Featured Research

from universities, journals, and other organizations

First 3-D Images Obtained Of Core Component Of Molecular Machinery Used For Cell Reproduction

Date:
December 23, 2008
Source:
Vanderbilt University
Summary:
For the first time, structural biologists have managed to obtain the detailed three-dimensional structure of one of the proteins that form the core of the complex molecular machine, called the replisome, that plant and animal cells assemble to copy their DNA as the first step in cell reproduction.

Mcm10 is shown in a surface view interacting with a single strand of DNA depicted in red. Mcm10 contains two classic binding scaffolds. One is an OB-fold (OB stands for oligonucleotide/oligosaccharide) shown in green. The other is a structure called a zinc finger shown in blue. Proteins typically use OB-folds to interact with single-stranded DNA, while zinc fingers are used normally to recognize double-stranded DNA segments.
Credit: Brandt Eichman

For the first time, structural biologists have managed to obtain the detailed three-dimensional structure of one of the proteins that form the core of the complex molecular machine, called the replisome, that plant and animal cells assemble to copy their DNA as the first step in cell reproduction.

The molecular structure of the protein, Mcm10, was published online by the journal Structure on Dec. 9. Its discovery was a collaborative effort by Brandt Eichman, assistant professor of biological sciences at Vanderbilt University, and Walter Chazin, Chancellor's Professor of Biochemistry and Physics at Vanderbilt, working with Anja Katrin-Bielinsky at the University of Minnesota.

Currently, the process of DNA replication in eukaryote cells – cells that have their genetic information contained in a nucleus – is a "black box." Biologists know what goes in and what comes out but they know very little about how the process actual works at the molecular level. Because form causes function in the protein world, determining the 3D structure of the 30-40 proteins that combine to form the replisome is a necessary first step to figuring out the details of this critical process and understanding how it can go wrong.

The structure of Mcm10 was determined using cells from the African clawed frog (Xenopus laevis); the structures of analogous proteins in human and other animal cells should be nearly identical, the researchers maintain. The Mcm10 structure reveals a special feature, called the OB-fold, that proteins use to interact with single-stranded DNA and a series of three loops that the researchers believe are used to clamp down on the DNA. The protein also contains a protrusion – called a zinc finger because it is built around a zinc atom – that proteins normally use to recognize specific double-stranded DNA segments. In this case the zinc finger appears to be modified in a way that allows it to detect generic DNA.

The researchers think that Mcm10 may play a role in positioning the other proteins in the replisome onto the single DNA strand so that it may be correctly read and duplicated, while acknowledging that they have very little information about how it functions.

The research was funded in part by a grant from the National institutes of Health.


Story Source:

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


Cite This Page:

Vanderbilt University. "First 3-D Images Obtained Of Core Component Of Molecular Machinery Used For Cell Reproduction." ScienceDaily. ScienceDaily, 23 December 2008. <www.sciencedaily.com/releases/2008/12/081209125822.htm>.
Vanderbilt University. (2008, December 23). First 3-D Images Obtained Of Core Component Of Molecular Machinery Used For Cell Reproduction. ScienceDaily. Retrieved September 1, 2014 from www.sciencedaily.com/releases/2008/12/081209125822.htm
Vanderbilt University. "First 3-D Images Obtained Of Core Component Of Molecular Machinery Used For Cell Reproduction." ScienceDaily. www.sciencedaily.com/releases/2008/12/081209125822.htm (accessed September 1, 2014).

Share This




More Plants & Animals News

Monday, September 1, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

We've Got Mites Living In Our Faces And So Do You

We've Got Mites Living In Our Faces And So Do You

Newsy (Aug. 30, 2014) A new study suggests 100 percent of adult humans (those over 18 years of age) have Demodex mites living in their faces. Video provided by Newsy
Powered by NewsLook.com
Washington Wildlife Center Goes Nuts Over Baby Squirrels

Washington Wildlife Center Goes Nuts Over Baby Squirrels

Reuters - US Online Video (Aug. 30, 2014) An animal rescue in Washington state receives an influx of orphaned squirrels, keeping workers busy as they nurse them back to health. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com
Experimental Ebola Drug ZMapp Cures Lab Monkeys Of Disease

Experimental Ebola Drug ZMapp Cures Lab Monkeys Of Disease

Newsy (Aug. 29, 2014) In a new study, a promising experimental treatment for Ebola managed to cure a group of infected macaque monkeys. Video provided by Newsy
Powered by NewsLook.com
Killer Amoeba Found in Louisiana Water System

Killer Amoeba Found in Louisiana Water System

AP (Aug. 28, 2014) State health officials say testing has confirmed the presence of a killer amoeba in a water system serving three St. John the Baptist Parish towns. (Aug. 28) Video provided by AP
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