Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New Thinking on Regulation of Sex Chromosomes in Fruit Flies

20.09.2011
Research Disputes Established Theory on Chromosome Activity

Fruit flies have been indispensible to our understanding of genetics and biological processes in all animals, including humans. Yet, despite being one of the most studied of animals, scientists are still finding the fruit fly to be capable of surprises, as evidenced by new research at the University of Rochester.

The latest revelation has to do with the activity of the X chromosome in male fruit flies. It was widely accepted that all X chromosomes in male fruit flies showed an increased level of activity. It was also believed that, in the absence of increased activity, the cell would die. But biologists at the University got some unexpected results when they studied chromosomal behavior in fruit flies.

The findings, by the lab of Associate Professor Daven Presgraves, have been published in the journal PLoS Biology.

While chromosomes in most animals come in pairs, that is not the case with all sex chromosomes. Males, typically being the ones to determine the gender of offspring, carry both the X and Y chromosomes, compared to the female, which carries two X chromosomes. Since the sex chromosomes carry genetic instructions for traits that go beyond gender determination, a process—called dosage compensation—evolved to ensure that the X chromosomes in males and females are expressed at the same level.

Dosage compensation occurs differently from one species to the next. In male fruit flies (Drosophila), the expression—or activity—of genes on most of the single X chromosomes is doubled to match the expression of the two X chromosomes in female cells. Scientists have believed that the process of dosage compensation occurs in all cells of the male fruit fly. But University biologists have discovered that is not the case with the germ (reproductive) cells in the testes.

A complex of proteins called the dosage compensation complex is responsible for upregulating gene expression in somatic (non-reproductive) cells. "That complex doesn't exist in germ cells, so it was assumed that dosage compensation occurred in those cells by some other mechanism," said lead author Colin Meiklejohn, "We showed there is no upregulation of X chromosomes in the testes of flies."

Scientists have assumed that dosage compensation is needed for any male cell to survive, said Meiklejohn. It's not clear why there are no negative effects in the male sex cells, but Meiklejohn said that's a question University researchers will look at next.

Contact: Peter Iglinski
peter.iglinski@rochester.edu
585.273.4726
About the University of Rochester
The University of Rochester (www.rochester.edu) is one of the nation's leading private universities. Located in Rochester, N.Y., the University gives students exceptional opportunities for interdisciplinary study and close collaboration with faculty through its unique cluster-based curriculum. Its College, School of Arts and Sciences, and Hajim School of Engineering and Applied Sciences are complemented by its Eastman School of Music, Simon School of Business, Warner School of Education, Laboratory for Laser Energetics, School of Medicine and Dentistry, School of Nursing, Eastman Institute for Oral Health, and the Memorial Art Gallery.

Peter Iglinski | EurekAlert!
Further information:
http://www.rochester.edu

More articles from Life Sciences:

nachricht Nanoparticle Exposure Can Awaken Dormant Viruses in the Lungs
16.01.2017 | Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt

nachricht Cholera bacteria infect more effectively with a simple twist of shape
13.01.2017 | Princeton 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: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

Im Focus: How to inflate a hardened concrete shell with a weight of 80 t

At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).

Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...

Im Focus: Bacterial Pac Man molecule snaps at sugar

Many pathogens use certain sugar compounds from their host to help conceal themselves against the immune system. Scientists at the University of Bonn have now, in cooperation with researchers at the University of York in the United Kingdom, analyzed the dynamics of a bacterial molecule that is involved in this process. They demonstrate that the protein grabs onto the sugar molecule with a Pac Man-like chewing motion and holds it until it can be used. Their results could help design therapeutics that could make the protein poorer at grabbing and holding and hence compromise the pathogen in the host. The study has now been published in “Biophysical Journal”.

The cells of the mouth, nose and intestinal mucosa produce large quantities of a chemical called sialic acid. Many bacteria possess a special transport system...

Im Focus: Newly proposed reference datasets improve weather satellite data quality

UMD, NOAA collaboration demonstrates suitability of in-orbit datasets for weather satellite calibration

"Traffic and weather, together on the hour!" blasts your local radio station, while your smartphone knows the weather halfway across the world. A network of...

Im Focus: Repairing defects in fiber-reinforced plastics more efficiently

Fiber-reinforced plastics (FRP) are frequently used in the aeronautic and automobile industry. However, the repair of workpieces made of these composite materials is often less profitable than exchanging the part. In order to increase the lifetime of FRP parts and to make them more eco-efficient, the Laser Zentrum Hannover e.V. (LZH) and the Apodius GmbH want to combine a new measuring device for fiber layer orientation with an innovative laser-based repair process.

Defects in FRP pieces may be production or operation-related. Whether or not repair is cost-effective depends on the geometry of the defective area, the tools...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

Nothing will happen without batteries making it happen!

05.01.2017 | Event News

 
Latest News

Multiregional brain on a chip

16.01.2017 | Power and Electrical Engineering

New technology enables 5-D imaging in live animals, humans

16.01.2017 | Information Technology

Researchers develop environmentally friendly soy air filter

16.01.2017 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>