Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Dartmouth Medical School geneticists discover new role for antisense RNA


Dartmouth Medical School geneticists studying the biological clock have opened yet another window into the role of an unusual form of RNA known as antisense that blocks the messages of protein-encoding genes.

They found that antisense RNA appears to regulate core timing genes in the circadaian clock that drives the 24-hour light-dark cycle of Neurospora, a model organism better known as bread mold.

The results are reported in the February 27 Nature by Drs. Jennifer Loros and Jay C. Dunlap, both DMS professors, and Susan K. Crosthwaite, formerly a postdoctoral fellow at DMS, and Cas Kramer, both of the University of Manchester, England.

Messenger RNA, which has a single-stranded sequence of nucleotides, is called "sense" because it can be decoded to produce a gene product (a protein). Like DNA, this mRNA can form duplexes with a second strand of RNA whose base sequence is complementary to the first strand. The second strand is called the antisense strand because its nucleotide sequence is the complement of "sense" message. When mRNA forms a duplex with a complementary antisense RNA sequence, the message translation is turned off so the sense strand can no longer be decoded to yield a protein product.

As scientists identify more antisense RNAs, they are beginning to realize these might affect a wide variety of processes. The recent findings, write the authors, "provide an unexpected link between antisense RNA and circadian timing."

Studying the development of spores in the bread mold Neurospora, Dunlap and Loros have teased apart the molecular gears that form the basis of most living clocks. Light and dark cycles reset the clocks, they found, the way turning the hands of a clock does. The clock mechanism, a biological oscillator, keeps time through the delicately balanced interplay of the Neurospora clock genes and proteins in a complex of feedback loops.

"We found a long RNA antisense transcript that arises from the frequency gene, known to encode factors important for the operation of the circadian clock in Neurospora," says Dunlap. "The sense transcript encodes proteins that are involved in the feedback loop that is the oscillator in the clock. The antisense transcript runs in the opposite direction, and apparently does not encode a protein, so its actual role is unknown at present. It may simply bock translation, or it may destabilize the sense message. Antisense transcripts are already known, but usually they are quite small, on the order of 20 to 25 bases. This one is quite large, nearly 5,000 bases."

In normal bread mold strains living in the dark, levels of antisense frequency transcripts cycle with respect to the amount of sense frequency transcripts, and they are inducible by light, the researchers determined. However, in strains mutated to abolish induction of antisense frequency RNA by light, the internal clock time was delayed, and resetting of the clock by light was altered.

If similar environmental factors regulate both sense and antisense transcripts, the authors suggest, a role for antisense frequency RNA might be to confer the ability to keep accurate time by limiting the clock response to extremes in the environment. Likewise other antisense RNAs might be involved in maintaining internal stability in other organisms.

DMS Communications | EurekAlert!
Further information:

More articles from Life Sciences:

nachricht Biologists unravel another mystery of what makes DNA go 'loopy'
16.03.2018 | Emory Health Sciences

nachricht Scientists map the portal to the cell's nucleus
16.03.2018 | Rockefeller University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Locomotion control with photopigments

Researchers from Göttingen University discover additional function of opsins

Animal photoreceptors capture light with photopigments. Researchers from the University of Göttingen have now discovered that these photopigments fulfill an...

Im Focus: Surveying the Arctic: Tracking down carbon particles

Researchers embark on aerial campaign over Northeast Greenland

On 15 March, the AWI research aeroplane Polar 5 will depart for Greenland. Concentrating on the furthest northeast region of the island, an international team...

Im Focus: Unique Insights into the Antarctic Ice Shelf System

Data collected on ocean-ice interactions in the little-researched regions of the far south

The world’s second-largest ice shelf was the destination for a Polarstern expedition that ended in Punta Arenas, Chile on 14th March 2018. Oceanographers from...

Im Focus: ILA 2018: Laser alternative to hexavalent chromium coating

At the 2018 ILA Berlin Air Show from April 25–29, the Fraunhofer Institute for Laser Technology ILT is showcasing extreme high-speed Laser Material Deposition (EHLA): A video documents how for metal components that are highly loaded, EHLA has already proved itself as an alternative to hard chrome plating, which is now allowed only under special conditions.

When the EU restricted the use of hexavalent chromium compounds to special applications requiring authorization, the move prompted a rethink in the surface...

Im Focus: Radar for navigation support from autonomous flying drones

At the ILA Berlin, hall 4, booth 202, Fraunhofer FHR will present two radar sensors for navigation support of drones. The sensors are valuable components in the implementation of autonomous flying drones: they function as obstacle detectors to prevent collisions. Radar sensors also operate reliably in restricted visibility, e.g. in foggy or dusty conditions. Due to their ability to measure distances with high precision, the radar sensors can also be used as altimeters when other sources of information such as barometers or GPS are not available or cannot operate optimally.

Drones play an increasingly important role in the area of logistics and services. Well-known logistic companies place great hope in these compact, aerial...

All Focus news of the innovation-report >>>



Industry & Economy
Event News

Ultrafast Wireless and Chip Design at the DATE Conference in Dresden

16.03.2018 | Event News

International Tinnitus Conference of the Tinnitus Research Initiative in Regensburg

13.03.2018 | Event News

International Virtual Reality Conference “IEEE VR 2018” comes to Reutlingen, Germany

08.03.2018 | Event News

Latest News

Wandering greenhouse gas

16.03.2018 | Earth Sciences

'Frequency combs' ID chemicals within the mid-infrared spectral region

16.03.2018 | Physics and Astronomy

Biologists unravel another mystery of what makes DNA go 'loopy'

16.03.2018 | Life Sciences

Science & Research
Overview of more VideoLinks >>>