From mother to daughters: A central mystery in cell division solved

Dec 09, 2008

Researchers from the Ludwig Institute for Cancer Research at the University of California, San Diego School of Medicine have identified a key step required for cell division in a study that could help improve therapies to treat cancer. Their work describing the mechanism of the contractile ring – a structure that pinches the mother cell into two daughter cells – has been published in the December 5 issue of the journal Science.

The division of one cell into two is accomplished by the contractile ring, which is assembled from two protein filament types, actin and myosin, that are also used in muscle. During cell division, the genome is replicated and the two copies are separated to opposite sides of the cell by the mitotic spindle. The spindle then directs the assembly of a contractile ring, which forms a belt around the cell middle.

As happens during muscle contraction, the myosin filaments move along the actin filaments and constrict the ring. Constriction "tightens the belt," pinching the mother cell into two daughter cells.

"Normally, the contractile ring is built from long, straight actin filaments, which serve as tracks on which myosin filaments move along to drive constriction," said Karen Oegema, Ph.D, assistant professor at the Ludwig Institute and the Department of Cellular and Molecular Medicine at UC San Diego School of Medicine. "We discovered that a key step in ring constriction is turning off a pathway that would form branches on these long filaments, preventing them from being efficient tracks for myosin filament movement."

"This discovery will open the door to further studies of cell division that could improve chemotherapies for cancer," said first author Julie Canman, Ph.D., postdoctoral fellow in the areas of leukemia and lymphoma at UC San Diego and the Ludwig Institute. "Right now, drugs used in chemotherapy affect the division of all the body's cells, leading to adverse side effects, like sterility and death of the white blood cells that are essential for immunity," said Canman. "If we could specifically target the dividing cancer cells, we could improve on current chemotherapy to treat cancer with fewer side effects, allowing patients to continue therapy with a higher quality of life."

Source: University of California - San Diego

Explore further: Running robots of future may learn from world's best two-legged runners—birds

add to favorites email to friend print save as pdf

Related Stories

New high-resolution X-ray spectrometer for beam lines

Oct 28, 2014

NIST scientists have pioneered a technology that may speed the arrival of long-awaited materials and devices including advanced high-temperature superconductors and high-efficiency photovoltaic cells: A new ...

A glimpse at the rings that make cell division possible

Aug 22, 2014

Forming like a blown smoke ring does, a "contractile ring" similar to a tiny muscle pinches yeast cells in two. The division of cells makes life possible, but the actual mechanics of this fundamental process ...

'Zombie' bacteria are nothing to be afraid of

Aug 28, 2014

A cell is not a soap bubble that can simply pinch in two to reproduce. The ability to faithfully copy genetic material and distribute it equally to daughter cells is fundamental to all forms of life. Even ...

Recommended for you

Four new dragon millipedes found in China

35 minutes ago

A team of speleobiologists from the South China Agriculture University and the Russian Academy of Sciences have described four new species of the dragon millipedes from southern China, two of which seem to ...

Blocking a fork in the road to DNA replication

43 minutes ago

A team of Whitehead Institute scientists has discovered the surprising manner in which an enigmatic protein known as SUUR acts to control gene copy number during DNA replication. It's a finding that could shed new light on ...

Identifying the source of stem cells

44 minutes ago

When most animals begin life, cells immediately begin accepting assignments to become a head, tail or a vital organ. However, mammals, including humans, are special. The cells of mammalian embryos get to ...

User comments : 0

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.