Beta-Galactosidase, an important reporter gene marker encoded by lacZ, is commonly used for monitoring transfection efficiency in cultured cells and identifying expression of recombinant fusion genes. The ScienCellT beta-galactosidase Colorimetric Assay provides an easy-to-use method to detect beta-galactosidase by staining cells with 5-bromo-4-chloro-3-indolyl-beta-D-galactopyranoside (X-gal) at pH 7.4.
Kit Components
Cat. No
# of Vials
Reagents
Quantity
Storage
8068a
1
Staining solution A
1 ml
40C
8068b
1
Staining solution B
1 ml
40C
8068c
1
Staining solution C
0.2 ml
40C
8068d
1
Staining solution D
20 ml
40C
8068e
1
X-Gal solution
5 ml
-200C
8068f
1
100X Fixing solution
1 ml
40C
Quality Control
Human umbilical vessel endothelial cells (HUVECs) are transfected with Promega® ?SV-bata-galactosidase control vector. ß-Galactosidase Colorimetric Assay is applied to assay the gene expression 24 hours post transfection, as shown in Figure 1.
Procedures
Preparation of Reagents
Preparation of working fixing solution: Prepare working fixing solution by diluting 100× Fixing Solution stock 1:100 in PBS.
Preparation of working staining solution: Prepare fresh working staining solution based on the number of samples to be assessed. For each sample in 35 mm plate, prepare the following mixture:
100 µl of X-gal Solution
20 µl of Staining Solution A
20 µl of Staining Solution B
4 µl of Staining Solution C
+ 1856 µl of Staining Solution D
-------------------------------------------
2000 µl of working staining solution
Staining Protocol
Remove culture medium from cells and rinse cells twice with PBS.
Fix cells by incubating with 2 ml of working fixing solution for 3-5 minutes at room temperature.
Aspirate fixing solution and rinse the fixed cells three times with PBS.
Add 2 ml of working staining solution to the cells and incubate overnight at 37°C, the blue color should develop in ß-galactosidase expressing cells.*
Remove working staining solution and rinse cells twice with PBS, store cells in PBS at 4°C until examination under light microscope.
* Crystal deposition, which comes from unreacted X-gal, may be observed after incubation of cells with working staining solution. It can be minimized by pre-filtering the working staining solution with a 0.2 µm filter
Click the picture for large image
Fig 1. HUVECs transfected with Promega® ?SV-bata-galactosidase control vector.