Navigation Links
Master gene plays key role in blood sugar levels
Date:11/27/2008

When mice that lack steroid receptor-2 (SRC-2) a master regulator gene called a coactivator fast for a day, their blood sugar levels plummet. If they go another day without food, they will die.

The severity of the hypoglycemia (low blood sugar) was unexpected, said Dr. Bert W. O'Malley, chair of molecular and cellular biology at Baylor College of Medicine and senior author of the report on the study that appears in the current issue of the journal Science. Normal mice live as long as seven days without food.

Further examination showed that the lack of SRC-2 prevents an important enzyme from converting sugar stored in the liver into a form that can go into the bloodstream. The finding has implications for a genetic disease called Von Gierke's disease and potentially adult-onset diabetes.

The symptoms suffered by mice resembled those of children born with Von Gierke's disease, said O'Malley. The disorder can create serious problems unless it is recognized early. Parents must wake the infants every few hours and feed them to keep their blood glucose levels up. As long as the glucose levels are high enough, the brain is nourished. If their blood glucose levels drop below a certain level, they suffer seizures, lose consciousness and can die.

Studies in O'Malley's laboratory in collaboration with researchers from Duke University Medical Center in Durham, N.C., revealed that SRC-2 works with an orphan nuclear receptor ROR alpha to affect the activity of the sugar-converting enzyme, glucose-6-phosphatase in the liver.

The liver produces 90 percent of the glucose circulating in the blood stream. Glucose stored in the liver has a phosphate molecular attached to it. This phosphorylated glucose cannot leave the liver until the enzyme removes the phosphate molecule. SRC-2 is critical to that removal process.

If the sugar cannot leave the liver, it remains there in the form of glycogen. Eventually, the buildup of this storage form of sugar can cause the liver to fail.

"It's one of the few examples of a metabolic genetic disease that can be created by a deficiency in a coactivator," O'Malley said.

He actually identified the first coactivator SRC-1. His work with another called SRC-3 has led to better understanding of cancer and inflammation and led to the understanding of drugs such as tamoxifen in the treatment of breast cancer.

"This again shows that these coactivators are important master genes for physiology," said O'Malley. "In the case of SRC-3, if there is too much, you get cancer. Here, if you get too little SRC-2, you can't maintain your blood sugar levels."

He believes that potentially too much SRC-2 could raise the levels of glucose in the blood. That would call for increased production of insulin. Often, the pancreas fails after being forced to produce continuous, high levels of insulin. This can result in adult-onset diabetes.

O'Malley and his colleagues plan to start studying the activity in humans in the near future. Eventually, he hopes they can find ways to target the activity of SRC-2 with a drug.


'/>"/>

Contact: Kimberlee Norton
kknorton@bcm.edu
713-798-4710
Baylor College of Medicine
Source:Eurekalert

Related biology news :

1. Bits of junk RNA aid master tumor-suppressor gene
2. Master Lock(R) smartTOUCH(TM) Garage Door Opener to be Featured on Hispanic Network Radio Weekend Show
3. McMaster University engineering professor receives Humboldt Research Award
4. New master switch found in the brain that regulates appetite and reproduction
5. New book helps medical students master clinical skills
6. Speed plays crucial role in breaking proteins H-bonds
7. Small RNA plays parallel roles in bacterial metabolism
8. Moss protein plays role in Alzheimers disease
9. Early parenting plays key role in infants physiological response to stress
10. Protein identified that plays role in blood flow
11. Study finds genetic variant plays role in cleft lip
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:5/9/2016)... May 9, 2016 Elevay is ... to expanding freedom for high net worth professionals seeking ... today,s globally connected world, there is still no substitute ... ever duplicate sealing your deal with a firm handshake. ... by taking advantage of citizenship via investment programs like ...
(Date:4/26/2016)... -- Research and Markets has announced the ...  report to their offering.  , ,     (Logo: ... forecast the global multimodal biometrics market to grow ... 2016-2020.  Multimodal biometrics is being implemented ... healthcare, BFSI, transportation, automotive, and government for controlling ...
(Date:4/13/2016)... physicians supporting Medicaid patients in Central Florida ... telehealth thanks to a new partnership with higi.   ... can routinely track key health measurements, such as blood ... they opt in, share them with IMPOWER clinicians through ... location at no cost. By leveraging this data, IMPOWER ...
Breaking Biology News(10 mins):
(Date:6/27/2016)... , June 27, 2016   Ginkgo Bioworks , ... industrial engineering, was today awarded as one of ... of the world,s most innovative companies. Ginkgo Bioworks ... for the real world in the nutrition, health ... work directly with customers including Fortune 500 companies ...
(Date:6/24/2016)... , ... June 24, 2016 , ... Researchers at the ... commonly-identified miRNAs in people with peritoneal or pleural mesothelioma. Their findings are the subject ... it now. , Diagnostic biomarkers are signposts in the blood, lung fluid or ...
(Date:6/23/2016)... June 23, 2016 /PRNewswire/ - FACIT has announced ... biotechnology company, Propellon Therapeutics Inc. ("Propellon" ... commercialization of a portfolio of first-in-class WDR5 inhibitors ... such as WDR5 represent an exciting class of ... precision medicine for cancer patients. Substantial advances have ...
(Date:6/23/2016)... Prostate Cancer Foundation (PCF) is pleased to announce 24 new Young Investigator ... Members of the Class of 2016 were selected from a pool of 128 ... About the Class of 2016 PCF Young Investigators ... ... ...
Breaking Biology Technology: