Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


New Thinking on Regulation of Sex Chromosomes in Fruit Flies

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
About the University of Rochester
The University of Rochester ( 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:

More articles from Life Sciences:

nachricht First time-lapse footage of cell activity during limb regeneration
25.10.2016 | eLife

nachricht Phenotype at the push of a button
25.10.2016 | Institut für Pflanzenbiochemie

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Etching Microstructures with Lasers

Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.

This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...

Im Focus: Light-driven atomic rotations excite magnetic waves

Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion

Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

All Focus news of the innovation-report >>>



Event News

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

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Ice shelf vibrations cause unusual waves in Antarctic atmosphere

25.10.2016 | Earth Sciences

Fluorescent holography: Upending the world of biological imaging

25.10.2016 | Power and Electrical Engineering

Etching Microstructures with Lasers

25.10.2016 | Process Engineering

More VideoLinks >>>