Cytoskeleton's GEFs, Small GTPases & Activation Assay Promo
15% discount on listed items
Validity: 15th Mar 2022 to 30th Apr 2022
Small G-proteins > Proteins, Modular Proteins
Cytoskeleton is the pre-eminent supplier of Rho and Ras family small G-proteins (SGPs). The proteins are available in wild-type, constitutively active and dominant negative forms. It is also pre-eminent supplier of GAP and GEP proteins. All these products have been fully QC'd for high activity and purity.
The Ras superfamily of small GTPases consist of more than 150 members, which based on their sequence homology, are divided into several subfamilies such as Rho, Ras, Ran, Rab, Arf and Rad/Rem/Gem/Kir. This group of small GTPases serve as binary switches cycling between GDP-bound inactive and GTP-bound active state, and have been shown to regulate biological processes including cell growth, cell differentiation, and cell movement. Small G-protein nucleotide exchange is modulated by several classes of proteins including guanine nucleotide exchange factors (GEFs), GTPase activating proteins (GAPs) and guanine nucleotide dissociation inhibitors (GDIs). Cytoskeleton, Inc. has a wide assortment of Small G-protein tools and reagents to aide in your small G-protein investigation.
Signal Transduction Assay
At Cytoskeleton, they develop signal transduction kits which are focused on small G-protein research. In particular Cytoskeleton provide kits for measuring the activated forms of Rho and Ras family members, and their intrinsic properties of GTPase and GTP/GDP exchange.
Activation assays come in two types, the G-LISA 96-well format and the traditional pull-down variety. The G-LISA format is very accurate and flexible in that the 96-wells are divisible into 8-well strips making it the most economical option for a project. The pull-down variety has been traditionally used for testing small numbers of samples or a quick look-see experiment where low accuracy is acceptable. Unfortunately due to the low accuracy of the pull-down technique and low endogenous activation levels in some samples (may be only 10 to 20% increase in activity levels) some positive results may not be found. We recommend utilizing the GLISA assay wherever possible due to the greater confidence obtained from higher accuracy.
Small G-proteins > Small GTPase Affinity Beads
As with the G-LISA and Pull-Down Activation Assays, the PAK-PBD, GGA3-PBD, Rhotekin-RBD, and Raf-RBD bead conjugates are useful tools to separate the active form of small G-proteins from cell lysates. PAK beads are ideally suited for Cdc42 and Rac1 studies whereas GGA3 is specific for Arf1 and Arf6, while Rhotekin is specific for Rho and Raf-beads are specific for Ras sub-family members. The protocols (including lysis buffer formulation) for using the beads are described in the datasheets below. The beads are also flexible with respect to using them for multiple isoforms of Rac or Rho; just use a specific antibody for the isoform of interest (e.g., a RhoC antibody to look at active RhoC instead of RhoA or B). The beads are also colored (a Cytoskeleton innovation in 2004) to easily identify pellet material.
Activations Assays > Pull Down Assays
Small G-protein pull-down activation assays utilize affinity beads linked to an effector protein that selectively binds the active GTPase, followed by Western blot quantitation with highly isotype specific antibodies. These assays are compatible with mouse, rat, and human tissue and cell lysates. All reagents to perform a non-stop experiment are included. In addition, small G-protein affinity beads, antibodies, proteins, activators, and inhibitors are available for individual purchase.
Small G-proteins > Antibodies
Cytoskeleton provides a range of antibodies raised to the Rho family of small G-proteins. They have exceptional isoform specificity and each are provided with human platelet extract as a positive control.