Open Forum on Methodology
10 July 2003
While this thread was posted a while ago, I thought that some recent observations I have made might help. I was in the process of preparing nuclear extracts and kept the cytosolic fraction as well. I blotted both of these preparations (as well as a whole cell lysate) for p-Erk1/2 (Cell Signalling). The whole cell lysate prep had 2 bands - one at the expected size and another larger band. The cytosolic prep contained only the band of expected size, while the nuclear extracts had the larger band. I haven't characterized any of these, but I thought that the observation was interesting in view of the comments posted here. I hope that this might be of some help.
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