Navigation Links
Molecular sleuths track evolution through the ribosome

A new study of the ribosome, the cell's protein-building machinery, sheds light on the oldest branches of the evolutionary tree of life and suggests that differences in ribosomal structure between the three main branches of that tree are "molecular fossils" of the early evolution of protein synthesis.

The new analysis, from researchers at the University of Illinois, reveals that key regions of the ribosome differ between bacteria and archaea, microbes that the researchers say are genetically closer to eukarya, the domain of life that includes humans. The study appears this week in the Proceedings of the National Academy of Sciences.

The findings confirm and extend the early work of Illinois microbiology professor Carl Woese, an author on the study. Woese was the first to look for signs of evolution in the ribosome, where genetic information is translated into proteins. In the mid-1970s, he and his colleagues found consistent differences in the sequence of nucleotides that spell out the RNA of the ribosome in bacteria and archaea. These "molecular signatures" were so pronounced that Woese concluded that the archaea comprised a separate domain of life, distinct from bacteria and eukarya (animals, plants, fungi and protists). His classification system is now widely accepted.

"Carl Woese and his colleagues years ago established that protein translation had to be well developed when the evolution of modern cells started," said Illinois chemistry professor Zaida Luthey-Schulten, an author on the new study. "So the evolution of cells and the evolution of translation are really linked to one another."

The ribosome has two subunits, each made up of RNA and proteins. It interacts with a host of other molecules to guide the assembly of new proteins.

The researchers analyzed the sequence of nucleotides (the building blocks of RNA) and amino acids (the building blocks of proteins) that make up the ribosome.

They also looked at the three-dimensional structures of the ribosomal RNA and proteins and their proximity to each other.

Graduate student Elijah Roberts, lead author on the study, developed computer programs to analyze the ribosomal sequences of different organisms. Whenever he found a ribosomal RNA or protein sequence that differed between bacteria and archaea, he screened the database to determine whether a sequence was unique to a given domain.

"To be a molecular signature a sequence has to be common to all members of a single domain of life, but not another," Luthey-Schulten said.

Using the three-dimensional structures available for some bacterial and archaeal ribosomes, the researchers were also able to determine where in the ribosome these molecular signatures occurred.

"Until the 2000s, when these structures became available, you weren't able to correlate where these signatures were with what was touching them in 3-D space," Roberts said. "So nobody had ever done this sort of analysis before."

The researchers found that 50 percent of the signatures distinguishing the archaeal and bacterial ribosomes is located in five percent of the ribosomal RNA sequence. Most of these molecular signatures occur in regions that are critical to ribosomal function.

They also found correlations between some ribosomal protein and RNA signatures, which they say is evidence that the ribosomal RNA and proteins co-evolved.

"The ramifications of this work are it gives you a much better way to probe how this universal machinery changes from one organism to another," Luthey-Schulten said.

"In that the ribosome constitutes the core of the cellular translation mechanism, which is the sine qua non of gene expression, which is the essence of life as we know it, these findings constitute a major step in understanding the evolution of life, which is still a journey of a thousand miles," Woese said.

The new findings also have implications for human health, Luthey-Schulten said. Because the signatures that differentiate bacteria from other organisms often occur in regions that are essential to ribosomal functioning, they will likely be targets for the development of new antibiotic drugs, she said.


Contact: Diana Yates
University of Illinois at Urbana-Champaign

Related biology technology :

1. Center for Molecular Medicine Only Regional Provider of Test Suggested in FDA Alert on Prescribing Codeine to Nursing Mothers
2. Amsterdam Molecular Therapeutics to Release H1 2007 Results on August 29, 2007
3. Amsterdam Molecular Therapeutics Reports Half Year Results 2007
4. Rosetta Genomics to Present at the American Association of Cancer Research (AACR) "Molecular Diagnostics in Cancer Therapeutic Development" Conference
5. Glycominds Joins Biomolecular Photonic (BMP) Consortium to Develop New Molecular Imaging Technique
6. Former Pfizer Director of Inflammation Molecular Sciences to Spearhead Velcura Therapeutics Inflammatory Disease Initiatives
7. Sunesis Pharmaceuticals to Present Data at the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics
8. Astex Drug Candidates to be Featured at the 2007 AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics
9. Center for Molecular Medicine One of the First Midwest Labs to Offer Advanced Test for Patients with Metastatic Breast Cancer
10. Delivering Molecular Imaging Solutions Across Clinical Specialties: Siemens Showcases New Technologies at RSNA 2007
11. Center for Molecular Medicine Offers Xceed Ziplex(TM) Services to Research Community
Post Your Comments:
Related Image:
Molecular sleuths track evolution through the ribosome
(Date:11/30/2015)... ... November 30, 2015 , ... Imagine Exhibitions ... World: The Exhibition, opening in March 2016 at Melbourne Museum in Melbourne, Australia. ... including several North American tour dates. The Exhibition is based on Universal Pictures’ ...
(Date:11/30/2015)... 2015  Champions Oncology, Inc. (CSBR), engaged in the ... the development and use of oncology drugs, today announced ... be presenting at the LD MICRO Investor Conference on ... (PST).  The conference, held at the Luxe Sunset Bel ... , will feature 200 small/micro-cap companies and is expected ...
(Date:11/30/2015)... 2015 Human Longevity, Inc. (HLI), the genomics-based, ... Cypher Genomics, Inc., a leading genome informatics company offering ... solutions. The San Diego -based company ... CEO and Co-founder, Ashley Van Zeeland , Ph.D., who ... details of the deal were not disclosed. ...
(Date:11/30/2015)... -- TapImmune, Inc. (TPIV), a clinical-stage ... and gene-based immunotherapeutics and vaccines for the treatment of ... presenting at the 8 th Annual LD Micro ... PT. Dr. John N. Bonfiglio a TapImmune ... presentation and will join TapImmune management in meeting with ...
Breaking Biology Technology:
(Date:11/30/2015)... DEERFIELD BEACH, Fla. , Nov. 30, 2015 ... selected as a finalist in this year,s Fierce Innovation ... publisher of FierceHealthIT , ... BIOCLAIM was recognized as a finalist in the ... --> ...
(Date:11/26/2015)... DUBLIN , Nov. 26, 2015 Research ... of the "Capacitive Fingerprint Sensors - Technology and ... --> --> ... market, especially in smartphones. The fingerprint sensor vendor Idex ... fingerprint sensor units in mobile devices and of the ...
(Date:11/20/2015)... NXTD ) ("NXT-ID" or the ... mobile commerce market and creator of the Wocket® smart ... recently interviewed on The RedChip Money Report ... on Bloomberg Europe , Bloomberg Asia, Bloomberg Australia, ... NXTD ) ("NXT-ID" or the "Company"), a biometric authentication ...
Breaking Biology News(10 mins):