10 February 2003

Mid course correction forms due today; results on Wednesday

Second mid term exam Friday of next week; practice exam this Friday

 Need seniors

for chapter 8 we will look at proteins/ genes/ metabolic disorders in our species

For PKU: excellent presentation in form of text and visual/verbal presentation of two days of lectures: http://consensus.nih.gov/cons/113/113_intro.htm of importance: that which was thought to be a simple trait has turned out to be very complex (surprised?). Some of this complexity will be seen at the end of the course. .... For PKU please read description in the text...... fits into the ideas presented by Garrod a long time ago.

Chapter 8 Gene control of proteins as the gene product

First, the question of what do genes do.

Early work of George Beadle (corn geneticist, moved to Drosophila (in Morgan's lab, and then to Neurospora.

Beadle and Tatum picture..(not on web)... BeadleTatum-1958-1.GIF

Work on transplanting tissue in Drosophila: BeadleDrosophila.gif

one gene one enzyme hypothesis; Garrod (Inborn Errors of Metabolism), Beadle and Tatum

Neurospora life cycle...somatic nuclei haploid... neurospora1.GIF

Historical perspective: Perkins, D. D. (1992). "Neurospora: the organism behind the molecular revolution." Genetics 130(4): 687-701. "In Japan, Neurospora made a dramatic apearance following the great Tokyo earthquake and fire of 1923"

Two types of media: Complete and minimal.....NeurosporaMedia.GIF

protocol for experiments...BeadleTatum1.GIF

BeadleTatum2.GIF

Results... Table 8.1 and Figure 8.3

For arginine and intermediate compounds ...... Neurospora.gif

Location of mutations and pathways ....08x3.gif

 

idea: One gene one enzyme; has undergone several modifications, as one gene one polypeptide, one gene one function, one gene more than one polypeptide.

Work of Garrod...Inborn errors of metabolism; work on four traits: albinism, alkaptonuria, cyctinuria, pentosuria

picture..(not on web)...Garrod

As Fig 8.1.... GarrodAlkaptonuria.gif

MORE ....1902 paper via web..http://www.esp.org/foundations/genetics/classical/ag-02.pdf

 

We will use hemoglobin as a model for various aspects of molecular genetics.

Information is provided in the form of the hemoglobin sheet, handed out today.

It is also available on the web via: ... betaglobin.pdf

protein structure (discussed again in chapter 13)

Overview

List of amino acids..page 282; and on hemoglobin sheet

Degrees of complexity (Fig 13.4)

Primary structure

Secondary structure

Tertiary structure

Quaternary structure

 

Proteins and mutations

Example, alpha and beta globin: .. AminoAcidSeqs.GIF

Sickle cell anemia..

Hb S mutation and pleiotrophic effects..... Pleiotrophy.gif

Gel electrophoresis (not on web).. Electrophoresis.gif

as Figure 8.5 in text.. 05.gif

Quartenary structure of hemoglobin ... Figure 8.6 .. 06.gif

First seven amino acids ... Figure 8.7 ... 07.gif

protein function; human diseases

see Table 8.2 for list of inborn errors of metabolism

similar table on the web .... http://www.ncbi.nlm.nih.gov:80/books/bv.fcgi?call=bv.View..ShowSection&rid=iga.table.d1e36589

also hemoglobin mutants, ABO antigens, Cystic fibrosis, genetic counseling

OHSU laboratory: ...Biochemical Genetics Laboratory

Modification: One gene one protein; and idea eventually falls apart.

Structure of proteins

Pauling.gif

Detection of abnormalities via amniocentesis

see Figures 8.10 and 8.11

 

To chapter 9... Chapter09.html