Featured Research

from universities, journals, and other organizations

Scientists Deconstruct Cell Division

Date:
February 11, 2009
Source:
Carnegie Institution
Summary:
The last step of the cell cycle is the spectacularly dynamic and complicated mitosis phase, which leads to the duplication of one mother cell into two daughter cells. In mitosis, fibrous structures called spindles form. Scientists have tried for years to unravel the process of spindle assembly. Now, researchers have found that two proteins used in other functions -- dynein and Nudel -- are essential to regulate assembly of the spindle matrix.

This image shows an in vitro assay for the assembly of lamin B containing spindle matrix along microtubules during spindle assembly. Yellow arrows point to the lamin B network assembled along the microtubules.
Credit: Image courtesy Yixian Zheng

The last step of the cell cycle is the brief but spectacularly dynamic and complicated mitosis phase, which leads to the duplication of one mother cell into two daughter cells. In mitosis, the chromosomes condense and the nucleus breaks down. Fibrous structures called spindles form, which then move the chromosomal material toward opposite ends of a cell and help partition other cell contents. If something goes wrong, diseases such as cancer can arise.

Scientists have tried for years to unravel the process of spindle assembly. Now, researchers at Carnegie's Department of Embryology have found that two proteins— dynein and Nudel—involved in other cell-division functions, are essential to regulate assembly of the spindle matrix.

"The mechanisms that cells use during division to partition both chromosomes and regulatory factors into their daughters are widely recognized as among the most fundamental processes in all of biology. During the last several years no one has done more than Yixian Zheng to broaden our understanding of how dividing cells control these critical events," said Allan Spradling, Department of Embryology director.

"To ensure proper cell division, the mother cell needs to separate its genetic materials, the chromosomes, equally, but also partition its cellular content properly into daughter cells," explained co-author Yixan Zheng. "Cell division allows a fertilized egg to develop into multicellular organisms with different types of cells. It also replenishes adult tissues, such as skin and bones. Forming a spindle requires the assembly of a 'skeleton' from tube-like microtubules and the construction of a poorly defined scaffold called a spindle matrix."

In 2006, Zheng and colleagues discovered that a protein found in the nucleus during the interphase of the cell division cycle, called lamin-B, is a structural component of the spindle matrix (Science 31 March 2006, 311: 1887-1893). Based on this finding, she and colleagues have now isolated the spindle matrix. Interestingly, both dynein and Nudel are components of the spindle matrix. Nudel binds to lamin-B and brings it to microtubules where both Nudel and dynein then help the lamin-B assemble into the spindle matrix. The lamin-B-containing spindle matrix, in turn, works with microtubules to orchestrate spindle assembly and cell division.

"Isolating the spindle matrix and identifying its components has also allowed us to show that the matrix contains not only factors important for spindle assembly, but also proteins essential for cell fate choices," remarked Zheng. "We believe that by understanding how the spindle matrix is assembled in mitosis, it will be possible to understand how, after mitosis, two daughters can chose to become the same or different cell types—a decision that cells need to make both during the development of an organism and during the maintenance of adult tissues."

The research is published on line in the February 8 Nature Cell Biology.


Story Source:

The above story is based on materials provided by Carnegie Institution. Note: Materials may be edited for content and length.


Cite This Page:

Carnegie Institution. "Scientists Deconstruct Cell Division." ScienceDaily. ScienceDaily, 11 February 2009. <www.sciencedaily.com/releases/2009/02/090208133145.htm>.
Carnegie Institution. (2009, February 11). Scientists Deconstruct Cell Division. ScienceDaily. Retrieved July 23, 2014 from www.sciencedaily.com/releases/2009/02/090208133145.htm
Carnegie Institution. "Scientists Deconstruct Cell Division." ScienceDaily. www.sciencedaily.com/releases/2009/02/090208133145.htm (accessed July 23, 2014).

Share This




More Plants & Animals News

Wednesday, July 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Michigan Plant's Goal: Flower and Die

Michigan Plant's Goal: Flower and Die

AP (July 22, 2014) An 80-year-old agave plant, which is blooming for the first and only time at a University of Michigan conservatory, will die when it's done (July 22) Video provided by AP
Powered by NewsLook.com
San Diego Zoo Welcomes New, Rare Rhino Calf

San Diego Zoo Welcomes New, Rare Rhino Calf

Reuters - US Online Video (July 21, 2014) An endangered black rhino baby is the newest resident at the San Diego Zoo. Sasha Salama reports. Video provided by Reuters
Powered by NewsLook.com
Shark Sightings a Big Catch for Cape Tourism

Shark Sightings a Big Catch for Cape Tourism

AP (July 21, 2014) A rise in shark sightings along the shores of Chatham, Massachusetts is driving a surge of eager vacationers to the beach town looking to catch a glimpse of a great white. (July 21) Video provided by AP
Powered by NewsLook.com
$23.6 Billion Awarded To Widow In Smoking Lawsuit

$23.6 Billion Awarded To Widow In Smoking Lawsuit

Newsy (July 20, 2014) Cynthia Robinson claims R.J. Reynolds Tobacco Company hid the health and addiction risks of its products, leading to the death of her husband in 1996. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins