[Histonet] X-gal staining

[Nicholas David Evans]

Hello,

I was wondering whether anyone might advise me on X-gal staining. 

I am looking at the expression of LacZ knocked into the locus of our gene
of interest. We cryoembed, take sections and stain for beta-galactosidase
activity using X-gal. The blue stain is often punctuate and noticeably
limited to the nucleus, whereas in other areas the staining is diffuse and
appears throughout the cytoplasm of the cells. I have guessed that this
may be related to the level of expression; i.e. that in cells with a low
reporter activity beta-gal is limited to the nucleus, but that at higher
expression the whole cell becomes riddled with it. If anyone knows
anything about the subcellular distribution/localisation of beta-gal in
mammalian cells, or can direct me to some good literature I would be
grateful.

Best wishes
Nick