Measurement of The ADCK3 Transmembrane Helix Self-Association In Escherichia Coli Via the TOXCAT Assay

Abstract

The interaction of a-helices in the transmembrane region of certain proteins is important for the function of these proteins. The goal of our project is to study the self-association propensity of the transmembrane region of AarF Domain Containing Kinase 3 (ADCK3) and map its interaction interface. ADCK3 is a putative human mitochondrial kinase predicted to form a functional dimer. We measured the strength of the transmembrane helix-helix dimerization of ADCK3 via TOXCAT. Our results show that the transmembrane domain of ADCK3 forms a strong homo-oligomer due to the formation of the Ca-H hydrogen bonds between two amino acid residues. Site-directed mutagenesis is then carried out to map the interaction interface of ADCK3 to determine the amino acids that are important for self-association. From this experiment, we have also shown that the interaction interface of ADCK3 contains a Gly-zipper motif, a signature motif responsible for association in transmembrane regions of proteins.