Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

IU-led study reveals new insights into light color sensing and transfer of genetic traits

06.05.2016

Analysis of a globally abundant marine phytoplankton sheds light on horizontal gene transfer

An international team led by Indiana University researchers has uncovered the regulation of a system that allows a globally abundant bacterium to efficiently capture sunlight and perform photosynthesis.


The marine cyanobacterium Synechococcus is tested for its response to various light colors by IU, Japanese and French scientists in the Okazaki Large Spectrograph at the National Institute for Basic Biology in Okazaki, Japan. Laterally projected regions of the light spectrum are reflected downward by mirrors positioned above the beakers containing the cells being tested.

Credit: David Kehoe

The study -- led by IU biologist David M. Kehoe and conducted by Joseph E. Sanfilippo, IU Ph.D. student, and Animesh Shukla, former IU Ph.D. student, in collaboration with researchers in the United States and France -- is the first to show how a process that improves light capture in marine cyanobacteria is regulated.

The research also provides insight into how genes can be easily transferred between cells in the marine environment by a process called horizontal gene transfer. This is a common form of DNA movement involving genomic regions called "genome islands" that is important for the evolution of many organisms.

The research is reported in the Proceedings of the National Academy of Sciences.

The cyanobacterium Synechococcus is the second most common photosynthetic bacterium in the Earth's oceans. The IU study focused on how Synechococcus controls its ability to efficiently capture both blue and green light for photosynthesis.

"It's important for us to understand more about marine cyanobacteria because they're a significant part of the base of the Earth's food chain," said Kehoe, professor in the IU Bloomington College of Arts and Sciences' Department of Biology. "Our planet essentially runs on power from the sun, and these organisms are important for converting sunlight into the organic compounds that are food for other species. We could not exist without these and other 'primary producers' because we can't create food from sunlight."

In the marine environment, blue and green light penetrates the water column to different depths. In shallow coastal waters, many Synechococcus cells efficiently use green light for photosynthesis, while in deeper ocean waters, the bacteria maximize their capture and use of blue light. About one quarter of all marine Synechococcus examined so far can carry out this process, called "chromatic acclimation."

Kehoe led an earlier study that provided the first mechanistic insights into this "chameleon-like" ability of many Synechococcus to capture blue and green light.

The current study involved four groups of French and American scientists.

"Our colleagues in France, who are excellent biological oceanographers, were intrigued by the molecular aspects of chromatic acclimation, while the American groups were intrigued by its ecological implications," said Kehoe, a molecular biologist. "We recognized that by combining our efforts, we could examine this process at many scales, from the molecular to the ecological. It's a truly collaborative, multidisciplinary project."

The French group -- led by Frédéric Partensky and Laurence Garczarek of the Pierre and Marie Curie University in Paris and CNRS Station Biologique in Roscoff, France -- uncovered a genome island with six genes that correlated with the ability to undergo chromatic acclimation. Professor Wendy Schluchter and Ph.D. student Adam A. Nguyen at the University of New Orleans provided biochemical analyses for the study. Jonathan A. Karty, associate scientist in the IU Bloomington Department of Chemistry, contributed mass spectrometry results that were critical for the group's discoveries.

Together, the group's results indicate that a small genome island confers the ability to undergo chromatic acclimation. If a particular strain of Synechococcus does not have the genome island, it cannot undergo chromatic acclimation. However, if a strain acquires the genome island, as one quarter of strains appear to have done, it will likely undergo chromatic acclimation.

The group discovered that two genes, named fciA and fciB, located on the genome island are required to turn on and off the expression of the other genes on the genome island. As a result, this genome island appears to be self-regulating and able to tune its own response to changes in surrounding light color environment.

The results of this study provide important insight into regulation of horizontally transferred genes. Although the regulation must be correct when such genes enter a new organism, regulatory genes are often not located near the genes they regulate in a genome.

"We found that this genome island includes both types of genes, making it self-contained by allowing the proper regulation of this process to be provided along with the capacity for chromatic acclimation. We predict that this facilitates its spread in the environment," Kehoe said.

###

IU facilities used in the study were the Indiana Molecular Biology Institute, IU Center for Genomics and Bioinformatics, and the METACyt Biochemical Analysis Center and Mass Spectrometry Facility in the IU Department of Chemistry.

This research was funded in part by the National Institutes of Health, the National Science Foundation and the IU Bloomington Office of the Vice Provost for Research's Bridge Funding Program.

Media Contact

Kevin Fryling
kfryling@iu.edu
812-856-2988

 @IndianaResearch

http://newsinfo.iu.edu 

Kevin Fryling | EurekAlert!

More articles from Life Sciences:

nachricht Multi-institutional collaboration uncovers how molecular machines assemble
02.12.2016 | Salk Institute

nachricht Fertilized egg cells trigger and monitor loss of sperm’s epigenetic memory
02.12.2016 | IMBA - Institut für Molekulare Biotechnologie der Österreichischen Akademie der Wissenschaften GmbH

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

Im Focus: Fraunhofer ISE Develops Highly Compact, High Frequency DC/DC Converter for Aviation

The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.

Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

UTSA study describes new minimally invasive device to treat cancer and other illnesses

02.12.2016 | Medical Engineering

Plasma-zapping process could yield trans fat-free soybean oil product

02.12.2016 | Agricultural and Forestry Science

What do Netflix, Google and planetary systems have in common?

02.12.2016 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>