Navigation Links
Notch-ing glucose into place
Date:1/27/2008

A novel gene called rumi regulates Notch signaling by adding a glucose molecule to the part of the Notch protein that extends outside a cell, said researchers from Baylor College of Medicine in Houston and Stony Brook University in New York in a report that appears today in the journal Cell.

Cellular signaling governed by the Notch protein determines cell fate determination and differentiation.

The complete loss of rumi causes a temperature-dependent defect in Notch signaling, an unusual phenomenon said Dr. Hugo Bellen, professor of molecular and human genetics at BCM and director of the program in developmental biology. He is also a Howard Hughes Medical Institute investigator.

Bellen and his colleagues discovered the genes effect on bristles in the fruit fly. These bristles are external sensory organs that can be easily screened for changes involved in Notch signaling. Indeed, loss of Notch signaling causes loss of these external sensory organs. Fruit flies that lack the rumi protein have a higher than normal density of bristles on the thorax, indicating a subtle loss of Notch activity. However, at 25 degrees C, the bristles are lost, which suggests a severe loss of Notch signaling.

The activity of the Notch receptor needs to be inactivated in one cell to allow it to become different from the other daughter cell, and this process is used reiteratively in many consecutive cell divisions. For example, if Notch is activated inappropriately in cells of the blood lineage, it will cause leukemia in humans, said Bellen.

It is also a key gene to specify neurons in the peripheral and central nervous system, said Bellen. When embryos lack a functional Notch protein, they have far too many neurons. The same phenomenon can be observed in rumi mutant embryos.

In animals with mutated rumi, the Notch protein accumulates in the membrane and fails to become activated. Similarities between rumi and some sugar-modifying enzymes involved in a particular process in the yeast Cryptococcus neoformans prompted Bellen to ask if loss of rumi affects the manner in which glucose molecules are added to the Notch protein.

He and his colleagues found that some sugars are not added to the Notch protein in rumi-mutant animals. This finding led to further experiments that demonstrated that the protein associated with rumi is a type of enzyme called an O-glycosyltransferase.

The Notch protein crosses the cellular membrane, with part inside the cell and part outside. The outer portion of Notch contains amino acid repeats that are similar to epidermal growth factor. Rumi is involved in adding a sugar to certain areas of these repeats.

Bellen said, The sugars play a crucial role to ensure that Notch is folded properly and that it can be cleaved at the cell membrane. If cleavage does not occur, there is no Notch signaling. Rumi is the first protein identified that can transfer glucose to proteins directly.


'/>"/>

Contact: Glenna Picton
picton@bcm.edu
713-798-4710
Baylor College of Medicine
Source:Eurekalert

Related medicine news :

1. Scientists explain how insulin secreting cells maintain their glucose sensitivity
2. Once-Weekly Exenatide Showed Statistical Superiority in Glucose Control Compared to BYETTA in Head-to-Head Study
3. Increased glucose level is a strong risk factor for colorectal cancer
4. Got sugar? Glucose affects our ability to resist temptation
5. Monotherapy BYETTA(R) Showed Significant Improvement in Glucose Control and Weight Loss in Adults with Type 2 Diabetes
6. MultiVu Video Feed: WELCHOL (R) (COLESEVELAM HCL) RECEIVES FDA APPROVAL FOR GLUCOSE CONTROL IN ADULTS WITH TYPE 2 DIABETES MELITUS
7. Welchol(TM) (colesevelam HCl) Receives FDA Approval to Reduce Blood Glucose in Adults with Type 2 Diabetes
8. NYC-area 1st: Morgan Stanley Childrens Hospital performs transcatheter pulmonary valve replacement
9. IRIDEX Announces Closing of $5.0 Million Private Placement
10. Academy releases emergency preparedness tools to enable millions more people to shelter in place
11. Pill Equals Injection in Preventing Clots After Hip Replacement
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/26/2016)... ... June 26, 2016 , ... On June 10-11, 2016, A ... 2016 Cereal Festival and World’s Longest Breakfast Table in Battle Creek, MI, where the ... history as home to some of the world’s leading providers of cereal and other ...
(Date:6/25/2016)... , ... June 25, 2016 , ... ... policy issues and applications at AcademyHealth’s Annual Research Meeting June 26-28, 2016, at ... on several important health care topics including advance care planning, healthcare costs and ...
(Date:6/25/2016)... (PRWEB) , ... June 25, 2016 , ... As a ... Magna Cum Laude and his M.D from the David Geffen School of Medicine at ... returned to Los Angeles to complete his fellowship in hematology/oncology at the UCLA-Olive View-Cedars ...
(Date:6/24/2016)... ... ... Those who have experienced traumatic events may suffer from a complex set of ... or alcohol abuse, as a coping mechanism. To avoid this pain and suffering, Serenity ... event. , Trauma sufferers tend to feel a range of emotions, from depression, guilt, ...
(Date:6/24/2016)... ... June 24, 2016 , ... Dr. Amanda Cheng, an ... Cheng has extensive experience with all areas of orthodontics, including robotic Suresmile technology, ... , Micro-osteoperforation is a revolutionary adjunct to orthodontic treatment. It can be ...
Breaking Medicine News(10 mins):
(Date:6/24/2016)... June 24, 2016 Research ... "Structural Electronics 2015-2025: Applications, Technologies, Forecasts" ... In-Mold Electronics, Smart Skin, Structural Health ... Structural electronics involves electronic and/or electrical ... structures, replacing dumb structures such as vehicle bodies ...
(Date:6/24/2016)... Research and Markets has announced the addition of ... report to their offering. ... The World Market for Companion Diagnostics covers the world market ... the report includes the following: , World ... Region (N. America, EU, ROW), 2015-2020 , World IVD ...
(Date:6/24/2016)... , June 24, 2016  Arkis BioSciences, ... less invasive and more durable cerebrospinal fluid treatments, ... funding.  The Series-A funding is led by Innova ... Fund, and other private investors.  Arkis, new financing ... instrumentation and the market release of its in-licensed ...
Breaking Medicine Technology: