Patent ID: 7838249
Filing Date: 2010-11-23
Classification: C07K,C12Q

Abstract:
1. A method of determining intracellular Rab5 activity in a cell sample, comprising the steps of: providing a fusion protein, wherein the fusion protein comprises a Rab5-binding domain that specifically binds to an activated form of Rab5-GTP, and a tag conjugated thereto, wherein the tag is capable of binding to an affinity matrix for purification of Rab5-GTP; contacting the fusion protein with an affinity matrix or resin containing a molecule to which the tag of the fusion protein specifically binds; contacting a cell lysate with the fusion protein bound to the affinity matrix or resin such that Rab5-GTP present in the cell lysate will specifically bind to the fusion protein, thus forming a complex; rinsing the complex to remove the cell lysate; and determining the amount of Rab5-GTP present in the complex.