Einführung in die Genetik

Prof. Dr. Kay Schneitz (EBio Pflanzen)http://plantdev.bio.wzw.tum.deschneitz@wzw.tum.de

Prof. Dr. Claus Schwechheimer (PlaSysBiol)http://wzw.tum.de/sysbiolclaus.schwechheimer@wzw.tum.de

Übung zur Genetikvorlesung (HS 17)

09.03. - 13.03.9.00 h - 16.00 h

Tutorium zur Übung (HS 17)14.03.

9.00 h -

Gemeinsame Klausur VL und Übung (HS 14)14.03.

13.00 h - 14.30 h

Einführung in die Genetik - InhalteEinführung in die Genetik - InhalteEinführung in die Genetik - Inhalte1 Einführung 15. 10. 13 KS2 Struktur von Genen und Chromosomen 22. 10. 13 KS3 Genfunktion 29. 10. 13 KS4 Transmission der DNA während der Zellteilung 05. 11. 13 KS5 Vererbung von Einzelgenveränderungen 12. 11. 13 KS6 Genetische Rekombination (Eukaryonten) 19. 11. 13 KS7 Genetische Rekombination (Bakterien/Viren) 26. 11. 13 KS8 Rekombinante DNA-Technologie 03. 12. 13 CS9 Kartierung/Charakterisierung ganzer Genome 10. 12. 13 CS

10 Genmutationen: Ursache und Reparatur 17. 12. 13 CS11 Veränderungen der Chromosomen 07. 01. 14 CS12 Genetische Analyse biologischer Prozesse 14. 01. 14 CS13 Transposons bei Eukaryonten 21. 01. 14 CS14 Regulation der Zellzahl 28. 01. 14 CS15 Regulation der Genexpression 04. 02. 14 KS

Genetic analysisGenetics 12

Based on Chapter 4 (9th or10th ed.)

Summary • Model organisms

• Genetic screen vs. genetic selection

• Choice of the mutagen

• Types of mutations (amorph, hypomorph, hypermorph, neomorph)

• Recombination and linkage (gene order, recombination frequency, cM, M.U.)

• Test crosses (concept of the tester)

• Phenotypic markers

• Molecular markers (SNPs, RFLP, mini- and microsatellites)

• Insertional mutagenesis (forward genetics)

Figure 4-8

For linked genes, recombinant frequencies areless than 50 percent

Transposons in eukaryotesGenetics 13

Based on Chapter 16 (10th ed.) or Chapter 14 (9th edition)

Structure of transposons

Class II: DNA Transposons

Transposons and genome evolution

Discovery of transposons

Class I: Retrotransposons

Discovery of transposons

The maize laboratory of Rollins A. Emerson at Cornell University

Model Organism: Maize

Analysis of maize chromosomes

The Ds transposable element helps cause breakage

Figure 14-2

Unusual phenotypes are caused by theDs transposable element

Figure 14-3a

Unusual phenotypes are caused by theDs transposable element

Figure 14-3b

Phenotypes produced by transposable elementsin corn kernels

Figure 14-4

Structure of transposons

Structural features of composite and simple transposons

Figure 14-6

Figure 14-7

An R plasmid may contain several transposonscarrying resistance genes

An inserted element is flanked by a short repeat

Figure 14-8

Two modes of transposition

Figure 14-9

Replicative transposition of Tn3

Figure 14-10

Class I: Retrotransposons

Life cycle of a retrovirus

Figure 14-11

Retrotransposons have features in common with retroviruses

Figure 14-12

A retrotransposon is transposed through an RNA intermediate

Figure 14-13

Demonstration of transposition through an RNA intermediate

Figure 14-14

Class II: DNA transposons

P-element structure

Figure 14-16

Hybrid dysgenesis in Drosophila led to the discovery of P elements

Figure 14-15

Figure 14-17

Insertion of P elements causes the mutations underlying hybrid dysgenesis

P elements can be engineered to transfer genes- Transposon tagging -

Figure 14-19

Activator transposase catalyzes excision and integration

Transposable elements at work in snapdragon

Figure 14-5

Transposons and genome evolution

Types of transposable elements in the human genome

Figure 14-20

LINE long interspersed elementSINE short interspersed element

Human genes contain many transposable elements

Figure 14-21

Transposable elements in grasses are responsible fordifferences in genome size

Figure 14-22

Transposable elements insert into “safe havens”

Figure 14-23a

Transposable elements insert into safe havens

Figure 14-23b

What you need to know and understand for

the exam and for your life....

... composite transposons, simple transposons

... transposons and resistance genes

...replicative and conservative transposition

...structure of retrotransposons (gag, pol, env)

...RNA-origin of retrotransposons (intron splicing)

...DNA transposons

...DNA transposons in the human genome (LINE, SINE, Alu)

...Ac/Ds transposons, P elements

...safe havens

The end