This week we looked at a paper describing the relationship between cellular focal adhesions, cell motility, and schizophrenia. http://www.sciencedirect.com/science/article/pii/S0006322313000917
Previous gene expression assays from olfactory mucosa neurons, which are excellent for disease modeling because of their multipotentcy, from patients with schizophrenia found differential expression in focal adhesion related genes, such as integrin genes (http://dmm.biologists.org/content/3/11-12/785.long). Differential expression was also found in the Focal Adhesion Kinase (FAK) pathway, which is central to the construction and maintenance of Focal Adhesions. Focal Adhesions are necessary for binding the cell to the extracellular matrix, which keeps it lodged in one place. Focal Adhesions are also important for cell motility insofar as cells need some sort of friction to move around. The fatty acid lipid membrane is very flexible and slippery due to its hydrophobicity; it needs the focal adhesions to provide an equal and opposite force for cellular motion. Imagine you’re on an ice rink, but your shoes can penetrate the ice and grip it so that you can walk.
However, these researchers found an increased level of cell motility in neurons of schizophrenic patients. Schizophrenic cells are faster and travel farther than control cells. Schizophrenic cells were also found to be less adherent, with less cells binding to plates when creating cell cultures. They found a reduced level of phosphylated FAK (pFAK) in patient cells but found that inhibiting FAK returned cell motility to control levels. They also found that inhibiting α3β1 integrins and α8β1 integrins also returned motility to normal. This implies that instead of the reduced level of FAK being the cause of the increased motility, the cause is instead a malfunction in the FAK pathway itself, of which α3β1 integrin and α8β1 integrin are a part of. They also found that patient focal adhesions were smaller, less common, and disassembled faster.
Unfortunately, there are an enormous amount of genes involved in cell motility and the FAK pathway. Any one of them could be affecting FAK, integrins, and cell motility at large. Hopefully our functional network programs will help elucidate some suspects.
This coming week, my primary goal will be identifying genes and pathways prominent in Schizophrenia pathology, while Miriam will be finding ones associated with cell motility