Amyotrophic lateral sclerosis (ALS) is a terrible disease that affects the way a person speaks, moves and even breaths, and is responsible for as many as 5 deaths for every 100,000 people over the age of 20. ALS is a progressive disease, affecting the neurons in the both the upper and lower brain way, as the nerve cells die, the disease spreads and infiltrates new cells. As to what causes the cells to die, it is believed to be led in part by a mismanagement of autophagy led by a trimeric protein complex composed of C9orf72, SMCR8 and WDR41. C9orf72 represents one of over 20 genes associated with familial ALS and accounts for as many as 40% of familial ALS . C9orf72 and SMCR8 are both DENN domain containing proteins and involved in autophagy regulation. Whereas WDR41 is a WD-repeat protein and is required for the recruitment of C9orf72 and SMCR8 to lysosomes.
Our goal is to structurally characterize the C9orf72-SMCR8-WDR41 trimeric complex using Cryo-EM in collaboration with Dr. Laura Diaz Saez from Kilian Huber lab at SGC Oxford. At the same time, we will aim to determine the crystal structure of WDR41 protein independently using X-ray crystallography at SGC Toronto to support drug-discovery efforts targeting WDR41 protein. For this reason, we first tested multiple combinations of the C9orf72-SMCR8-WDR41 trimeric complex Additionally, we have also designed several WDR41 constructs and placed them into a variety of vectors for both E.coli and SF9 insect cells expression systems in order to identify a well expressing and soluble WDR41 protein construct, suitable for crystallization studies.
Next week we will have preliminary results of construct designs, and test expression