Waterborg's Chromatin HomePage

Chromatin

START a slide presentation that explores key concepts and papers:
• Nuclear packaging of DNA: chromosome structure and DNA domains
• Nucleosome structure: core histones assemble to package 145 bp of DNA
• Chromatin fibers: structure and stabilizing forces
• Histone acetylation: how does it work
• Gel analysis of histones: SDS, Acid Urea and Acid Urea Triton gel separation
• Acetylation and Deacetylation: activate or repress chromatin transcription, at promoters and across chromatin domains
• How is chromatin transcribed? : models and the role of Replacement Histone H3
  
  
  Phylogenesis of Histone H3
  
  Measuring Dynamic Histone Acetylation in vivo, a lecture for the Karolinska, 2002.
  A description of experimental methodologies and results for histone acetylation turnover of histones H3 and H4 in Chlamydomonas reinhardtii and Saccharomyces cerevisiae.
• January 2002: Powerpoint presentation for Internet Explorer version 4+ on 17"+ monitor). This presentation will not run in a Netscape (version 4.7x) browser.
• Browse the slides (without animation) with lecture notes in a frame, or:
• Click the 'slide show' icon for full-screen slides with animation (click the mouse to proceed).
  Colleagues in the chromatin field: you are allowed to download the full powerpoint presentation provided that the "© 2002 Waterborg - UMKC" notice is retained (7.4 MB file).
  • In Internet Explorer, right-click and select "Save Target As..."
  • In Netscape, hold Shift Key and click the link.
• A videotape of this lecture has been produced on VHS.
  A high-resulution version of this lecture with all audio can be downloaded as a zip file of 188 MB !! (sic). It contains the complete PowerPoint 2000 presentation and all digitized audio of the recorded lecture linked to automatic in-slide animation.
  • In Internet Explorer, right-click and select "Save Target As..."
  • In Netscape, hold Shift Key and click the link.
  
  
  
• Dynamic Histone Acetylation in yeast Saccharomyces cerevisiae  "How fast is acetylation turnover in yeast?"
  Slide presentation for the 21th Annual West Coast Chromatin and Chromosomes Meeting, Asilimar Conference Center, Pacific Grove CA, December 16-19, 1999
  
  
• Alfalfa histone H3 variants : study of the dynamics of Synthesis and Turnover of histone H3.1 and H3.2 proteins and their Acetylation
  • Histone H3 variant genes: 56 H3.1 genes without introns versus 3 H3.2 genes WITH introns
  • Expression of cell cycle-dependent H3.1 genes versus cycle-independent H3.2 genes
  • Differences in mRNA stability of histone H3 variant transcripts
  • Turnover of histone H3 variants identifies H3.2 as a functional Replacement Histone,
    and reveals its assembly into remarkably unstable nucleosomes in transcribed plant chromatin
  
  
• Histone deacetylase inhibitor Trichostatin A (TSA) shows that histone H3 has likely a different role in chromatin fiber compaction than histones H4 and H2B:
  • Dynamics of histone acetylation in Chlamydomonas
  • Dynamics of histone acetylation in alfalfa
  
  
• Question: Does irreversible lysine methylation of histones have a function ?
  • Lysine20 in histone H4 of animals and fungi is methylated, limiting acetylation to 4 lysines;
    In plants and algae, all 5 N-terminal lysines of histone H4 can be acetylated
  • Lysine methylation of alfalfa histone H3 is extensive and limits reversible acetylation
  • Lysine methylation of Chlamydomonas H3 is significant and limits reversible acetylation
  Possible answer: control of reversible histone acetylation.
  Problem: control and site-specificity of histone methylation has not been studied.
  
  If you might want any of these slides as high-resolution PowerPoint files, send an email to <WaterborgJ@umkc.edu>

Assigned reading:

Click to READ Acrobat .PDF file with full-color illustrations
Hold Shift and Click to SAVE .PDF file   (Acrobat reader v3 plugin required)

1. Structure of the Nucleosome   1571 kb file! (includes all color figures at usable resolutions)
   Luger et al. (1997) Nature 389, 251
   For very high resolution .jpg picture files, you could look at these picture files:
   Fig. 1a,    Fig. 1b,    Fig. 1c,    Fig. 1d,    Fig. 2a-b,    Fig. 2c-d,    Fig. 2e-f,    Fig. 3a,    Fig. 3b,    Fig. 3c,    Fig. 4a-b,    Fig. 4c,    Fig. 4d,    Table 1.
2. The chromatin fiber as seen by atomic force microscopy   500 kb file!
   
   Leuba et al. (1998) Biophysical Journal 74, 2830
3. Chromatin Transcription and Histone Acetylation   153 kb file
   
   Wolffe and Pruss (1996) Cell 84, 817
4. Gene Repression and Histone Deacetylation   203 kb file
   
   Wolffe (1997) Nature 387, 16