Featured Research

from universities, journals, and other organizations

Researchers Uncover Critical Player In Cell Communication

Date:
October 6, 2006
Source:
Johns Hopkins Medical Institutions
Summary:
Johns Hopkins researchers have teased out the function of a protein implicated in Williams-Beuren syndrome, a rare cognitive disorder associated with overly social behavior and lack of spatial awareness. Called TFII-I, or TF "two eye," the protein long known to help control a cell's genes also controls how much calcium a cell takes in, a function critical for all cells, including nerves in the brain. The study will be published this week in Science.

Johns Hopkins researchers have teased out the function of a protein implicated in Williams-Beuren syndrome, a rare cognitive disorder associated with overly social behavior and lack of spatial awareness. Called TFII-I, or TF "two eye," the protein long known to help control a cell's genes also controls how much calcium a cell takes in, a function critical for all cells, including nerves in the brain. The study will be published this week in Science.

"While the previously described function of TFII-I very well also could contribute to the cognitive defects of Williams-Beuren syndrome, its role controlling calcium makes much more sense," says Stephen Desiderio, M.D., Ph.D., a professor of molecular biology and genetics and director of the Institute of Basic Biomedical Sciences at Hopkins. And, says Desiderio, others have shown that defects in a cell's ability to take in calcium can lead to other neurological and behavioral conditions.

Williams-Beuren syndrome is associated with craniofacial defects, problems with the aorta and a very specific mental retardation that causes those affected to be talkative, sociable and empathetic but at the same time have significant spatial learning defects. Those affected are highly expressive, have exceptionally strong language abilities and "can talk up a storm," for example. But at the same time, they are poor at global organization, having problems re-creating patterns in drawings. The syndrome occurs in roughly one in 25,000 births and is caused by a deletion of a small section of chromosome 7 that contains several genes, including the gene that encodes the TFII-I protein.

The discovery came after Desiderio and his team used biochemical "bait" to fish for candidate proteins that physically bind to TFII-I. The fishing expedition returned one protein known to control when and how much calcium a cell takes in.

"The partner we found in the fishing experiment and the abundance of TFII-I outside the cell nucleus led us to suspect that this protein must be doing more than regulate gene expression," says Desiderio.

Under normal conditions, calcium does not flow freely into and out of cells until a demand for it - such as a muscle contraction or nerve function -- triggers cells to take up the free floating element from their surroundings. Cells store calcium until still other signals occur to release it again.

"The finding was stunning to us because calcium is one of the most important messengers in cells," says Desiderio, "and both it and TFII-I are in every cell. That affirmed our suspicion that TFII-I could be doing something important with calcium signaling."

In one experiment, the Hopkins team knocked down the amount of TFII-I in lab-grown cells and looked for changes in calcium flow under a high-power microscope using a dye that glows when it comes in contact with calcium. A camera attached to the microscope recorded the brightness of the glow and fed that measure into a computer that calculates the amount of calcium.

Knocking down TFII-I and separately assaulting the cells with chemicals caused the cells to take up more calcium than usual.

The researchers realized that when they depleted the cells of TFII-I, the cell responded by installing more calcium channels in their surfaces that allow calcium and only calcium to enter the cell. "We think TFII-I must control calcium entry into the cell by somehow limiting the number of calcium channels at the cell's surface," says Desiderio.

"There's good evidence suggesting that the frequency and intensity of this ebb and flow of calcium can determine a cell's response to external cues," says Desiderio. "TFII-I may be a universal player in communication between cells, in the brain, the immune system and elsewhere."

The researchers were funded by the Howard Hughes Medical Institute, the National Cancer Institute and the Institute for Cell Engineering at Hopkins.

Authors on this paper are Gabriela Caraveo, Damian van Rossum, Randen Patterson, Solomon Snyder and Desiderio, all of Hopkins.


Story Source:

The above story is based on materials provided by Johns Hopkins Medical Institutions. Note: Materials may be edited for content and length.


Cite This Page:

Johns Hopkins Medical Institutions. "Researchers Uncover Critical Player In Cell Communication." ScienceDaily. ScienceDaily, 6 October 2006. <www.sciencedaily.com/releases/2006/10/061006072441.htm>.
Johns Hopkins Medical Institutions. (2006, October 6). Researchers Uncover Critical Player In Cell Communication. ScienceDaily. Retrieved September 1, 2014 from www.sciencedaily.com/releases/2006/10/061006072441.htm
Johns Hopkins Medical Institutions. "Researchers Uncover Critical Player In Cell Communication." ScienceDaily. www.sciencedaily.com/releases/2006/10/061006072441.htm (accessed September 1, 2014).

Share This




More Health & Medicine 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
Liberia Continues Fight Against Ebola

Liberia Continues Fight Against Ebola

AFP (Aug. 30, 2014) Authorities in Liberia try to stem the spread of the Ebola epidemic by raising awareness and setting up sanitation units for people to wash their hands. Duration: 00:41 Video provided by AFP
Powered by NewsLook.com
California Passes 'yes-Means-Yes' Campus Sexual Assault Bill

California Passes 'yes-Means-Yes' Campus Sexual Assault Bill

Reuters - US Online Video (Aug. 30, 2014) California lawmakers pass a bill requiring universities to adopt "affirmative consent" language in their definitions of consensual sex, part of a nationwide drive to curb sexual assault on campuses. Linda So reports. Video provided by Reuters
Powered by NewsLook.com
New Drug Could Reduce Cardiovascular Deaths

New Drug Could Reduce Cardiovascular Deaths

Newsy (Aug. 30, 2014) The new drug from Novartis could reduce cardiovascular deaths by 20 percent compared to other similar drugs. 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