The constitutively active form of human Rac1 protein contains a glutamine to leucine substitution at residue 61. The common name for this mutant is Rac1(Q61L) or L61Rac1. The leucine substitution prevents endogenous and GAP-stimulated GTPase activity of Rac1, hence the protein is always in the active, GTP-bound, state. A similar mutation in Ras (Ras(Q61L)) behaves as an oncogenic mutation.
Rac1(Q61L) has been expressed in a bacterial system. The protein is supplied as a lyophilized powder.When it is reconstituted in distilled water to 1 mg/ml, the protein is in the following buffer: 2 mM Tris pH 7.6, 0.5 mM MgCl
2 0.5% sucrose and 0.1% dextran. Protein concentration is determined by the Precision Red Advanced Protein Assay Reagent (Cat. #
ADV02).
The recombinant protein is 25 kDa, consisting of the 22 kDa Rac1 constitutively active protein plus a histidine tag in the amino-terminus.
For other forms of Rac1 as well as many other purified small G-proteins, see our main small G-protein product page.