TY - JOUR T1 - Structure and mechanism of human diacylglycerol acyltransferase 1 JF - bioRxiv DO - 10.1101/2020.01.06.896332 SP - 2020.01.06.896332 AU - Lie Wang AU - Hongwu Qian AU - Yin Nian AU - Yimo Han AU - Zhenning Ren AU - Hanzhi Zhang AU - Liya Hu AU - B. V. Venkataram Prasad AU - Nieng Yan AU - Ming Zhou Y1 - 2020/01/01 UR - http://biorxiv.org/content/early/2020/01/06/2020.01.06.896332.abstract N2 - Human diacylglycerol O-acyltransferase-1 (hDGAT1) synthesizes triacylglycerides and is required for dietary fat absorption and fat storage. The lack of 3-dimensional structure has limited our understanding of substrate recognition and mechanism of catalysis, and hampers rational targeting of hDGAT1 for therapeutic purposes. Here we present the structure of hDGAT1 in complex with a substrate oleoyl Coenzyme A at 3.1 Å resolution. hDGAT1 forms a homodimer and each protomer has nine transmembrane helices that carve out a hollow chamber in the lipid bilayer. The chamber encloses highly conserved catalytic residues and has separate entrances for the two substrates fatty acyl Coenzyme A and diacylglycerol. The N-terminus of hDGAT1 makes extensive interactions with the neighboring protomer, and is required for enzymatic activity. ER -