electrophoresis of nuclear extracts

[MC_CARTHY,DAVE]

 We are trying to fractionate proteins in human nuclear extracts in SDS
 polyacrylamide gels.  Althugh we observe sharp protein bands in 13%
 polyacrylamide, we have problems with gels that are below 10%
 polyacrylamide.  The protein forms vertical streaks along the edges of
 the lanes.  Equivalent amounts of protein from E. coli extracts do not
 show this sensitivity to polyacrylamide percentage in the same gels.

 Have others had this problem with nuclear extracts?  Are there any ways
 to avoid this?  

 Thanks
 Dave  

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  Dave McCarthy                 | PHONE: (405) 325-1658      
  University of Oklahoma        | FAX: (405) 325-7619
  770 Van Vleet Oval            | e-MAIL:mccarthy at aardvark.ucs.uoknor.edu
  Norman, OK 73019-0245 USA     | 
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