One of the surprising discoveries to emerge from the young field of comparative genomics is that drastically different organisms--humans, sea urchins, worms, flies --are endowed with a more or less common set of genes. Given a similar DNA blueprint, then, how do species develop such vast differences in physical shape, size, and complexity?
One insight into this question has also turned out to be surprising. Contrary to the classical "central dogma" of molecular biology, genetic information does not always pass faithfully from genomic DNA to messenger RNA to the synthesis of proteins.
Rather, the information can be significantly altered along the way by a variety of means, including by precision "editing" at the RNA stage to fine-tune the type of proteins that will be produced.
RNA editing was thought to be sparingly used, based on a limited number of studies in mammals and flies. But recently, MBL Whitman Investigator Joshua Rosenthal and colleagues discovered the most prolific usage yet of RNA editing in the common squid, Doryteuthis pealeii, a behaviorally sophisticated marine organism that has long been prized for studies of the nervous system.
By comparing DNA and RNA sequences from the squid brain, the team found that 60 percent of the RNA transcripts had been edited. (A transcript is a stretch of DNA transcribed into an RNA molecule.) This is orders of magnitude more "recoding" of the genetic instructions than has been seen in any other species to date, says Rosenthal, a professor of neurobiology at the Universidad de Puerto Rico.
The 57,000 recoding sites they found in the squid brain (as compared with 100 known recoding sites in humans and 600 in the fruit fly) created tremendous protein diversity, suggesting an important role for RNA editing in the brain physiology of the squid. It may, for example, enable squid to fine-tune its physiological response to environmental variables, such as changes in temperature, a hypothesis that Rosenthal will be exploring this summer at the MBL.
"In squid, RNA editing is so pervasive that the central dogma should be modified to include this process," Rosenthal says. "These results open the possibility that, in many organisms, extensive recoding is a common means of creating functional diversity."
Alon S et al (2015) The majority of transcripts in the squid nervous system are extensively recoded by A-to-I RNA editing. eLife 10.7554/eLife.05198
The Marine Biological Laboratory (MBL) is dedicated to scientific discovery and improving the human condition through research and education in biology, biomedicine, and environmental science. Founded in Woods Hole, Massachusetts, in 1888, the MBL is a private, nonprofit institution and an affiliate of the University of Chicago.
Diana Kenney | EurekAlert!
Water forms 'spine of hydration' around DNA, group finds
26.05.2017 | Cornell University
How herpesviruses win the footrace against the immune system
26.05.2017 | Helmholtz-Zentrum für Infektionsforschung
Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.
Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....
Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.
The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....
An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.
We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...
Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.
Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...
An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...
24.05.2017 | Event News
23.05.2017 | Event News
22.05.2017 | Event News
26.05.2017 | Life Sciences
26.05.2017 | Life Sciences
26.05.2017 | Physics and Astronomy