What's the purpose of the extraction process? To screen for presence or to screen, quantify and purify?

Thanks a lot.

The purpose of the extraction is to see the protein expression.

For extracting the total leaf proteins grind on an ice bath, weighed amount of fresh leaves in say 10 mM phosphate buffer. You can make a 2 or 5 % extract. Centrifuge the crude extract to get most of the soluble proteins in the supernatant. You can fractionate according to the MW you are interested in.

Thank a lot. Could you suggest any recommended article or protocol as an attachment. Thanks

For quick qualitative extraction, I would just grind in 2x SDS buffer (fresh weight x 5 = volume). Boil + centrifuge and directly load onto gel.

I think the following article will be good to refer for your experiment.

Comparative evaluation of extraction methods for apoplastic proteins from maize leaves

Katja Witzel13, Muhammad Shahzad1, Andrea Matros2, Hans-Peter Mock2 and Karl H Mühling1* Plant Methods 2011, 7:48 doi:10.1186/1746-4811-7-48

Thanks all