Navigation Links
Discovery of jumping gene cluster tangles tree of life
Date:2/4/2011

Since the days of Darwin, the "tree of life" has been the preeminent metaphor for the process of evolution, reflecting the gradual branching and changing of individual species.

The discovery that a large cluster of genes appears to have jumped directly from one species of fungus to another, however, significantly strengthens the argument that a different metaphor, such as a mosaic, may be more appropriate.

"The fungi are telling us something important about evolution something we didn't know," said Antonis Rokas, assistant professor of biological sciences at Vanderbilt. He and research associate Jason Slot reported their discovery in the Jan. 25 issue of the journal Current Biology.

Rokas and Slot discovered that millions of years ago, a cluster of 23 genes jumped from one strain of mold commonly found on starchy foods like bread and potatoes, Aspergillus, to another strain of mold that lives in herbivore dung and specializes in breaking down plant fibers, Podospora.

The findings came as a major surprise, as there are only a handful of cases in recent evolutionary history where this type of gene transfer between organisms, known as horizontal gene transfer, has been reported in complex cells like those found in plants, animals and fungi.

"Because most people didn't believe that such large gene clusters could be transferred horizontally, they haven't looked for them and they haven't been found," Rokas said.

Rokas and Slot detected the unprecedented gene cluster transfer during a detailed comparison of the entire genomes of nearly 100 species of fungi. The primary goal of their research is to identify the most reliable methods for determining the evolutionary relationships of species of all kinds. In the course of their analysis, they discovered the 23-gene capture.

The jumping gene cluster codes for a toxic compound called sterigmatocystin. Cells produce this type of compound to attack competing organisms or to protect themselves from attacks. As a result, these types of compounds are the source of a number of important drugs, like penicillin and cyclosporin, as well as a number of natural poisons.

"Fungi produce an astonishing variety of drugs and poisons. Our discovery that one of the largest gene clusters responsible for making such a poison moved intact between species suggests that horizontal transfers of wholesale pathways may have contributed significantly to the generation of this diversity," Rokas said.

In the past, evolutionary research has focused on the passage of genes from parent to child, known as vertical gene transfer. This process, acted out over the eons of geological time, gives rise to the branching structure of the tree of life.

Since the 1980's, however, evolutionary scientists have become increasingly aware that horizontal or lateral gene transfer also plays a major role in evolution. In vertical gene transfer, all the genetic material in each new species come from a single ancestral species. In horizontal gene transfer, by contrast, species that receive bits of genetic material from its neighbors are directly related to a number of often unrelated species.

Horizontal gene transfer was first discovered in bacteria, and has been recognized as largely responsible for the problem of drug resistance. If one bacterium evolves a method for surviving a drug, this ability can spread rapidly to other unrelated microorganisms via horizontal gene transfer, substantially reducing the drug's effectiveness.

Though researchers now generally agree that horizontal gene transfer is relatively common among simple organisms like bacteria, they have continued to assume that it remained relatively rare among complex organisms like plants and animals.

"The thinking has been that there is very little horizontal gene transfer among plants and animals except for a few big, ancient events and maybe the occasional transfer of a single gene here or there," Slot said. "Our discovery suggests that the horizontal transfer of gene clusters may have been a big player not only in the evolution of bacteria but also in more complex organisms."


'/>"/>

Contact: David F. Salisbury
david.salisbury@vanderbilt.edu
615-343-6803
Vanderbilt University
Source:Eurekalert  

Related biology news :

1. Chemical equator discovery will aid pollution mapping
2. Sirtris review of sirtuin therapeutics for diseases of aging in Nature Reviews Drug Discovery
3. Groundbreaking discovery may lead to stronger antibiotics
4. Discovery of natural compounds that could slow blood vessel growth
5. Nanoscopic screening process to speed drug discovery
6. FSU researchers discovery leads to $1.5 million grant, potential new treatment of liver fibrosis
7. New $11 million center to speed production of new compounds for drug discovery
8. Discovery of giant roaming deep sea protist provides new perspective on animal evolution
9. New discovery may enhance MRI scans, lead to portable MRI machines
10. Kidney function discovery sheds light on genetic complexity of disease
11. Discovery of new gene associated with diabetes risk suggests link with body clock
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Discovery of jumping gene cluster tangles tree of life
(Date:5/16/2016)... --  EyeLock LLC , a market leader of iris-based ... IoT Center of Excellence in Austin, Texas ... embedded iris biometric applications. EyeLock,s iris authentication ... with unmatched biometric accuracy, making it the most proven ... platform uses video technology to deliver a fast and ...
(Date:4/28/2016)... and BANGALORE, India , April 28, ... Systems, a product subsidiary of Infosys (NYSE: INFY ... announced a global partnership that will provide end ... use mobile banking and payment services.      (Logo: ... key innovation area for financial services, but it also plays ...
(Date:4/19/2016)... , UAE, April 20, 2016 ... be implemented as a compact web-based "all-in-one" system solution ... the biometric fingerprint reader or the door interface with ... of modern access control systems. The minimal dimensions of ... ID readers into the building installations offer considerable freedom ...
Breaking Biology News(10 mins):
(Date:6/24/2016)... DIEGO , June 24, 2016 ... more sensitively detects cancers susceptible to PARP inhibitors ... circulating tumor cells (CTCs). The new test has ... HRD-targeted therapeutics in multiple cancer types. ... targeting DNA damage response pathways, including PARP, ATM, ...
(Date:6/23/2016)... CAMBRIDGE, Mass. , June 23, 2016 /PRNewswire/ ... the development of novel compounds designed to target ... compound, napabucasin, has been granted Orphan Drug Designation ... in the treatment of gastric cancer, including gastroesophageal ... cancer stemness inhibitor designed to inhibit cancer stemness ...
(Date:6/23/2016)... Calif. , June 23, 2016  The Prostate Cancer Foundation ... increasingly precise treatments and faster cures for prostate cancer. Members of the Class ... across 15 countries. Read More About the Class of ... ... ...
(Date:6/23/2016)... ... June 23, 2016 , ... In a new case report published today in ... patient who developed lymphedema after being treated for breast cancer benefitted from an injection ... for dealing with this debilitating, frequent side effect of cancer treatment. , ...
Breaking Biology Technology: