The Vande Velde Lab
We are focused on understanding the way by which neurons are lost in the fatal neurodegenerative disease, amyotrophic lateral sclerosis (ALS). ALS is also known as Lou Gehrig's Disease and Motor Neuron Disease.
We use a wide range of experimental approaches from cell biology, biochemistry, and neuroscience to determine the signalling mechanisms affected in ALS. We use mammalian tissue culture models, including primary neurons, validated rodent models of disease, and human patient samples to determine the biology that underlies ALS. It is our intent to apply our findings to the development of therapeutics and biomarkers.
We have two primary interests:
- TDP-43 and RNA granule dynamics (stress granules)
- Misfolded SOD1 and mitochondrial and cellular function
TDP-43 AND RNA GRANULES
Li et al., JCB, 2013
One first-line protective mechanism by which a cell responds to an adverse environmental insult or stressor is the formation of stress granules (SGs). The primary impetus of the process favours cellular recovery, thus a failure of this system can have drastic consequences. There is increasing evidence that a failure of the SG response is critical to the pathobiology of ALS. Several ALS-causing genes participate in the SG pathway, thus SGs sit at a critical convergence point in modern ALS research. We have discovered that TDP-43 regulates SG assembly in such a way as to disrupt SG interactions with other RNA granules. A deeper understanding of this mechanism will provide essential knowledge for the design of new strategies for the management and treatment of both sporadic and familial ALS. This work will also identify new proteins and/or susceptibility factors involved in this disease for future study as potential biomarkers/therapeutic targets.
New work also includes exploration of the role of TDP-43 in the alternative splicing of hnRNP A1, another ALS-related RNA binding protein.
A portion of familial ALS results from mutations in superoxide dismutase 1 (SOD1) causing protein misfolding. The ALS research community largely agrees that misfolded SOD1 lies at the root of toxicity in familial ALS (and some might argue sporadic ALS also). We have demonstrated that several SOD1 mutants adopt a misfolded conformation that preferentially and progressively associates with the surface of spinal cord mitochondria prior to disease onset. Mitochondria have long been implicated in ALS pathogenesis and we have established a link between the deposition of misfolded SOD1 and mitochondrial damage and/or failure of mitochondrial quality control mechanisms. We are further investigating the consequences of this association and exploring the concept that distinct forms of misfolded SOD1 exist.