Commercial pre-made Notherns

[john brennand]

Yeah - I noticed the same phenomenum with the Clontech northern blots 
when using the gapdh "control" probe.

I had an ultimately unsatisfactory dialog with them but the bottom line 
seems to be:-

gapdh mRNA levels do vary between tissues quite significantly, eg muscle 
is very high - so this probe is no indicator of RNA loading.  They said 
that they were sure that loadings were pretty equal on the blots - as 
judged by staining and actin probing.  Ive posted on this before saying 
I dont think that that is a good control either but -

I think that the blots are probably ok because if you probe them with a 
"true" housekeeping gene control probe, such as HPRT, the signals are 
fairly even

John