Navigation Links
Molecular fossil
Date:11/14/2010

In today's world of sophisticated organisms proteins are the stars. They are the indispensible catalytic workhorses, carrying out the processes essential to life. But long, long ago ribonucleic acid (RNA) reigned supreme.

Now Northwestern University researchers have produced an atomic picture that shows how two of these very old molecules interact with each other. It is a rare glimpse of the transition from an ancient, RNA-based world to our present, protein-catalyst dominated world.

The scientists are the first to show the atomic details of how ribonuclease P (RNase P) recognizes, binds and cleaves transfer RNA (tRNA). They used the powerful X-rays produced by the Advanced Photon Source at Argonne National Laboratory to obtain images from crystals formed by these two RNA molecules. The result is a snapshot of one of the most complex models of a catalytic RNA and its target.

Details of the structure will be published Nov. 14 by the journal Nature.

"RNA is an ancient molecule, but it is pretty sophisticated," said Alfonso Mondragn, professor of molecular biosciences in the Weinberg College of Arts and Sciences. He led the research. "Our crystal structure shows that it has many of the properties we ascribe to modern molecules. RNA is a catalyst that has much of the versatility and complexity of modern-day proteins."

For billions of years and still to this day, the function of RNase P -- found in nearly all organisms, from bacteria to humans -- has been to cleave transfer tRNA. If the tRNA is not cleaved, it is not useful to the cell.

"We knew this important chemistry happened, that RNA acts as a catalyst, but we didn't know exactly how until now," Mondragn said. "We now have a better understanding of how RNA works."

RNase P is formed by a large RNA core plus a small protein, illustrating the evolutionary shift from an RNA world toward a protein-dominated world. The protein helps recognize the tRNA, but most of the recognition occurs through RNA-RNA interactions involving shape complementarity and also base pairing.

The structure shows that once RNase P recognizes tRNA, it docks and, assisted by metal ions, cuts one chemical bond. This matures the tRNA, producing a smaller RNA molecule that now can contribute to fundamental processes in the cell. The RNA-based enzyme does this over and over, cutting each tRNA in exactly the same place every time.

"The discovery nearly 30 years ago that RNA molecules can have a catalytic function raised the idea that maybe RNA was the first molecule," Mondragn said. "Our work reinforces this notion of the existence of an RNA world when life first began."


'/>"/>

Contact: Megan Fellman
fellman@northwestern.edu
847-491-3115
Northwestern University
Source:Eurekalert

Related biology news :

1. SNM releases new fact sheet on breast cancer and molecular imaging
2. Genetic Engineering & Biotechnology News reports on growing role of molecular diagnostics
3. A new journal where molecular biology meets clinical research
4. Scientists trace molecular origin of proportional development
5. New molecular insight into vertebrate brain development
6. Plants display molecular amnesia
7. Pitt, NETL researchers report molecular chain reaction thought to be impossible
8. Tracking the molecular pathway to mixed-lineage leukemia
9. Researchers compile molecular manual for 100s of inherited diseases
10. Biologists learn structure, mechanism of powerful molecular motor in virus
11. Phoenix conference highlights TGens and Scottsdale Healthcares contributions to molecular oncology
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/15/2016)... , June 15, 2016 ... report titled "Gesture Recognition Market by Application Market - Global Industry ... - 2024". According to the report, the  global gesture ... in 2015 and is estimated to grow at ... billion by 2024.  Increasing application of ...
(Date:6/9/2016)... , June 9, 2016 ... Police deploy Teleste,s video security solution to ensure the safety ... France during the major tournament Teleste, ... communications systems and services, announced today that its video security ... to back up public safety across the country. ...
(Date:6/3/2016)... LONDON , June 3, 2016 /PRNewswire/ ... Transport Management) von Nepal ... ,Angebot und Lieferung hochsicherer geprägter Kennzeichen, einschließlich ... weltweit führend in der Produktion und Implementierung ... an der Ausschreibung im Januar teilgenommen, aber ...
Breaking Biology News(10 mins):
(Date:6/23/2016)... SILVER SPRING, Md. , June 23, 2016 ... evidence collected from the crime scene to track the criminal ... sick, and the U.S. Food and Drug Administration (FDA) uses ... Sound far-fetched? It,s not. ... whole genome sequencing to support investigations of foodborne illnesses. Put ...
(Date:6/23/2016)... , June 23, 2016   EpiBiome , a ... $1 million in debt financing from Silicon Valley Bank ... automation and to advance its drug development efforts, as ... facility. "SVB has been an incredible strategic ... services a traditional bank would provide," said Dr. ...
(Date:6/23/2016)... BEACH, Calif. , June 23, 2016  Blueprint ... new biological discoveries to the medical community, has closed ... co-founder Matthew Nunez . "We have ... us with the capital we need to meet our ... will essentially provide us the runway to complete validation ...
(Date:6/23/2016)... ... June 23, 2016 , ... Velocity ... intelligent tools designed, tuned and optimized exclusively for Okuma CNC machining centers at ... result of a collaboration among several companies with expertise in toolholding, cutting tools, ...
Breaking Biology Technology: