TAT-DEF-Elk-1 TFA is a cell-penetrating peptide Elk-1 inhibitor, mimics and specifically interferes with the DEF domain of Elk-1. TAT-DEF-Elk-1 blocks Elk-1 phosphorylation and prevents Elk-1 nuclear translocation without interfering with ERK nor MSK1 activation. TAT-DEF-Elk-1 is a useful tool to analyze the role of Elk-1 in this process during the development of neuronal plasticity

ELK1:

Elk-1 phosphorylation on Ser383/389 has a dual function and triggers both Elk-1 nuclear translocation and SRE-dependent gene expression. TAT-DEF-Elk-1 (5 μM; 2 hours) treatment shows significant inhibition of c-Fos, Zif268, and JunB, but has no effects on c-Jun expression. TAT-DEF-Elk-1 (5-10 μM; 1 hour) specifically inhibits glutamate-induced elk-1 activation and does not interfere with ERK, MSK-1, or CREB phosphorylation [1].

TAT-DEF-Elk-1 (i.p.; 1mg/kg; daily; 14 days) reflects antidepressant efficacy in mice, it decreases immobility similar to the antidepressant desipramine and fluoxetine [2].