Hi. The fuson protein is zif268- linker(12 aa long consisting of G and S)- protein. when I overexpress it in BL21 or RIL, I get truncated bands. The protein should come at 80 kDa but i am getting intense bands at 37 and 26 kDa. I am inducing the overexpression using IPTG at 16 degree celsius overnight. I have tried shortening the the linker, but im still getting the truncated bands. Is there any suggestion for stable overexpression of zinc finger fusion proteins?