Navigation Links
Changing environment organizes genetic structure
Date:11/13/2007

HOUSTON -- Nov. 13, 2007 -- What is the fundamental creative force behind life on Earth" It's a question that has vexed mankind for millennia, and thanks to theory and almost a year's worth of number-crunching on a supercomputer, Rice University physicist and bioengineer Michael Deem thinks he has the answer: A changing environment may organize the structure of genetic information itself.

Deem's research is available online and slated to appear next month in Physical Review Letters.

"Our results suggest that the beautiful, intricate and interrelated structures observed in nature may be the generic result of evolution in a changing environment," Deem said. "The existence of such structure need not necessarily rest on intelligent design or the anthropic principle."

The information that allows all living things to survive and reproduce is encoded in genes. Deem's theory probed the structure of this genetic information, looking for patterns that were created over time.

The study by Deem and postdoctoral fellow Jun Sun found the structure of genetic information becomes increasingly modular when two conditions are taken as givens: horizontal gene transfer (HGT) and a changing environment. Like modular furniture that can be rearranged in different functional patterns, modular genes are standardized components that lend themselves to flexible rearrangement, and this genetic modularity arises spontaneously because of the selective pressure of a changing environment and the existence of horizontal gene transfer.

Genes are typically transferred vertically. People, plants and animals pass genes vertically, from generation to generation, through sexual reproduction. Bacteria transfer genes vertically via conjugation. HGT allows genes, pieces of genes and collections of genes to move between species, even in cases where vertical transfer is physically impossible.

Though scientists have known about HGT for years, it was thought to be rare and infrequent until sophisticated tools opened the genetic history of many species in the 1990s. Today, HGT is widely accepted as the primary reason for antibiotic drug resistance, and Deem said HGT played a significant role in human development as well. "Our acquired immune system is a product of horizontal gene transfer and is organized in a modular fashion," he said.

Deem's study found that an organism's fitness -- the likelihood that it and its descendants will survive in a rapidly changing environment -- increases as the modularity of its genetic code increases. Another finding was that the faster the environment changes, the more modular genetic information becomes.

Because modularity begets complexity, the more modular genetic information becomes, the more complex the web of life becomes. For example, human beings are far more complex than singled-celled yeast, yet they have only about four times as many genes. The complex nature of multicellular plants and animals derives not only from the genes themselves, but also from the complex regulatory networks that control the production and interaction of the products of genes -- proteins -- to fulfill multiple roles. This regulatory network is another example of modular organization.

"Modularity and hierarchy are prevalent in biology, from the way atoms are arranged in molecules, molecules into amino acids and amino acids into secondary structures, domains and proteins," Deem said. "This hierarchy continues with multiprotein complexes, protein regulation pathways, cells, organs, individuals, species and ecosystems. Our research suggests that modularity and hierarchy are prevalent because genetic information self-organizes into increasingly more modular forms. A changing environment and the biochemistry of horizontal gene transfer appear to be part of the source for this fundamental creativity of life."


'/>"/>

Contact: Jade Boyd
jadeboyd@rice.edu
713-348-6778
Rice University
Source:Eurekalert

Related biology news :

1. Changing the global dietary environment
2. Global deal fuels QUTs world-changing research
3. New study examines how rearing environment can alter navigation
4. SRMs track fire retardants in humans and environment
5. Study finds environmental tests help predict hospital-acquired Legionnaires disease risk
6. Genes, Environment and Health Initiative invests in genetic studies, environmental monitoring
7. UCR engineers to develop new tool to measure how environmental exposures affect health
8. TAU scientists probe deep questions aboard EcoOceans environmental research ship
9. Genes and environment grant funds close look at nature-nurture overlap in common diseases
10. Americans remain pessimistic about the environment, Stanford-AP survey finds
11. Environmental setting of human migrations in the circum-Pacific Region
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/9/2016)... innovation leader in attendance control systems is proud to announce the introduction of fingerprint ... sure the right employees are actually signing in, and to even control the opening ... ... ... Photo ...
(Date:6/3/2016)... June 3, 2016 ... Nepal hat ein ... hochsicherer geprägter Kennzeichen, einschließlich Personalisierung, Registrierung und ... der Produktion und Implementierung von Identitätsmanagementlösungen. Zahlreiche ... im Januar teilgenommen, aber Decatur wurde als ...
(Date:6/2/2016)... 2016 Perimeter Surveillance & Detection ... Physical Infrastructure, Support & Other Service  The ... offers comprehensive analysis of the global Border Security ... revenues of $17.98 billion in 2016. Now: ... leader in software and hardware technologies for advanced video ...
Breaking Biology News(10 mins):
(Date:6/23/2016)... TORONTO , June 23, 2016 /PRNewswire/ - ... Ontario biotechnology company, Propellon ... the development and commercialization of a portfolio of ... cancers. Epigenetic targets such as WDR5 represent an ... contribute significantly in precision medicine for cancer patients. ...
(Date:6/23/2016)... -- The Biodesign Challenge (BDC), a university competition that asks ... systems and biotechnology, announced its winning teams at the ... York City . The teams, chosen ... MoMA,s Celeste Bartos Theater during the daylong summit. Keynote ... of architecture and design, and Suzanne Lee , ...
(Date:6/23/2016)... LOUISVILLE, Ky. , June 23, 2016 /PRNewswire/ ... from two Phase 1 clinical trials of its ... double-blind, placebo-controlled, single and multiple ascending dose studies ... and pharmacodynamics (PD) of subcutaneous injection in healthy ... APL-2 subcutaneously (SC) either as a single dose ...
(Date:6/23/2016)... ... June 23, 2016 , ... ... and technical consulting, provides a free webinar on Performing Quality Investigations: ... 2016 at 12pm CT at no charge. , Incomplete investigations are still a ...
Breaking Biology Technology: