Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

When ’reaper’ gene comes, cell death follows

18.05.2004


’Reaper’ genes essential for cell death



In what may be the cellular equivalent of watching the Grim Reaper in action, University of Utah School of Medicine researchers have shown that two "death activator" genes are essential for cell death when Drosophila (fruit flies) metamorphose from larvae to adults. Death of obsolete larval tissue is critical in insect metamorphosis.

The two genes--reaper (rpr) and hid (head involution defective)--act by overcoming the protective efforts of a death inhibitor, DIAP1. Once DIAP1 is disabled, the inexorable begins and larval tissues like the salivary glands are rapidly destroyed, according to Carl S. Thummel, Ph.D., professor of human genetics at the Eccles Institute of Human Genetics, and doctoral student Viravuth P. Yin. The two will publish their findings in the May 25 print edition of the Proceedings of the National Academy of Sciences. The article will appear online the week of May 17.


"They are true (cell) death genes in Drosophila that are critical for the destruction of larval tissue during metamorphosis," Thummel said.

The finding opens the possibility that someday death-inducing genes could be unloosed to specifically kill unwanted cells--such as tumors.

Cell death (apoptosis) begins when ecdysone, a steroid hormone, binds to its receptor, EcR/USP. This binding allows the receptor to activate three key regulatory genes--E93, BR-C, and E74A. Those genes turn on reaper and hid, which then deactivate the death inhibitor DIAP1. When DIAP1 is no longer functioning, cell death is unleashed in the salivary glands, leading to the destruction of larval tissue and their replacement by adult structures.

Ecdysone already was known to regulate a number of genes; and reaper and hid were known as death activators. But it had not been proved that those two genes are essential for salivary gland cell death to occur, and no roles were known for DIAP1 in preventing premature larval cell death. Ecdysone is the critical signal in starting the process, according to Thummel.

"This hormone (ecdysone) is the trigger that changes Drosophila from its larval to adult form," he said.

To identify roles for reaper and hid in cell death, Yin and Thummel used a combination of genetic tools to reduce their function. This allowed them to determine how the two genes influenced cell death in Drosophila larvae. When hid was removed from the process, salivary gland death was partially blocked. Both reaper and hid had to be inactivated before Yin saw a complete block in cell death, leading to the conclusion that both genes are required for efficient larval tissue cell death.


For information contact:
Carl Thummel, Ph.D., 581-2937 or Viravuth P. Yin, 581-2612.

Cindy Fazzi | EurekAlert!
Further information:
http://www.uuhsc.utah.edu/

More articles from Life Sciences:

nachricht Sensory Perception Is Not a One-Way Street
17.10.2018 | Eberhard Karls Universität Tübingen

nachricht Sex or food? Decision-making in single-cell organisms
17.10.2018 | Max-Planck-Institut für chemische Ökologie

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Goodbye, silicon? On the way to new electronic materials with metal-organic networks

Scientists at the Max Planck Institute for Polymer Research (MPI-P) in Mainz (Germany) together with scientists from Dresden, Leipzig, Sofia (Bulgaria) and Madrid (Spain) have now developed and characterized a novel, metal-organic material which displays electrical properties mimicking those of highly crystalline silicon. The material which can easily be fabricated at room temperature could serve as a replacement for expensive conventional inorganic materials used in optoelectronics.

Silicon, a so called semiconductor, is currently widely employed for the development of components such as solar cells, LEDs or computer chips. High purity...

Im Focus: Storage & Transport of highly volatile Gases made safer & cheaper by the use of “Kinetic Trapping"

Augsburg chemists present a new technology for compressing, storing and transporting highly volatile gases in porous frameworks/New prospects for gas-powered vehicles

Storage of highly volatile gases has always been a major technological challenge, not least for use in the automotive sector, for, for example, methane or...

Im Focus: Disrupting crystalline order to restore superfluidity

When we put water in a freezer, water molecules crystallize and form ice. This change from one phase of matter to another is called a phase transition. While this transition, and countless others that occur in nature, typically takes place at the same fixed conditions, such as the freezing point, one can ask how it can be influenced in a controlled way.

We are all familiar with such control of the freezing transition, as it is an essential ingredient in the art of making a sorbet or a slushy. To make a cold...

Im Focus: Micro energy harvesters for the Internet of Things

Fraunhofer IWS Dresden scientists print electronic layers with polymer ink

Thin organic layers provide machines and equipment with new functions. They enable, for example, tiny energy recuperators. In future, these will be installed...

Im Focus: Dynamik einzelner Proteine

Neue Messmethode erlaubt es Forschenden, die Bewegung von Molekülen lange und genau zu verfolgen

Das Zusammenspiel aus Struktur und Dynamik bestimmt die Funktion von Proteinen, den molekularen Werkzeugen der Zelle. Durch Fortschritte in der...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Conference to pave the way for new therapies

17.10.2018 | Event News

Berlin5GWeek: Private industrial networks and temporary 5G connectivity islands

16.10.2018 | Event News

5th International Conference on Cellular Materials (CellMAT), Scientific Programme online

02.10.2018 | Event News

 
Latest News

Robot-assisted sensor system for quality assurance of press-hardened components

17.10.2018 | Trade Fair News

Sensory Perception Is Not a One-Way Street

17.10.2018 | Life Sciences

Plant Hormone Makes Space Farming a Possibility

17.10.2018 | Agricultural and Forestry Science

VideoLinks
Science & Research
Overview of more VideoLinks >>>