Featured Research

from universities, journals, and other organizations

Glimpse of how the 'code' of life may have emerged

Date:
March 24, 2011
Source:
University of California - Santa Barbara
Summary:
A portion of the "code" of life has been unraveled by a graduate student. She aimed to decipher intramolecular communication within a large RNA-protein enzyme responsible for expressing the genetic code for the amino acid glutamine. To her surprise, the experiments captured a partial glimpse of how the genetic coding of life may have emerged.

Crystal structure of glutaminyl tRNA synthetase (GlnRS, green) in complex with its substrate tRNA^Gln (yellow). Left panel: Color-coded residues depict favorable (blue) and unfavorable (red) effects on the free energy of glutamine binding from mutation at this position. Right panel: Effects of mutation on the ability of GlnRS to catalyze amino acid attachment to the tRNA. In this case all effects are unfavorable.
Credit: Annia Rodriguez/ John Perona / UCSB

A portion of the "code" of life has been unraveled by a UC Santa Barbara graduate student from the town of Jojutla, Mexico. Annia Rodriguez worked with John Perona, professor in UCSB's Department of Chemistry and Biochemistry, to decipher intramolecular communication within a large RNA-protein enzyme responsible for expressing the genetic code for the amino acid glutamine. To their surprise, the experiments by Rodriguez captured a partial glimpse of how the genetic coding of life may have emerged.

Related Articles


The results of the study are published in the journal Structure.

Life is based on the ability of all living cells to convert the genetic information in DNA, into the specific sequences of amino acids that make up the proteins that are the cell's workhorses. The key reaction in this decoding process is the attachment of a particular amino acid to one end of a small RNA molecule known as a transfer RNA. The enzyme that catalyzes this amino acid-RNA attachment is the aminoacyl-tRNA synthetase.

Rodriguez performed many laborious experiments in which she removed portions of the aminoacyl-tRNA synthetase that interact with the anticodon stem of the transfer RNA, far from the part of the enzyme that binds the amino acid. Using a biochemical approach known as rapid chemical quench kinetics, Rodriguez discovered that when she made these changes to the enzyme, the binding of the amino acid to the protein was strengthened, even though the amino acid binds far away from the positions where the changes were made.

"It is totally counterintuitive," said Perona. "Imagine if you had a car, and you took out a gear, and the car went faster. Why would you want that gear if it makes your car go slower?"

In all, Rodriguez found that separately removing seven different "gears" from a distant part of the molecule each caused the amino acid to bind more tightly to the aminoacyl-tRNA synthetase. Perona explained that this provides the first systematic analysis demonstrating long-range communication in an enzyme that depends on RNA for its function.

"So what we think is going on is that these enzyme-RNA interactions far from the amino acid binding site evolved together with the needs of the cell to respond to subtle cues from its environment -- especially in terms of how much amino acid is available," said Perona. "It makes sense in terms of evolution."

Rodriguez is the first in her family to pursue a Ph.D., which she will complete this year. Now 28 years old, she began her career as a nurse in Cuernavaca, Mexico. Then she went on to obtain a B.S. in biochemical engineering at the Instituto Tecnológico de Zacatepec.

Graduation from her undergraduate program called for work at a research institution and she chose UCSB.

Although her current research is not focused specifically on human health, Rodriguez said: "My interest in biochemistry started because I wanted to know the mechanisms by which drugs and medications worked inside the human body. I wanted to learn not just the signs and symptoms of disease, but how diseases are developed in a molecular level."


Story Source:

The above story is based on materials provided by University of California - Santa Barbara. Note: Materials may be edited for content and length.


Journal Reference:

  1. Annia Rodríguez-Hernández, John J. Perona. Heat Maps for Intramolecular Communication in an RNP Enzyme Encoding Glutamine. Structure, 2011; 19 (3): 386 DOI: 10.1016/j.str.2010.12.017

Cite This Page:

University of California - Santa Barbara. "Glimpse of how the 'code' of life may have emerged." ScienceDaily. ScienceDaily, 24 March 2011. <www.sciencedaily.com/releases/2011/03/110323140243.htm>.
University of California - Santa Barbara. (2011, March 24). Glimpse of how the 'code' of life may have emerged. ScienceDaily. Retrieved November 24, 2014 from www.sciencedaily.com/releases/2011/03/110323140243.htm
University of California - Santa Barbara. "Glimpse of how the 'code' of life may have emerged." ScienceDaily. www.sciencedaily.com/releases/2011/03/110323140243.htm (accessed November 24, 2014).

Share This


More From ScienceDaily



More Plants & Animals News

Monday, November 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Ebola-Hit Sierra Leone's Late Cocoa Leaves Bitter Taste

Ebola-Hit Sierra Leone's Late Cocoa Leaves Bitter Taste

AFP (Nov. 23, 2014) — The arable district of Kenema in Sierra Leone -- at the centre of the Ebola outbreak in May -- has been under quarantine for three months as the cocoa harvest comes in. Duration: 01:32 Video provided by AFP
Powered by NewsLook.com
Anglerfish Rarely Seen In Its Habitat Will Haunt You

Anglerfish Rarely Seen In Its Habitat Will Haunt You

Newsy (Nov. 22, 2014) — For the first time Monterey Bay Aquarium recorded a video of the elusive, creepy and rarely seen anglerfish. Video provided by Newsy
Powered by NewsLook.com
Birds Around the World Take Flight

Birds Around the World Take Flight

Reuters - Light News Video Online (Nov. 22, 2014) — An imperial eagle equipped with a camera spreads its wings over London. It's just one of the many birds making headlines in this week's "animal roundup". Jillian Kitchener reports. Video provided by Reuters
Powered by NewsLook.com
Could Your Genes Be The Reason You're Single?

Could Your Genes Be The Reason You're Single?

Newsy (Nov. 21, 2014) — Researchers in Beijing discovered a gene called 5-HTA1, and carriers are reportedly 20 percent more likely to be single. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins