Trouble detcting phosphJNK by western - (Mar/29/2002 )

Hi
I'm trying to detect the phosphorylated form of JNK by western blotting. Sometimes I get a signal sometimes I don't. I'm using a triton based lysis buffer that contains NaF, leupeptin, aprotinin, pepstatin, PMSF, NaV04, and B-glycerophophate.
Has anyone any ideas? Or experienced similar problems?

perhaps you have excess phosphatase activity? Not too sure tho.
I believe people use b-glycerophosphate as a substrate for Phosphatases.  This may act as a inhibitor in ur case, but i really don't know how potent it is...

Perhaps you ar not consistent with your experiments in terms of activating JNK's?  

sorry can't help you too much.

sean