KOHNE: Could there be membrane material 

 in this chromatin preparation? There have been 

 reports that even purified DNA has some mem- 

 brane in it. 



CHALKLEY: We've never treated with de- 

 oxycholine. This might be worth doing, though I 

 suspect it would dissociate some histone from 

 the DNA. 



PAPACONSTANTINOUS: You know, there's 

 one question that hasn't come up yet, and I don't 

 know that there's any answer. That is, how does 



your system fit in with the question "Is the 

 genome read when the cell is replicating or is 

 it not read?" K the genome isn't read during 

 replication, then you've got to fit up all your 

 repressors for replication and then pull them 

 back off again. 



CHALKLEY: I don't think I have an answer 

 to that. 



PAPACONSTANTINOU: Well, I don't know 

 whether there is an answer to that very ques- 

 tion of whether it's being read or not. 



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