Small G-proteins
PAK-PBD protein, GST-tagged

Cat. # PAK01

Product Uses Include

  • Precipitation of active Rac and Cdc42 from cell lysates
  • Inhibition of Rac and Cdc42 activity in vitro
  • Blocking of Rac and Cdc42 function in vivo by microinjection

Material
The Rac/Cdc42 (p21) binding domain (PBD) of the human p21 activated kinase 1 protein (PAK) protein has been expressed as a GST-fusion protein in E. coli. This protein binds binds specifically to GTP-bound, and not GDP-bound, Rac and Cdc42 proteins. The domain can therefore be used to specifically precipitate active, GTP-bound Rac and Cdc42 as well as to specifically block the activity of Rac and Cdc42 in vitro and in vivo.

The GST-PAK-PBD contains residues 67-150 of PAK. This region includes the highly conserved CRIB motif plus sequences required for the high affinity interaction with GTP-Rac and GTP-Cdc42.

The protein is supplied as 250 µg of lyophilized product and the protein is also available in a bead bound format (Cat. # PAK02). This product is also used in our Cdc42 and Rac activation assay Biochem Kits™ (Cat. # BK034 and BK035, repectively)

Purity
Protein purity is determined by scanning densitometry of Coomassie Blue stained protein on a 12% SDS polyacrylamide gel. GST-PAK-PBD protein is >80% pure (see Figure 1).


Figure 1: GST-PAK-PBD protein purity determination. A 10 µg sample of PAK01 was separated by electrophoresis in a 12% SDS-PAGE system and stained with Coomassie Blue.

Biological Activity
The PAK-PBD protein specifically recognizes and binds to the active, GTP-bound, form of Rac and Cdc42. Biological activity of PAK-PBD protein is therefore tested by its selectivity for GTPγS loaded Rac and Cdc42 proteins

Examples of publications where this product was used:
Scott, G., Leopardi, S., Printup, S. and Madden, B. C. (2002). Filopodia are conduits for melanosome transfer to keratinocytes. J. Cell Sci. 115, 1441-1451.

Product description Cat. # Amount Price & Order
PAK-PBD protein, GST-tagged PAK01-A 1 x 250 µg
PAK01-B 4 x 250 µg