Hi Kilian,

I routinely stain for GATA6 in mouse blastocysts.  In mouse blastocysts, the field seems to have adopted AF1700 from R&D systems.  Your staining looks OK in the top image but I'm not quite sure what I'm looking at -  I'm inexperienced with bovine embryos.  I like to test by Ab on embryos lacking the protein I'm staining for to make sure the signal goes away.  Maybe you could treat your embryo with MEK inhibitors or FGF and see if your signal changes in the way it's expected to based on treatment.  I also would recommend Jackson Lab's secondaries - they are very clean and might give you better signal to noise.

Good luck!

Tristan

Hi Tristan,

thanks for your answer!

I just cropped the original picture to the ICM only, thats why it doesn't quite look like a blastocyst. In bovine, second lineage differentiation begins at E8-E9, so we should see hypoblast precursor cellspositive for GATA6.

Thanks for your tip, I still have some FGF4 I will try out - that way I can also verify my NANOG staining ;)