Cells: the most basic components that make up all living things. Despite their microscopic size, these structural units function in complex ways to take on fundamental biological processes. And sometimes, as we study them, we discover that they're even more bizarre than they look.
For starters, did you know that your cells have 'tentacles?' A recent study has discovered that cells have protrusions called filopodia, and they look just like the tentacles of a squid. Apparently, they have much more serious jobs than they look. "These structures play a pivotal role in... allowing cells to explore their environment, generate mechanical forces, perform chemical signaling, or convey signals via intercellular tunneling nano-bridges," says the recently published study. In a way, they do function as the "limbs" of the cell, helping it move about and interact with their environment.
Researchers involved in the study examined the ways in which these peculiar forms move about and communicate with other bodies surrounding them. "They're able to bend – twist, if you will – in a way that allows them to explore the entire space around the cell, and they can even penetrate tissues in their environment," said the lead author of the study, Niels Bohr Institute biophysicist Natascha Leijnse. The research also explained, "Here, we show that filopodia additionally explore their 3D extracellular space by combining growth and shrinking with axial twisting and buckling of their actin-rich core." The team compared this twisting and buckling motion to that of a rubber band.
In an experiment, the team was able to stop the movement of the filopodia using optical tweezers to hold tiny beads. The filopodium would then grow towards the 'tentacle' and get stuck on it, holding it in place. The success of the experiment has made scientists optimistic that it could also be applied to other cells, which also contain filopodia, such as cancer cells. "Cancer cells are noted for their being highly invasive. And, it is reasonable to believe that they are especially dependent on the efficacy of their filopodia, in terms of examining their surroundings and facilitating their spread," noted Poul Martin Bendix, a biophysicist at Niels Bohr Institute. "So, it's conceivable that by finding ways of inhibiting the filopodia of cancer cells, cancer growth can be stalled." Although a lot more research is needed before we can know for sure, this discovery definitely has us feeling optimistic. Stay tuned.