Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Keeping traffic moving

23.05.2011
An enzyme helps control the extension of cellular tendrils by regulating the delivery of supplies needed for growth

The body of the adult fruit fly is covered with hair-like bristles (Fig. 1) that act as sensory organs for detecting tactile stimuli. Each one consists of a single cell that has gradually elongated over the course of pupal development, reinforced by bundles of actin protein filaments.


Figure 1: An electron microscope image of a sensory bristle from the body of the fruit fly Drosophila melanogaster. Copyright : 2011 Tetsuhisa Otani

The signaling protein IKKå helps to regulate this process by controlling the organization of these actin bundles, but a recent study from Shigeo Hayashi and colleagues at the RIKEN Center for Development Biology in Kobe has revealed that IKKå also promotes bristle growth by managing the trafficking of cellular cargoes (1).

Initial experiments by Hayashi and team showed that activated IKKå is primarily found at the tips of developing bristles, where growth-associated cargoes are most likely to be unloaded. “Membranes and associated proteins are water-insoluble and thus do not easily diffuse to distant sites, and one model is that distal trafficking actively delivers such insoluble materials as packages,” explains Hayashi.

Membrane-enclosed bubbles known as endosomes are a core component in this process, using so-called motor proteins to travel along routes defined by a microscopic ‘railway’ of fibers known as microtubules. The researchers found that this trafficking is severely disrupted in the absence of IKKå, with endosomes remaining trapped at the ends of the bristle rather than being distributed throughout the cell.

Hayashi and colleagues determined that IKKå interacts with a protein called Nuf, which links the motor protein Dynein with a key endosome-associated protein and thus contributes to directional transport of cargoes toward the tip of the growing bristle. Upon arrival at the tip, IKKå-mediated inactivation of Nuf sends the newly emptied endosomes on a return trip, thereby completing a ‘recycling’ process. “Such endosomal movement occurs in other cell types, but the shape of bristles makes this shuttling very prominent,” says Hayashi. “I think this is a very good example of how a highly specialized cell and its shape can reveal a mechanism of general significance.”

Many other cells grow in a similar fashion, ranging from the tiny branches that help connect neurons to the hairs on plant roots that assist in water absorption, and Hayashi speculates that similar regulatory mechanisms may also operate in these contexts. Moving forward, he and his colleagues will further explore the apparently central coordinating role of IKKå. “We are currently studying actin as a target,” says Hayashi, “and we are also studying upstream regulators of IKKå, hoping to uncover a comprehensive view of this signaling pathway.”

The corresponding author for this highlight is based at the Laboratory for Morphogenetic Signaling, RIKEN Center for Developmental Biology

Journal information

(1) Otani, T., Oshima, K., Onishi, S., Takeda, M., Shinmyozu, K., Yonemura, S. & Hayashi, S. IKKå regulates cell elongation through recycling endosome shuttling. Developmental Cell 20, 219–232 (2011).

gro-pr | Research asia research news
Further information:
http://www.riken.jp
http://www.researchsea.com

Further reports about: RIKEN cell type motor protein sensory organ synthetic biology

More articles from Life Sciences:

nachricht How brains surrender to sleep
23.06.2017 | IMP - Forschungsinstitut für Molekulare Pathologie GmbH

nachricht A new technique isolates neuronal activity during memory consolidation
22.06.2017 | Spanish National Research Council (CSIC)

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Quantum thermometer or optical refrigerator?

23.06.2017 | Physics and Astronomy

A 100-year-old physics problem has been solved at EPFL

23.06.2017 | Physics and Astronomy

Equipping form with function

23.06.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>