Poster Presentation The 42nd Lorne Conference on Protein Structure and Function 2017

Structural and functional characterisation of human intracellular copper trafficking pathways (#206)

Shadi Maghoolpilehrood 1 , Ann Kwan 2 , Joel Mackay 2 , Sharon La Fontaine 3 , Zhiguang Xiao 4 , Blaine Roberts 5 , Megan Maher 1
  1. La Trobe University, Bundoora, VIC, Australia
  2. School of Molecular Bioscience, University of Sydney, Sydney, NSW , Australia
  3. School of Life and Environmental Sciences, Deakin University, Melbourne, Victoria, Australia
  4. School of Chemistry and The Bio21 Molecular Science and Biotechnology Institute, Melbourne University, Melbourne, Victoria, Australia
  5. University of Melbourne, The Florey Institute of Neuroscience and Mental Health, Melbourne, VIC , Australia

Copper, a redox active metal, is a vital trace element required by all living organisms. In humans, copper dysregulation leads to disorders such as Menkes and Wilson diseases, Alzheimer’s disease, and familial amyotrophic lateral sclerosis (FALS). In human cells, copper concentrations are regulated via control of the levels of the copper transporter 1 (Ctr1) at the plasma membrane. In addition, a metallochaperone (Atox1) traffics copper to the ATP7A and ATP7B proteins, which on copper loading are translocated from the trans-Golgi network to vesicles and/or the plasma membrane for copper export.

 

In this study, we have investigated the regulatory role of the enzyme human glutathione reductase (hGrx1), a cytosolic thiol disulfide oxidoreductase, in cellular copper trafficking pathways. By using LC-ICP-MS we were able to study the copper exchange between the proteins hGrx1, Atox1, and the metal-binding domains 4 (MBD4) and 5-6 (MBD5-6) from the ATP7B transporter in addition to defining the affinities of protein- protein interactions by NMR studies. The results of these investigations will be described.