Featured Research

from universities, journals, and other organizations

Key role for a protein in cell division described

Date:
December 31, 2010
Source:
Rockefeller University
Summary:
Just before a cell divides into two -- the basic act of reproducing life -- the cellular environment must be exquisitely prepared. The exact timing and localization of the vast array of molecules and processes involved in duplicating chromosomes and separating the offspring from the parent is one of the basic wonders of biology and is at the core of both healthy living and diseases such as cancer, which arise when the process goes awry. Now scientists have detailed the role of one protein, PRC1, that acts in the penultimate stage of cell division, helping to form the architectural structures, called central spindles, needed before the cell splits in two.

Just before a cell divides into two -- the basic act of reproducing life -- the cellular environment must be exquisitely prepared. The exact timing and localization of the vast array of molecules and processes involved in duplicating chromosomes and separating the offspring from the parent is one of the basic wonders of biology and is at the core of both healthy living and diseases such as cancer, which arise when the process goes awry.

Now scientists at Rockefeller University have detailed the role of one protein, PRC1, that acts in the penultimate stage of cell division, helping to form the architectural structures, called central spindles, needed before the cell splits in two.

The findings expand the understanding of how these microtubules are fashioned into place. "In the absence of PRC1, the central spindle does not form, and that's a major problem, because then the cell doesn't divide," says Radhika Subramanian, lead author on the paper published by Cell in August. "So we wanted to know how PRC1 works, and now we've got a much better idea."

Scientists have known that PRC1, for "Protein Regular of Cytokines 1," is required in yeast, plants and humans for linking together the polymers that make up spindles, called microtubules, in a specific orientation. However, how PRC1 mediates microtubule binding and crosslinking was poorly understood. Subramanian, a postdoctoral fellow in Tarun Kapoor's Laboratory of Chemistry and Cell Biology, worked with Seth Darst's Laboratory of Molecular Biophysics to solve the atomic structure of the portion of PRC1 that interacts with microtubules using X-ray crystallography. The researchers determined that PRC1 binds microtubules through a domain which includes a structure called a spectrin fold. This is surprising, the scientists say, because it's a new role for the spectrin-fold, which has not been previously shown to mediate microtubule interactions.

Going further, the scientists, in collaboration with the laboratory of Ronald Milligan at the Scripps Institute, used electron microscopy to determine the structure of pairs of microtubules crosslinked by PRC1. A high resolution image revealed a defined crossbridge conformation of PRC1 which is attained only when the crosslinker is interacting with two microtubules. These structural features provide a model for how PRC1 achieves specific crosslinking of antiparallel microtubules.

PRC1 is a nonmotor protein, meaning it does not actively drive microtubules around the cell, but rather organizes their structure. (Another family of proteins, motor proteins, do the moving.) Subramanian and her colleagues set up an in vitro fluorescence microscopy based assay in which they could observe PRC1 activity as well as that of a motor protein on the same microtubule pair and found that PRC1 did not interfere with microtubule movements driven by motor proteins.

"So it doesn't act as a brake as was previously thought," Subramanian says. "By itself, it's capable of recognizing antiparallel overlaps regions in a dynamic, moving system, which is important. We think it could act as a mark that recruits other proteins to these specialized structures in cells."

That's one hypothesis Subramanian and colleagues want to explore next.


Story Source:

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


Journal Reference:

  1. Radhika Subramanian, Elizabeth M. Wilson-Kubalek, Christopher P. Arthur, Matthew J. Bick, Elizabeth A. Campbell, Seth A. Darst, Ronald A. Milligan, Tarun M. Kapoor. Insights into Antiparallel Microtubule Crosslinking by PRC1, a Conserved Nonmotor Microtubule Binding Protein. Cell, 2010; 142 (3): 433 DOI: 10.1016/j.cell.2010.07.012

Cite This Page:

Rockefeller University. "Key role for a protein in cell division described." ScienceDaily. ScienceDaily, 31 December 2010. <www.sciencedaily.com/releases/2010/12/101230103837.htm>.
Rockefeller University. (2010, December 31). Key role for a protein in cell division described. ScienceDaily. Retrieved April 21, 2014 from www.sciencedaily.com/releases/2010/12/101230103837.htm
Rockefeller University. "Key role for a protein in cell division described." ScienceDaily. www.sciencedaily.com/releases/2010/12/101230103837.htm (accessed April 21, 2014).

Share This



More Plants & Animals News

Monday, April 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Breakfast Foods Are Getting Pricier

Breakfast Foods Are Getting Pricier

AP (Apr. 21, 2014) Breakfast is now being served with a side of sticker shock. The cost of morning staples like bacon, coffee and orange juice is on the rise because of global supply problems. (April 21) Video provided by AP
Powered by NewsLook.com
Mich. Boy Unearths 10,000-Year-Old Mastodon Tooth

Mich. Boy Unearths 10,000-Year-Old Mastodon Tooth

Newsy (Apr. 20, 2014) A 9-year-old Michigan boy was exploring a creek when he came across a 10,000-year-old tooth from a prehistoric mastodon. Video provided by Newsy
Powered by NewsLook.com
Vermont Goat Meat Gives Refugees Taste of Home

Vermont Goat Meat Gives Refugees Taste of Home

AP (Apr. 18, 2014) Dairy farmers and ethnic groups in Vermont are both benefiting from a unique collaborative effort that's feeding a growing need for fresh and affordable goat meat. (April 18) Video provided by AP
Powered by NewsLook.com
Man Claims He Found Loch Ness Monster With... Apple Maps?

Man Claims He Found Loch Ness Monster With... Apple Maps?

Newsy (Apr. 18, 2014) Andy Dixon showed the Daily Mail a screenshot of what he believes to be the mythical beast swimming just below the lake's surface. 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