Stem cells stand up for themselves

August 25, 2008

Adult stem cells are not pampered pushovers. O'Reilly et al. report that certain stem cells take charge of their surroundings, molding their environment to control their division and differentiation.

Some stem cells are cosseted like newborns. Neighboring cells cradle them in a structure called the niche. The niche not only nurtures its charges, it also dictates their behavior, determining whether they reproduce and specialize. The standard view is that the niche shapes stem cells, not vice versa.

O'Reilly et al. found evidence for more active stem cells while studying how the cells anchor themselves in the Drosophila ovary.

Previous work indicated that ovary stem cells attach to the niche through the protein E-cadherin. O'Reilly et al. tested whether the stem cells also depend on integrins, cell surface proteins that link molecules in the extracellular matrix to the cytoskeleton.

They found that follicle stem cells (FSC)—one type of ovary stem cell—drifted away from their niche when they carried mutant integrins.

These breakaway cells were abnormally shaped, divided more slowly than normal, and displayed some cancer-like characteristics, such as refusing to stop crawling even after contacting another cell.

Integrins hook onto an extracellular matrix protein called laminin A. FSCs pump out laminin A, and the scientists found that mutant cells that were unable to make the protein broke their moorings and reproduced sluggishly. Two other kinds of stem cells in the ovary—germline stem cells, which spawn the egg, and escort stem cells, which travel along with it—didn't rely on integrins for anchoring, the researchers showed. The team concluded that the interaction between laminin A and integrins ensures that FSCs remain in place, primed to divide. By laying down laminin A, therefore, FSCs help build their own niche.

Citation: O'Reilly, A.M., et al. 2008. J. Cell Biol. doi:10.1083/jcb.200710141.

Source: Rockefeller University

Explore further: Using modern genomics to turn alligator scales into birdlike feathers

Related Stories

Why we still don't understand sleep, and why it matters

October 23, 2017

One of my first jobs was to keep a lookout for lions. There are some occupations that are not suitable for someone with untreated narcolepsy and this is probably one of them. I was 22, a recent zoology graduate studying meerkats ...

Recommended for you

World's smallest tape recorder is built from microbes

November 23, 2017

Through a few clever molecular hacks, researchers at Columbia University Medical Center have converted a natural bacterial immune system into a microscopic data recorder, laying the groundwork for a new class of technologies ...

The world needs to rethink the value of water

November 23, 2017

Research led by Oxford University highlights the accelerating pressure on measuring, monitoring and managing water locally and globally. A new four-part framework is proposed to value water for sustainable development to ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.