Stem cell biology is beginning to shed light on how genes are turned on and off

8. Pancreas Exocrine and endocrine function
Differential gene expression produces either endocrine or exocrine cells
If transcription factor pdx-1 is activated, some progenitor cells follow the exocrine pathway
Figure 11.3

9. Table 11.1

10. Differential Gene Expression
Figure 11.4

11. Proteomics
Uses analytical chemistry and microarrays to study all proteins produced
Fourteen categories of proteins
Variation in gene expression over lifespan and environment

12. Figure 11.5

13. Mechanisms of Gene Expression
Transcription factors
Promoter sequences (mutations)
Copies of genes
Histone code
Histones play a major role in exposing DNA for transcription
Important molecules: acetyl groups, methyl groups, and phosphates

14. Control of DNA Expression
Figure 11.7

15. RNA Interference (RNAi)
Transcription from DNA strand complementary to gene, bind to mRNA complements targeting them for removal
Promotes gene silencing in the nucleus by methylating histones
Removes certain mRNAs in the cytoplasm
Biotechnology – gene “knock-down”

16. Figure 11.10

17. Figure 11.11

18. Proteins Outnumber Genes
1.5% of human genome encodes protein
25,000 genes specify up to 200,000 proteins
Alternative splicing and cutting proteins translated from a single gene

19. Alternative Splicing within a Gene
Figure 11.12

20. Dentinogenesis imperfecta
Figure 11.13a
Caused by deficiency in proteins DPP and DSP
Both are cut from same larger protein

21. DPP and DSP
Figure 11.13b

22. Majority of Human Genome Does not Encode Protein
Rest of genome encodes for
Viral DNA
Noncoding RNAs
Introns
Promoters
Other controls
Repeats – transposons, telomeres, centromeres, pseudogenes, others

23. Table 11.4

24. Many companies are offering products based on RNA interference to use in research to "knock down" gene expression.
Go to one of the following websites for the following companies, or find others.
Research a particular RNAi product, and suggest how it might be used. (The companies listed have all existed for many years. There are many newer ones.)
Ambion
Invitrogen
New England Biolabs
Novagen
Qiagen
Stratagene