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                                4. Transcription elongation control by RNA polymerase II- Dr. Ali Shilatifard
 
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                                5. The mechanisms and control of mRNA turnover in eukaryotic cells- Prof. Roy Parker
 
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                                6. Coupling transcription, RNA processing and RNA export- Prof. Grant Hartzog
 
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                                7. Dynamic chromatin: ATP-dependent chromatin remodeling machines- Prof. Bradley Cairns
 
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                                8. DNA methylation- Prof. Steve Jacobsen
 
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                                9. Visualization of transcription factor interactions in living cells- Prof. Tom Kerppola
 
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                                10. Accessing and using ENCODE data- Prof. Peggy Farnham
 
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                                11. The beta-globin locus- Dr. Ann Dean
 
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                                13. Transcriptional activation- Prof. Arnold Berk
 
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                                14. The regulation of Pre-Messenger RNA splicing- Prof. Douglas Black
 
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                                15. The E2F family and transcriptional control of the mammalian cell cycle- Prof. Brian Dynlacht
 
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                                16. Genome-wide analyses of protein-DNA interactions- Prof. Peggy Farnham
 
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                                18. Gene silencing by Polycomb complexes- Prof. Yi Zhang
 
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                                19. Eukaryotic gene regulation: from chromatin to transcription to mRNA processing- Prof. Michael Carey
- Prof. Stephen Smale
 
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                                20. Epigenetic information in gene expression and cancer- Prof. Siavash Kurdistani
 
Printable Handouts
Navigable Slide Index
- Gene silencing by polycomb complexes
- Hox genes
- PcG mutation results in homeotic phenotypes
- Drosophila PcG genes
- PcG proteins are conserved from fly to human
- PcG during the fly life cycle
- PcG maintains Hox genes silencing
- Questions concerning PcG silencing
- Covalent modifications in histones
- Histone methylation
- Multiple histone methyltransferases in HeLa cells
- Finding methyltransferases in HeLa cells
- HMTase complex
- Hox genes importance
- EED-EZH2 complex
- H3-K27 methylation
- Loss of E(Z) function
- Ubx gene silencing requirements
- ESC-E(Z) function in S2 cells
- E(Z) function in the wing discs
- Pc binds to H3 through its chromodomain
- Structural basis for binding of Pc to H3
- Proposed model of gene silencing
- PRC1 role in gene silencing?
- Study in yeast
- Establishment of an assay for E3 ligase activity
- Detection of nucleosomal-specific E3 activities
- H2A-K119 Ub-ligase
- H2A-Ub ligase activity purification
- Identity of the PRC1 complex components
- Finding the catalytic subunit
- H2A ubiquitination contribution?
- dRing colocalize with ubH2A
- Results of depletion of dRing by RNAi
- The E3 ligase defective Sce33M2 mutant
- Conclusions
- How H2A ubiquitylation causes gene silencing?
- Recruitment of E(Z) & PRC1 to PRE
- Pho & Phol association with PRE
- Role of Pho and Phol
- Results (1)
- Results (2)
- Results (3)
- Results (4)
- Model for PcG silencing process
- The diverse functions of the PcG complexes
Topics Covered
- Discovery of the Polycomb group (PcG) of proteins
- Role in embryogenesis
- Species conservation
- Latest developments in understanding molecular mechanism of gene silencing
- Evidence on hierarchical recruitment
Talk Citation
Zhang, Y. (2007, October 1). Gene silencing by Polycomb complexes [Video file]. In The Biomedical & Life Sciences Collection, Henry Stewart Talks. Retrieved October 31, 2025, from https://doi.org/10.69645/KARQ2300.Export Citation (RIS)
Publication History
Financial Disclosures
- Prof. Yi Zhang has not informed HSTalks of any commercial/financial relationship that it is appropriate to disclose.
 
       
    



















 
                    
                     
        
      
     
        
      
     
        
      
     
        
      
     
        
      
     
        
      
     
        
      
     
        
      
     
        
      
     
        
      
     
        
      
     
        
      
     
        
      
     
        
      
    