Navigation Links
Checkered history of mother and daughter cells explains cell cycle differences
Date:10/19/2009

When mother and daughter cells are created each time a cell divides, they are not exactly alike. They have the same set of genes, but differ in the way they regulate them. New research now reveals that these regulatory differences between mother and daughter cells are directly linked to how they prepare for their next split. The work, a collaboration between scientists at Rockefeller University and the State University of New York, Stony Brook, may ultimately lead to a better understanding of how cell division goes awry in different types of cancer. The findings are reported in this week's PLoS Biology.

"You can basically think of mother and daughter cells as different cells just like you would a neuron and liver cell but on a much subtler level," says first author Stefano Di Talia, who received his Ph.D. from Rockefeller in 2009. "We found that their differences in gene expression are also what makes the mother and daughter cells start their cell cycles differently."

When a mature cell divides, it produces a mother and a daughter cell, the daughter being smaller than the mother, explains Di Talia, who is now a postdoc at Princeton University. Since the 1970s, it was thought that both mother and daughter cells use the same gears and levers to prepare for cell division. The only difference was that the daughter cell would take longer to start dividing on account of its size.

This tidy explanation now gives way to a more nuanced version, the seeds of which can be traced to research from the University of Wisconsin in 2003. It was then proposed that the size of the daughter cell has no bearing on whether it is ready to divide. What matters is that the daughter cell, and not the mother cell, receives a protein called Ace2 at the time the two cells are born. "This model was against the accepted dogma and against our own previous findings. Our work was an attempt to resolve the debate," says Di Talia.

Di Talia and Frederick R. Cross, head of Rockefeller's Laboratory of Yeast Molecular Genetics and a researcher who, like the Wisconsin group, works with budding yeast, seem to have reconciled the two theories and in the process nailed down new details.

The researchers found that both mothers and daughters do control and sense their size before committing to divide but the levers and gears that they use to make that commitment are different. The reason: Daughters, but not mothers, receive the protein Ace2 as well as a never-before-implicated protein called Ash1, which, like Ace2, controls the levers that crank genes into gear.

In their work, Di Talia and Cross studied a phase of the cell cycle known as G1, during which cells determine whether they are healthy enough to enter another grueling phase of division. G1 is considered critical because mistakes in this process can lead to cancer.

Di Talia and Cross, with colleagues Bruce Futcher and Hongyin Wang at SUNY Stony Brook, found that daughter cells, which normally have Ace2 and Ash1, interpret their size as 20 percent smaller than their birth twin. The researchers show that, without these proteins, daughter cells begin dividing as if they were mother cells, even at a size that would normally be deemed too small. When Ace2 and Ash1 were genetically manipulated to localize into mothers as well, the opposite happened: they unnecessarily continued to grow and began dividing as if they were daughters.

This critical finding showed that the direct target of these two proteins is a gene called CLN3, which scientists have long suspected is the ultimate green light for cells to start dividing. The reason daughter cells spend a longer time preparing for cell division is because both Ace2 and Ash1 lower the expression of CLN3. To make sure daughter cells do not start dividing before they are ready, and as backup, Ace2 also turns on production of Ash1.

"This work builds on our previous findings very nicely," says Di Talia. "That CLN3 is the central regulator of this cell cycle phase and that it is controlled very precisely shows that even small changes can result in big differences."


'/>"/>

Contact: Thania Benios
tbenios@rockefeller.edu
212-327-7146
Rockefeller University
Source:Eurekalert

Related biology news :

1. Algae and pollen grains provide evidence of remarkably warm period in Antarcticas history
2. End of an era: New ruling decides the boundaries of Earths history
3. Scientists use microRNAs to track evolutionary history for first time
4. Salt marshes: A natural and unnatural history
5. Geography and history shape genetic differences in humans
6. History of hyperactivity off-base, says researcher
7. Penn Medicine honored for its historic role in the history of microbiology
8. Tiny differences in our genes help shed light on the big picture of human history
9. DOE makes largest Danforth Campus research award in history
10. Study of protein structures reveals key events in evolutionary history
11. Chantix side effects no worse with depression history
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/22/2016)... American College of Medical Genetics and Genomics was once again ... of the fastest-growing trade shows during the Fastest 50 Awards ... Las Vegas . Winners are ... of the following categories: net square feet of paid exhibit ... 2015 ACMG Annual Meeting was ranked 23 out of 50 ...
(Date:6/20/2016)... -- Securus Technologies, a leading provider of civil ... investigation, corrections and monitoring announced that after exhaustive ... the final acceptance by all three (3) Department ... (MAS) installed. Furthermore, Securus will have contracts for ... October, 2016. MAS distinguishes between legitimate wireless device ...
(Date:6/9/2016)... Paris Police Prefecture ... solution to ensure the safety of people and operations in ... major tournament Teleste, an international technology group specialised ... today that its video security solution will be utilised by ... public safety across the country. The system roll-out is scheduled ...
Breaking Biology News(10 mins):
(Date:6/27/2016)... , June 27, 2016   Ginkgo Bioworks , ... industrial engineering, was today awarded as one of ... of the world,s most innovative companies. Ginkgo Bioworks ... for the real world in the nutrition, health ... work directly with customers including Fortune 500 companies ...
(Date:6/24/2016)... , ... June 24, 2016 , ... While the majority ... as the Cary 5000 and the 6000i models are higher end machines that use ... height of the spectrophotometer’s light beam from the bottom of the cuvette holder. ...
(Date:6/23/2016)... ... June 23, 2016 , ... UAS LifeSciences, one of the ... brand, UP4™ Probiotics, into Target stores nationwide. The company, which has been manufacturing ... to its list of well-respected retailers. This list includes such fine stores as ...
(Date:6/23/2016)... , June 23, 2016 A person commits ... the crime scene to track the criminal down. ... U.S. Food and Drug Administration (FDA) uses DNA evidence to ... Sound far-fetched? It,s not. The FDA has ... to support investigations of foodborne illnesses. Put as simply as ...
Breaking Biology Technology: