Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Ancient genetic program employed in more than just fins and limbs

19.11.2014

Hox genes provide blueprint for a diversity of body plan features, SF State researchers find

Hox genes are master body-building genes that specify where an animal's head, tail and everything in between should go. There's even a special Hox gene program that directs the development of limbs and fins, including specific modifications such as the thumb in mice and humans. Now, San Francisco State University researchers show that this fin- and limb-building genetic program is also utilized during the development of other vertebrate features.

The discovery means this ancient genetic program is employed in a variety of features beyond fins and limbs. For instance, this Hox program helps to pattern the barbels in paddlefish -- sensory organs near the fish's mouth. In addition, the limb-building program had previously been observed in a cluster of genes called the HoxD genes.

But SF State Associate Professor of Biology Karen Crow and her colleagues demonstrated for the first time that the program also operates in the HoxA cluster of genes during the development of the vent, a structure in all ray-finned fishes that is similar to a urethra, indicating that the regulation of this expression pattern is older and more widely utilized than thought.

Together, these new findings "really expand our view of this Hox limb-building program," said Crow. "Now we think it could be associated with all kinds of features that arise in different species."

"There is tremendous interest in animal diversity and how novel features arise in evolution," she added, "and we're just beginning to understand the genetic basis of morphological diversity."

Hox genes are the master regulatory genes that specify the identity and position of body parts during an animal's development. Hox genes are expressed at different times and places in the developing embryo, and that pattern of expression "acts like a code that sets up an address system for body parts," Crow explained.

One kind of Hox expression pattern establishes the "address" for the head-to-tail locations of body parts. But a reversal of this pattern, for some Hox genes, creates a code that specifies body parts that extend out away from the body, like fins, limbs, or now even barbels or vents. Evolutionary biologists have been intensely interested in this limb-building program, because it is part of the genetic basis of how fins evolved to become limbs, and how specialized structures arose in human evolution, such as the genetic code that specifies the thumb should be different from the other digits.

Researchers know that this limb-building program has operated at least since the origin of jawed vertebrates, some 440-480 million years ago. "So we wondered if this Hox repertoire is being utilized in all kinds of other features that people haven't yet looked at," said Crow.

Since discovering this particular Hox program in barbels and vents, Crow's lab has found the program operating in the development of claspers in skates and rays. They are now looking to see if the program helps direct the patterning of other appendages, like the manta ray's distinctively curled head fins called cephalic lobes, or the brood structures where seahorses and pipefish carry their young.

"I think this genetic program is deployed in all kinds of vertebrate features that have yet to be discovered," Crow said. "We're just beginning to understand the underlying genetic basis of different structures in different animals. And, surprisingly, some aspects of those genetic instructions are shared."

"HoxA and HoxD expression in a variety of vertebrate body plan features reveals an ancient origin for the distal Hox program" by Crow, Sophie Archambeault and Julia Ann Taylor was published online Nov. 19 in the journal EvoDevo. The study was supported by grants from the National Science Foundation.

SF State is the only master's-level public university serving the counties of San Francisco, San Mateo and Marin. The University enrolls nearly 30,000 students each year and offers nationally acclaimed programs in a range of fields -- from creative writing, cinema, biology and history to broadcast and electronic communication arts, theatre arts and ethnic studies. The University's more than 228,000 graduates have contributed to the economic, cultural and civic fabric of San Francisco and beyond.

Jonathan Morales | EurekAlert!
Further information:
http://www.sfsu.edu/

More articles from Life Sciences:

nachricht Warming ponds could accelerate climate change
21.02.2017 | University of Exeter

nachricht An alternative to opioids? Compound from marine snail is potent pain reliever
21.02.2017 | University of Utah

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Impacts of mass coral die-off on Indian Ocean reefs revealed

21.02.2017 | Earth Sciences

Novel breast tomosynthesis technique reduces screening recall rate

21.02.2017 | Medical Engineering

Use your Voice – and Smart Homes will “LISTEN”

21.02.2017 | Trade Fair News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>