An experiment was performed to induce and purify the protein…

An experiment was performed to induce and purify the protein X. In the gel below, Lane 1 shows non-induced cells; Lane 2 shows induced cells; Lane 3 is purified MBP-X; Lane 4 is the protein after TEV cleavage; Lane 5 is the flowthrough after the cleaved sample has been run through an amylose column; Lane 6 is the purified TEV protease. Which band represents the protein of interest?