Rac1 protein: His tagged: human constitutively active

Rac1 protein: His tagged: human constitutively active

Product Uses Include

  • Rac1 effector and GAP identification and binding studies
  • Activation of Rac1 effectors in vitro and in vivo
  • Stimulation of Rac1 phenotype by microinjection into cells

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 MgCl2, 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.

Protein purity is determined by scanning densitometry of Coomassie Blue stained protein on a 12% polyacrylamide gel. His-Rac1(Q61L) protein was determined to be 90% pure.


Figure 1: His-Rac1(Q61L) protein purity determination. A 10 µg sample of R6101 (His-Rac1(Q61L) molecular weight approx. 25 kDa) was separated by electrophoresis in a 12% SDS-PAGE system, and stained with Coomassie Blue.

Biological Activity
His-Rac1(Q61L) mutant protein binds GTP but its intrinsic GTPase activity has been eliminated, resulting in a constitutively active protein. The biological assay for His-Rac1(Q61L) activity consists of a pulldown assay using PAK-PBD beads (Cat. # PAK02). The PAK protein is an effector of Rac1 and will specifically bind to active GTP-Rac1. Stringent quality control ensures that > 80% of His-Rac1(Q61L) protein can be pulled down using this method.

For product Datasheets and MSDSs please click on the PDF links below.   For additional information, click on the FAQs tab above or contact our Technical Support department at tservice@cytoskeleton.com

AuthorTitleJournalYearArticle Link
Storey, Nina M. et al.Rac and Rho mediate opposing hormonal regulation of the ether-a-go-go-related potassium channelCurrent biology : CB2002ISSN 0960--9822

Coming soon!   If you have any questions concerning this product, please contact our Technical Service department at tservice@cytoskeleton.com