Navigation Links
Argonautes: A big turn-off for proteins

Johns Hopkins scientists believe they may have figured out how genetic snippets called microRNAs are able to shut down the production of some proteins.

The issue, they say, is important because the more scientists know about how genes the blueprints for proteins are regulated, the more likely they are to figure out how to use that information in treating or preventing diseases linked to such regulation, including cancer.

In both computer and test-tube studies using fruit-fly protein, the Johns Hopkins researchers intensively studied a fairly large protein called Argonaute because it is known to bind to microRNA and ultimately shut down protein production.

"The question was how it did it," says Rachel Green, Ph.D., a Howard Hughes Medical Institute investigator and professor of molecular biology and genetics in the Johns Hopkins University School of Medicine.

Previous studies have been inconclusive about the mechanism by which microRNAs bound to Argonautes prevent the production of protein from a given gene.

In this study, the team discovered that when an Argonaute binds to a microRNA, it then binds more tightly to a messenger RNA thereby sequestering the message from the translation machine known as the ribosome where protein production happens.

Their research appeared in January in Nature Structural & Molecular Biology.

The team set out to characterize Argonautes first using computers to compare their shapes and structures with other proteins. They found striking similarities between Argonaute structures and proteins that happened to exhibit a particular kind of "cooperative binding" known as allostery.

Allostery is a condition in which the binding of one molecule stimulates the binding of a second.

By chopping up Argonaute proteins from fruit flies and testing each piece individually, the team showed that allostery stimulated tenfold the binding of the Argonaute and miRNA complex to messenger RNA.

The scientists speculate that as a result of being bound, the messenger RNA was prevented from doing its job of delivering a gene's instructions to the ribosome that translates them and manufactures proteins. These studies provide new insights into Argonaute protein function, motivating the next series of questions in the field.

"MicroRNAs are all the rage," Green says. "Suddenly, in the last 10 years, there's this whole set of genes and cellular components that we had no idea existed, and they're ubiquitous. They play roles in all manner of development, and Argonautes are the main class of protein involved in regulating them."


Contact: Maryalice Yakutchik
Johns Hopkins Medical Institutions

Related biology news :

1. Membrane-coat proteins: Bacteria have them too
2. Researchers identify proteins that might contribute to memory loss and Alzheimers disease
3. Molecular chaperone keeps bacterial proteins from slow-dancing to destruction
4. BBS proteins shown to run an export business that protects cilia
5. Saliva proteins change as women age
6. Largest-ever database for liver proteins may lead to treatments for hepatitis
7. Escaped proteins add to hearing loss in elderly, UF researchers find
8. University of the Basque Country study on proteins related to Alzheimers
9. InVivo and CEVEC pharmaceuticals sign license agreement regarding the use of human CAP-T Technology for production of recombinant proteins
10. How proteins talk to each other
11. Researchers prolong the half-life of biopharmaceutical proteins
Post Your Comments:
(Date:4/28/2016)... -- First quarter 2016:   , Revenues ... first quarter of 2015 The gross margin was 49% ... and the operating margin was 40% (-13) Earnings per ... from operations was SEK 249.9 M (21.2) , Outlook ... 7,000-8,500 M. The operating margin for 2016 is estimated ...
(Date:4/15/2016)... April 15, 2016 Research ... Gait Biometrics Market 2016-2020,"  report to their offering.  ... ) , ,The global gait biometrics market is ... during the period 2016-2020. Gait analysis ... can be used to compute factors that are ...
(Date:3/29/2016)... 2016 LegacyXChange, Inc. (OTC: ... SelectaDNA/CSI Protect are pleased to announce our successful effort ... variety of writing instruments, ensuring athletes signatures against counterfeiting ... from athletes on LegacyXChange will be assured of ongoing ... Bill Bollander , CEO states, "By ...
Breaking Biology News(10 mins):
(Date:6/27/2016)... June 27, 2016  Global demand for enzymes ... through 2020 to $7.2 billion.  This market includes ... cleaning products, biofuel production, animal feed, and other ... and biocatalysts). Food and beverages will remain the ... increasing consumption of products containing enzymes in developing ...
(Date:6/27/2016)... ... June 27, 2016 , ... Parallel 6 , ... announced today the Clinical Reach Virtual Patient Encounter CONSULT module which enables ... the physician and clinical trial team. , Using the CONSULT module, patients and physicians ...
(Date:6/27/2016)... June 27, 2016   Ginkgo Bioworks , a ... engineering, was today awarded as one of the ... the world,s most innovative companies. Ginkgo Bioworks is ... the real world in the nutrition, health and ... directly with customers including Fortune 500 companies to ...
(Date:6/24/2016)... ... 24, 2016 , ... Researchers at the Universita Politecnica delle Marche in Ancona ... or pleural mesothelioma. Their findings are the subject of a new article on the ... are signposts in the blood, lung fluid or tissue of mesothelioma patients that can ...
Breaking Biology Technology: