Telomerase, a ribonucleoprotein, is responsible for maintaining the telomere 
length and therefore promoting genomic integrity, proliferation, and lifespan. 
In addition, telomerase protects the mitochondria from oxidative stress and 
confers resistance to apoptosis, suggesting its possible importance for the 
surviving of non-mitotic, highly active cells such as neurons. We previously 
demonstrated the ability of novel telomerase activators to increase telomerase 
activity and expression in the various mouse brain regions and to protect motor 
neurons cells from oxidative stress. These results strengthen the notion that 
telomerase is involved in the protection of neurons from various lesions. To 
underline the role of telomerase in the brain, we here compare the activity of 
telomerase in male and female mouse brain and its dependence on age. TRAP assay 
is a standard method for detecting telomerase activity in various tissues or 
cell lines. Here we demonstrate the analysis of telomerase activity in three 
regions of the mouse brain by non-denaturing protein extraction using CHAPS 
lysis buffer followed by modification of the standard TRAP assay. In this 2-step 
assay, endogenous telomerase elongates a specific telomerase substrate (TS 
primer) by adding TTAGGG 6 bp repeats (telomerase reaction). The telomerase 
reaction products are amplified by PCR reaction creating a DNA ladder of 6 bp 
increments. The analysis of the DNA ladder is made by 4.5% high resolution 
agarose gel electrophoresis followed by staining with highly sensitive nucleic 
acid stain. Compared to the traditional TRAP assay that utilize (32)P labeled 
radioactive dCTP's for DNA detection and polyacrylamide gel electrophoresis for 
resolving the DNA ladder, this protocol offers a non-toxic time saving TRAP 
assay for evaluating telomerase activity in the mouse brain, demonstrating the 
ability to detect differences in telomerase activity in the various female and 
male mouse brain region.