Biologists at Florida State University (FSU) have conducted an investigated in order to watch the way cells crawl. In every human body, millions of cells crawl all over the body doing mainly good things. The study is published online in the journal Current Biology and funded by the National Institutes of Health.
FSU cell biologist Tom Roberts has investigated the mechanical and molecular ways cells move absent bones, muscles or brains for 35 years, he explained:
“This is not some horrible sci-fi move come true but, instead, normal cells carrying out their daily duties.”
Cells use millions of tiny fibers to push themselves forward, they then retract their rears in a smooth, coordinated extension contraction manner. However, there has always been one problem with investigating how they crawl. While in the body they move around similar to an inch worm, but when they are placed under a microscope the crawling changes or stops.
However, Roberts and his former FSU post-doctoral associate Katsuya Shimabukuro have discovered a new way around uncooperative human cells. Shimabukuro carefully disassembled and reconstituted a worm sperm cell in order to replicate the way cells move under the microscope. However, in order to get the worm sperm cells to move like they naturally would, the researchers created conditions to promote the cell’s natural pull-push crawling motions, giving the investigators the chance to watch it move.
Roberts called Shimabukuro’s work “careful, clever work.” This work revealed images of cell motility that should help to pinpoint just how cells crawl.
Roberts explained:
“Understanding how cells crawl is a big deal. The first line of defense against invading microorganisms, the remodeling of bones, healing wounds in the skin and reconnecting of neuronal circuits during regeneration of the nervous system – all depend on the capacity of specialized cells to crawl.
On the downside, the ability of tumor cells to crawl around is a contributing factor in the metastasis of malignancies. But we believe our achievements in this latest round of basic research could eventually aid in the development of therapies that target cell motility in order to interfere with or block the metastasis of cancer.”
Roberts said that they used worm sperm cells because they are different from the majority of cells in that they don’t use molecular motor proteins to help their contractions, they simply shimmy along simply by putting together and tearing down their filaments. They also make a good model because they are similar to a human cell but they have fewer moving parts, which makes it easier to take them apart and reassemble them compared to brain or cancer cells.
With this new ability to reassemble amoeboid motility in vitro, cell biologists such as Roberts might learn the answers to some important questions. Among them: How can some cells continue to crawl even after investigators have disabled their supply of myosin, the force-producing “mover protein” that functions like a motor to help power muscle and cell contraction?
The next move for Roberts and his team will be to find out if their findings apply to more conventional crawling cells, including tumor cells. Roberts stated: “As always, there will be more questions. Are there multiple mechanisms collaborating to drive cell body retraction? Is there redundancy built into the motility systems?”
Written by Grace Rattue