Featured Research

from universities, journals, and other organizations

Changing Colors In Mice: Gene Turned On And Off At Will Through Simple Dietary Change

Date:
June 19, 2001
Source:
Cold Spring Harbor Laboratory
Summary:
As published in Genes & Development, researchers from the University of Virginia have developed a new and powerful transgenic mouse model system. This system allows scientists to introduce a foreign gene into the mouse and turn this gene on and off at will through a simple dietary change.

As published in Genes & Development, researchers from the University of Virginia have developed a new and powerful transgenic mouse model system. This system allows scientists to introduce a foreign gene into the mouse and turn this gene on and off at will through a simple dietary change. The paper details the careful genetic manipulation behind this work and the eye-catching results – mice that change color when a special supplement is added to their drinking water, and revert back to their original color once the supplement is removed!

Dr. Scrable and colleagues genetically engineered the bacterial lac operon for use as an inducible gene regulatory system in the mouse. The lac regulatory system in the mouse provides tight, reversible control of specific gene expression – a tool that will be of wide interest to those who model human disease and development.

The lac operon in E. coli consists of a set of regulatory elements and structural genes whose products enable the bacterial cell to metabolize lactose. In the absence of lactose, lac structural genes are not transcribed because the lac repressor protein is bound to the lac operator, thereby preventing RNA polymerase from initiating transcription. When the lactose analog IPTG is present, the lac repressor protein binds IPTG and undergoes a conformational change that decreases its affinity for the lac operator and allows for transcription to occur. Dr. Scrable and colleagues have spent the past four years adapting this bacterial operon for use as a gene regulatory system in the mouse.

Dr. Scrable and colleagues manipulated the DNA sequence and gene structure of the lac repressor protein so that it is expressed ubiquitously in the mouse. By strategically integrating lac operator sequences within the promoter of a reporter gene, tyrosinase, Dr. Scrable and colleagues generated a mouse strain that expresses tyrosinase only in the presence of IPTG. As tyrosinase encodes an enzyme necessary for coat color, their experiments had startling results.

Dr. Scrable and colleagues demonstrated that tyrosinase is repressed in the absence of IPTG, causing mice to develop as purely white albinos. When IPTG is added to the drinking water, tyrosinase is activated and the coat color changes to brown. However, once IPTG is depleted, tyrosinase is again turned off and the albino phenotype returns. Interestingly, these effects occur in both adult mice and in embryos that are exposed to IPTG via the mother’s drinking water.

The IPTG inducible system developed by Dr. Scrable and colleagues represents a marked advance in mammalian model systems. Although further analysis is needed before all features of the system are fully realized, Dr. Alea Mills, an expert in this field, remarked that this system "appears to fulfill the criteria for an optimal inducible system." As the mouse is the most widely used experimental system to model human disease and development, this revolutionary new system will greatly broaden the range of biological questions that scientists can address experimentally.


Story Source:

The above story is based on materials provided by Cold Spring Harbor Laboratory. Note: Materials may be edited for content and length.


Cite This Page:

Cold Spring Harbor Laboratory. "Changing Colors In Mice: Gene Turned On And Off At Will Through Simple Dietary Change." ScienceDaily. ScienceDaily, 19 June 2001. <www.sciencedaily.com/releases/2001/06/010615071124.htm>.
Cold Spring Harbor Laboratory. (2001, June 19). Changing Colors In Mice: Gene Turned On And Off At Will Through Simple Dietary Change. ScienceDaily. Retrieved July 29, 2014 from www.sciencedaily.com/releases/2001/06/010615071124.htm
Cold Spring Harbor Laboratory. "Changing Colors In Mice: Gene Turned On And Off At Will Through Simple Dietary Change." ScienceDaily. www.sciencedaily.com/releases/2001/06/010615071124.htm (accessed July 29, 2014).

Share This




More Plants & Animals News

Tuesday, July 29, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Rodents Rampant in Gardens Around Louvre

Rodents Rampant in Gardens Around Louvre

AP (July 29, 2014) Food scraps and other items left on the grounds by picnickers brings unwelcome visitors to the grounds of the world famous and popular Louvre Museum in Paris. (July 29) Video provided by AP
Powered by NewsLook.com
Deadly Ebola Virus Threatens West Africa

Deadly Ebola Virus Threatens West Africa

AP (July 28, 2014) West African nations and international health organizations are working to contain the largest Ebola outbreak in history. It's one of the deadliest diseases known to man, but the CDC says it's unlikely to spread in the U.S. (July 28) Video provided by AP
Powered by NewsLook.com
Traditional African Dishes Teach Healthy Eating

Traditional African Dishes Teach Healthy Eating

AP (July 28, 2014) Classes are being offered nationwide to encourage African Americans to learn about cooking fresh foods based on traditional African cuisine. The program is trying to combat obesity, heart disease and other ailments often linked to diet. (July 28) Video provided by AP
Powered by NewsLook.com
Asteroid's Timing Was 'Colossal Bad Luck' For The Dinosaurs

Asteroid's Timing Was 'Colossal Bad Luck' For The Dinosaurs

Newsy (July 28, 2014) The asteroid that killed the dinosaurs struck at the worst time for them. A new study says that if it hit earlier or later, they might've survived. 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