Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

A diaphanous control during embryo formation

09.04.2008
Gabinete de Planeamento, Estratégia, Avaliação e Relações Internacionais / Ministério da Ciência, Tecnologia e Ensino Superior

A gene called Diaphanous (or Dia) has just been uncovered as a major regulator during embryo formation. The research now published in the journal Development shows how Dia mutations in fruit flies embryos result in a serious of defects during morphogenesis (process by which cells differentiate into tissues and structures), including loss of adhesion, abnormal movements and even migration of cells from one tissue to another.

The discovery contributes to a better understanding of how tissue and organ formation is regulated and, consequently, to, one day, be able to intervene therapeutically. Furthermore, the loss of adhesion and abnormal mobility that occurs when Dia is mutated is very similar to what happens during cancer metastases formation, suggesting that this gene might also have a role in cancer.

During morphogenesis the cells change shape and migrate to new positions in order to achieve the right body plan. The cytoskeleton and the adherent junctions are two major structures involved in these processes: while the first is the cell internal scaffolding - a dynamic structure that helps maintaining the cell shape while also mediating its movements - adherent junctions are connections between cell membranes and cytoskeleton elements that maintain adjacent cells together. During morphogenesis, both structures are tightly coordinated in order to achieve the right balance between stability within the tissue and capability to respond to the environmental through shape and motility variations, but exactly how this occurs and which genes/proteins are involved is still far from being understood.

Diaphanous-related formins (DRF) are a class of regulators known to affect events during morphogenesis although their exact mechanism of action has remained unclear due to several experimental problems. In fact, not only most species have more than one DRF with overlapping functions creating difficulties when trying to find “which one does what”, but also DRF mutations tend to kill the mutated cells making experiments unfeasible.

But in the research now published Catarina Homem, a Portuguese PHD student, and supervisor Mark Peifer at the University of North Carolina at Chapel Hill, USA manage to overcome these problems by working in fruit flies (Drosophila) – which have just one DRF – Dia – and by using a temperature-sensitive Dia mutation , which allowed the researchers to reduce the gene expression only after the cells were fully formed – so not compromising their viability - but before their destiny in the tissues was decided. Together with this mutant Homem and Peifer also used Drosophilas with a Dia constitutive mutation – so where the gene is activated all the time instead of the normal on-off switch in accordance with necessity – as well as offspring obtained from crossing the different mutant Drosophila.

By analysing and comparing embryonic tissue formation in the various fruit flies Homem and Peifer were able to discover that Dia stabilises adherent junctions and controls cell movements during morphogenesis, and that this was mediated by affecting the quantity and activation levels of two major proteins involved in cytoskeleton movement and cell-cell adhesion - actin and myosin. Actin and myosin are better known for their role generating muscles’ contractions but actin – which is an integrant part of the cytoskeleton – also reacts with myosin to create the cell membrane tensions that allow the cell to move. Dia mutations were shown to result in several morphogenic defects, including loss of cell adhesion, abnormal motility and even invasion of neighboring tissues.

In conclusion, Homem and Peifer ‘s work reveals Dia as a major regulator molecule for cell adhesion and cytoskeleton function, acting directly on actin and myosin to regulate cell shape, adhesion and movement. Their study is particularly interesting because it uses several mutations and tests them in a variety of tissues creating a full image of Dia’s role in morphogenesis.

Also interesting is the observation that Dia mutations can transform adherent immobile cells into mobile invasive cell that spread into other tissues, a process known to occur when cancer metastases are formed and when cells from the original tumour gain abnormal mobility and migrate spreading the disease to remote locations. It will be interesting now to investigate if it is in fact possible to associate Dia mutations with cancer, something that Peifer’s laboratory – with a strong interest in cancer research – will no doubt do soon.

Catarina Amorim | alfa
Further information:
http://www.ncbi.nlm.nih.gov/pubmed/18256194?dopt=Abstract

Further reports about: DRF Dia Embryo Homem Mutation Myosin Peifer adherent adhesion cytoskeleton formation morphogenesis

More articles from Life Sciences:

nachricht First-of-its-kind chemical oscillator offers new level of molecular control
15.12.2017 | University of Texas at Austin

nachricht New technique could make captured carbon more valuable
15.12.2017 | DOE/Idaho National Laboratory

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: First-of-its-kind chemical oscillator offers new level of molecular control

DNA molecules that follow specific instructions could offer more precise molecular control of synthetic chemical systems, a discovery that opens the door for engineers to create molecular machines with new and complex behaviors.

Researchers have created chemical amplifiers and a chemical oscillator using a systematic method that has the potential to embed sophisticated circuit...

Im Focus: Long-lived storage of a photonic qubit for worldwide teleportation

MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.

Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...

Im Focus: Electromagnetic water cloak eliminates drag and wake

Detailed calculations show water cloaks are feasible with today's technology

Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

New technique could make captured carbon more valuable

15.12.2017 | Life Sciences

First-of-its-kind chemical oscillator offers new level of molecular control

15.12.2017 | Life Sciences

A chip for environmental and health monitoring

15.12.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>