>>->I am wondering if it is possibble to set up a quantitative
>>->immunoprecipitaion to analyse the regulation of expression of a
>>->particular cell surface receptor: What I would like to do is to
>>->immunoprecipitate the receptor and do a western afterwards with
>>->hormone treated and untreated cells and compare the relative
>>->expression. Do you think that this would be an appribiate approach??
>>I'd be very sceptical of such approach and certainly would not trust results
>>quantitatively. One poorly reproducible and highly non-linear technique
>>(IP) on top of another highly non-linear (western).
I wish to know why you are so skeptical about western.
I don't think western is HIGHLY non-linear so far as you determine the
linearlity
range of the amount relative to the density of a band in advance.
>The problem is that Western alone would not be sufficient sensitive to
>detect the receptor-therefore I do not think that IP is a redundant
>step-I would like to use it essenitally to increase sensitivity.
If your protein of interest cannnot be detected without IP (that is, using more
lysate than in western), IP followed by western for normalization seems
feasible.
I've been there with a kind of receptor tyrosine kinase.
There are a number of papers taking your approach for relative quantitation.
Kazuki
