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 A Map of the Cell’s Power Station
18.08.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau

nachricht On the way to developing a new active ingredient against chronic infections
18.08.2017 | Deutsches Zentrum für Infektionsforschung

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

A Map of the Cell’s Power Station

18.08.2017 | Life Sciences

Engineering team images tiny quasicrystals as they form

18.08.2017 | Physics and Astronomy

Researchers printed graphene-like materials with inkjet

18.08.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>