Discovery of Novel Filaments by UCSD Biologists Suggests a New Track for Cancer Treatment
September 16, 2010
By James Wilhelm
How do cells divide, muscles contract, and neurons make connections? The answer to each of these questions is the cytoskeleton - a set of proteins that can form filaments or tracks within the cell. The known filament forming proteins have roles in cancer and neurodegeneration, but it has been unclear whether these are the only tracks in the cell. Now a team of biologists at UC San Diego has discovered a novel set of intracellular tracks.
In the August issue of the Journal of Cell Biology, the researchers report the identification of 4 novel filaments - effectively doubling the number of known filaments. Surprisingly, all of the proteins that make up these filaments have been previously identified as components of the pathways that synthesize the building blocks of the cell. This suggested that filament formation represented a novel mechanism for turning different chemical pathways on or off. The UCSD researchers showed that this is the case for one of their proteins, CTPS, which had been previously implicated in chemotherapy resistance. Furthermore, the mutations in CTPS that confer chemotherapy resistance also prevent filament formation arguing that altering filament formation may provide a new "track" to treating cancer.
The road to discovery might not end there with these filaments, however. Like other cytoskeletal proteins, CTPS filaments are also found in the cellular extensions that neurons use to make contact with each other suggesting that the regulation of chemical pathways in the cell might not be the only function for these filaments. Given the role of other cytoskeletal proteins in neurodegenerative diseases, these new filaments are likely to provide new insights into neurological diseases as well. Clearly these new tracks are leading to some very interesting destinations.