Tat-peptide 168-189 is a cell-permeable and Tat-labeled fusion peptide, corresponding to residues 168-189 of rat G3BP1. Tat sequence from HIV, is placed at the least conserved end of the sequence, for cell permeability. Tat-peptide 168-189 is the negtive control of Tat-peptide 168-189 TFA (HY-P5118A), as Tat-peptide 168-189 TFA increases axon growth and increases the number of neurites per neuron.