Actin effector: Small G

Migration is initiated by protrusion of the leading edge and formation of new actin filaments. Small G proteins play important roles, for example to induce lamellipodia, or to stimulate filopodia or tail retraction. Activation of Rac, Cdc42 or Rho is very important and requires fast and easy-to-use tools for analysis.

Small G-protein activation assays:  G-LISA® technology

Simple and quick protocol

The G-LISA® Assay is based on using a 96-well plate where a specific Small G -GTP-binding domain has been covently coupled to the wells. Active GTP-bound specific Small G protein in lysate will bind to the wells while inactive GDP-bound protein is washed away.

The bound active Small G protein is subsequently detected with a specific antibody and chemiluminescent or optical density measurement.

As the affinity wells are supplied in strips which can be divided, each kit can be used for anywhere from 2 to 96 assays.


G-LISA® versus traditional pull-down

The traditional way of measuring the level of activation of a Small G protein has been to do so-called pulldown activation assays. 

However, these methods are time consuming, require large amount of sample, tend to not be very consistent and are not suitable for high throughput screens. To circumvent these issues, the G-LISA® assay was developped by Cytoskeleton, Inc. (patent pending).

The G-LISA® are ELISA based-Small G-protein activation assays with which you can measure the GTP form of small G-proteins from cells lysates or tissues and all in less than 3 hours.

These assays are simple, fast and require only small amounts of sample (5-25 µg cell protein). They yield quantitative and accurate data and are suitable for high throughput screens.

There are G-LISA® kits for...

  Colorimetric Detection Luminescent Detection
RhoA G-LISA® Activation Assay BK124 BK121
Rac1,2,3 G-LISA® Activation Assay BK125  
Rac1 G-LISA® Activation Assay BK128 BK126
Cdc42 G-LISA® Activation Assay BK127  
RalA G-LISA® Activation Assay BK129  
Ras G-LISA® Activation Assay BK131