Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

The skeleton: Size matters

29.10.2009
Consortia of European scientists show new role for master patterning genes in defining number of vertebrae in spine

Vertebrates have in common a skeleton made of segments, the vertebrae. During development of the embryo, each segment is added in a time dependent manner, from the head-end to the tail-end: the first segments to be added become the vertebrae of the neck, later segments become the vertebrae with ribs and the last ones the vertebra located in the tail (in the case of a mouse, for example).

In this process, it is crucial that, on the one hand, each segment, as it matures, becomes the correct type of vertebra and, on the other, that the number of vertebrae in the skeleton, and therefore the size of the spine, are minutely controlled.

It has long been known that the identity of each vertebra is due to the activation of a class of genes called Hox. Now, in the latest issue of Developmental Cell (*) researchers from the Instituto Gulbenkian de Ciência, in Portugal, the Institute KNAW and University Medical Centre (The Netherlands) show that besides determining the identity of the vertebrae, Hox genes also have a say in how many are going to be formed at all.

... more about:
»Cdx genes »Hox »Hox gene »cell death »mouse embryo

There is a huge diversity in number of vertebrae in animals: some have many vertebrae, and are thus longer, like a snake, and others have fewer vertebrae and are shorter, like mice. Vertebrae are made from precursors known as somites, formed in the embryos, sequentially from head to tail. This process is directly linked to growth of the embryo at its tail end: the more it grows, the more somites it makes and, as a result the more vertebrae the adult animal has. Of the many genes involved in this growth, a family of genes called Cdx are known to play a central role.

According to Moises Mallo, group leader at the IGC and one of the lead authors on the paper, 'We knew that some Hox genes are not activated when the Cdx genes are turned off, but this was always considered to be part of a mechanism to ensure that each new somite generates the appropriate type of vertebra. We now show that the activation of Hox genes is also part of how Cdx genes promote growth of the embryo at its tail end: when the relevant Hox genes were activated in the Cdx mouse mutants the embryos recovered and were born with a quite normal vertebral column, proving that the Hox genes were able to compensate for the lack of Cdx. This is a novel role for Hox genes'.

The researchers also show that some Hox genes are important to stop the addition of extra segments, at later stages in development. Indeed, if Hox genes that are usually active later on in development, in the last forming segments, are turned on before their time, in mouse embryos, they interrupt addition of new segments and lead to a tail truncation in the vertebral column.

As Mallo puts it, 'This paper provides and important addition to a long-standing view on the role of the Hox genes – one of the most-studied genes involved in embryonic development: that it controls not only identity, but also number of vertebrae. Although these observations were made in the tail-end region of the embryo, it is very likely that similar mechanisms might be acting to determine the number of segments closer to the head".

(*)Young et al., Cdx and Hox Genes Differentially Regulate Posterior Axial Growth in Mammalian Embryos, Developmental Cell (2009), doi:10.1016/j.devcel.2009.08.010

Silvia Castro | EurekAlert!
Further information:
http://www.gulbenkian.pt

Further reports about: Cdx genes Hox Hox gene cell death mouse embryo

More articles from Life Sciences:

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

nachricht CWRU researchers find a chemical solution to shrink digital data storage
22.06.2017 | Case Western Reserve University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

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)...

Im Focus: Optoelectronic Inline Measurement – Accurate to the Nanometer

Germany counts high-precision manufacturing processes among its advantages as a location. It’s not just the aerospace and automotive industries that require almost waste-free, high-precision manufacturing to provide an efficient way of testing the shape and orientation tolerances of products. Since current inline measurement technology not yet provides the required accuracy, the Fraunhofer Institute for Laser Technology ILT is collaborating with four renowned industry partners in the INSPIRE project to develop inline sensors with a new accuracy class. Funded by the German Federal Ministry of Education and Research (BMBF), the project is scheduled to run until the end of 2019.

New Manufacturing Technologies for New Products

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

A new technique isolates neuronal activity during memory consolidation

22.06.2017 | Life Sciences

Plant inspiration could lead to flexible electronics

22.06.2017 | Materials Sciences

A rhodium-based catalyst for making organosilicon using less precious metal

22.06.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>