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 September 17, 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 September 17, 2014).

Share This



More Plants & Animals News

Wednesday, September 17, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Some Tobacco Farmers Thrive Amid Challenges

Some Tobacco Farmers Thrive Amid Challenges

AP (Sep. 16, 2014) The South's tobacco country is surviving, and even thriving in some cases, as demand overseas keeps growers in the fields of one of America's oldest cash crops. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Scientists Given Rare Glimpse of 350-Kilo Colossal Squid

Scientists Given Rare Glimpse of 350-Kilo Colossal Squid

AFP (Sep. 16, 2014) Scientists say a female colossal squid weighing an estimated 350 kilograms (770 lbs) and thought to be only the second intact specimen ever found was carrying eggs when discovered in the Antarctic. Duration: 00:47 Video provided by AFP
Powered by NewsLook.com
Raw: Scientists Examine Colossal Squid

Raw: Scientists Examine Colossal Squid

AP (Sep. 16, 2014) Squid experts in New Zealand thawed and examined an unusual catch on Tuesday: a colossal squid. It was captured in Antarctica's remote Ross Sea in December last year and has been frozen for eight months. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Ivorians Abandon Monkey Pets in Fear Over Ebola Virus

Ivorians Abandon Monkey Pets in Fear Over Ebola Virus

AFP (Sep. 16, 2014) Since the arrival of Ebola in Ivory Coast, Ivorians have been abandoning their pets, particularly monkeys, in the fear that they may transmit the virus. Duration: 00:47 Video provided by AFP
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