Navigation Links
First major study of mammalian 'disorderly' proteins

Investigators at St. Jude Children's Research Hospital turned up the heat on "disorderly" proteins and confirmed that most of these unruly molecules perform critical functions in the cell. The St. Jude team completed the first large-scale collection, investigation and classification of these so-called intrinsically unstructured proteins (IUPs), a large group of molecules that play vital roles in the daily activities of cells.

The new technique for collecting and identifying IUPs is important because although scientists have been aware of the existence of flexible proteins for many years, they have only recently realized that these molecules play major biological roles in the cell, according to Richard Kriwacki, Ph.D., an associate member of the St. Jude Department of Structural Biology. Moreover, he said, previous work by other researchers suggested that a large proportion of IUPs in mammalian cells play key roles in transmitting signals and coordinating biochemical and genetic activities that keep the cell alive and functioning. Kriwacki is senior author of a report on this work that appears in the prepublication online issue of Journal of Proteome Research.

"Until now there was no way to separate IUPs in large numbers from the more structured proteins and confirm their roles in the cell," Kriwacki said. "Our new technique selectively concentrates the IUPs that are involved in regulating functions in the cell and transmitting signals within them."

Unlike the classic description of proteins described in science textbooks, IUPs are not completely locked into rigid, 3-D shapes that determine their function in the cell. Instead, IUPs have varying amounts of flexibility within their sometimes spaghetti-like structures that is critical for function. For example, one protein named p27 initially looks like a SlinkyTM toy. However, when p27 goes to work, it puts a vise-like grip on an enzyme that otherwise would promote uncontrolle d cell division.

The St. Jude team developed a technique that uses heat to isolate IUPs in large, purified quantities from extracts of a standard type of cultured mouse cells called NIH3T3 fibroblasts. The IUPs were resistant to the heat, unlike more structured proteins, which fell apart. Based on these studies, the investigators were able to classify all proteins into one of three categories: IUPs; intrinsically folded proteins (IFPs, i.e., fully folded into specific shapes); or mixed ordered or disordered proteins (MPs), which have both structured and unstructured parts.

"This work further illustrates that the disorderliness of IUPs isn't just a curiosity," said Charles Galea, Ph.D., a postdoctoral fellow in Kriwacki's lab. "This characteristic is a fundamental part of how these proteins work. So determining their exact nature, including the parts that are disordered, is an important part of understanding how they work. This is especially important in the case of IUPs linked to cancer and other diseases." The paper's first author, Galea, did much of the work on this project.


Source:St. Jude Children's Research Hospital

Related biology news :

1. Timing is everything: First step in protein building revealed
2. Emory Eye Center Implants Its First Retinal Chips In Patients With Retinitis Pigmentosa
3. First atlas of key brain genes could speed research on cancer, neurological diseases
4. First-ever Compounds To Target Only Metastatic Cells Are Highly Effective Against Breast, Prostate, And Colon Cancers
5. NYCs First Rapid HIV Drug-resistant AIDS Case Prompts Call to Step Up HIV Prevention
6. First real-time view of developing neurons reveals surprises, say Stanford researchers
7. Breast-Cancer Risk Linked to Exposure to Traffic Emissions at Menarche, First Birth
8. Mayo Clinic Researchers Create Obedient Virus; First Step To Use Measles Virus Against Cancer
9. First frozen egg baby born in Canada
10. Human Cells Filmed Instantly Messaging for First Time
11. First North American Encapsulated Islet Transplant without Long-term Immune Suppression into a Patient with Type 1 Diabetes
Post Your Comments:

(Date:11/18/2015)... , November 18, 2015 ... published a new market report titled  Gesture Recognition Market ... Forecast, 2015 - 2021. According to the report, the global gesture ... is anticipated to reach US$29.1 bn by 2021, at ... North America dominated the global ...
(Date:11/17/2015)... Nov. 17, 2015  Vigilant Solutions announces today that ... Board of Directors. --> ... retiring from the partnership at TPG Capital, one of ... over $140 Billion in revenue.  He founded and led ... the TPG companies, from 1997 to 2013.  In his ...
(Date:11/12/2015)... Nov. 12, 2015  A golden retriever that stayed ... dystrophy (DMD) has provided a new lead for treating ... the Broad Institute of MIT and Harvard and the ... . Cell, pinpoints a protective ... the disease,s effects. The Boston Children,s lab of ...
Breaking Biology News(10 mins):
(Date:11/25/2015)... , Nov. 25, 2015  Neurocrine Biosciences, Inc. (Nasdaq: ... , President and CEO of Neurocrine Biosciences, will be ... in New York . ... the website approximately 5 minutes prior to the presentation ... of the presentation will be available on the website ...
(Date:11/25/2015)... PORTLAND, Oregon , November 25, 2015 /PRNewswire/ ... Deep Market Research Report is a professional and ... Genomics industry.      (Logo: ... basic overview of the industry including definitions, classifications, ... analysis is provided for the international markets including ...
(Date:11/24/2015)... SUNNYVALE, Calif. , Nov. 24, 2015 ... executives will be speaking at the following conference, and ... New York, NY      Tuesday, December 1, ... New York, NY      Tuesday, December 1, ...      Piper Jaffray Healthcare Conference, New York, NY ...
(Date:11/24/2015)... Florida (PRWEB) , ... November 24, 2015 , ... ... biggest event of the year and one of the premier annual events for ... and ran from 8–11 November 2015, where ISPE hosted the largest number of ...
Breaking Biology Technology: