PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

First shark genome decoded

Genome of the elephant shark provides new insights into immunity and bone formation

2014-01-09
(Press-News.org) Contact information: Dr. Thomas Boehm
boehm@immunbio.mpg.de
49-761-510-8329
Max-Planck-Gesellschaft
First shark genome decoded Genome of the elephant shark provides new insights into immunity and bone formation

This news release is available in German.

An international team of researchers, including scientists of the Max Planck Institute of Immunobiology and Epigenetics, has sequenced and analyzed the genome of the elephant shark. Comparison of the elephant shark genome with human and other vertebrate genomes has revealed why the skeleton of sharks is made up largely of cartilage and not bone like the human skeleton and that the immune system of the shark is much simpler than that of humans. The findings of Byrappa Venkatesh and his coworkers are published in the latest issue of the scientific journal, Nature.

An unexpected finding of the immune system analysis was that sharks appear to lack special types of so-called T-helper lymphocytes, that – until now – were considered to be essential for defence against viral/bacterial infections and preventing autoimmune reactions such as diabetes and rheumatoid arthritis in vertebrates.

Despite this seemingly primitive organization of the immune system, sharks exhibit robust immune defences and are long-lived. "The structure of the immune system of the elephant shark is very different from mammals," said Thomas Boehm, co-author and director at the Max Planck Institute of Immunobiology and Epigenetics in Freiburg, Germany. "It is obvious that sharks can efficiently deal with all kinds of infections without this particular cell type. This indicates that nature can come up with different solutions to the same problem," stated Boehm.

What happens when T-helper cells are being destroyed can be observed in AIDS patients, who succumb to viral and bacterial infections. Up to now, it was assumed that cells are essential for an immune system. The new results are challenging this long-held notion and open up an unprecedented avenue towards the development of non-intuitive strategies to modulate the immune functions of humans.

The researchers also investigated why cartilaginous fishes, including the elephant shark, are unable to replace cartilage with bone like humans and other bony vertebrates. Genome analysis was able to highlight a family of genes that are absent in sharks but present in all bony vertebrates and are critical for bone formation. When the researchers inactivated these genes in bony fishes such as the zebrafish, calcification did not occur. This finding is a strong indication that the investigated gene family could be a starting point for a better understanding of bone diseases such as osteoporosis.

In addition, the study revealed that the elephant shark genome is the slowest evolving among all vertebrates. The elephant shark even beats the coelacanth, also called "the living fossil", that has recently been shown to evolve extremely slowly. Therefore, the elephant shark is probably the best proxy for the ancestor of all jawed-vertebrates that became extinct a long time ago.

Cartilaginous fishes (comprising sharks, rays, skates and chimaeras) are the oldest living group of jawed-vertebrates that diverged from bony vertebrates about 450 million years ago. The elephant shark (Callorhinchus milii) is a chimaera that inhabits temperate waters of the continental shelves off southern Australia and New Zealand, at depths of 200 to 500 meters. From approximately 1,000 species of cartilaginous fishes, elephant shark was chosen as a model because of its relatively compact genome which is one third the size of the human genome.



INFORMATION:

The elephant shark genome project was funded mainly by the National Institutes of Health (NIH), USA. It is a collaborative effort of scientists from 12 international institutions, including the Max Planck Institute of Immunobiology and Epigenetics (MPI-IE) in Freiburg, Germany. Viruses, bacteria and other parasites are a continuous threat to all living beings. Therefore, most of them possess elaborate defence strategies to combat these unwanted intruders. At the Max Planck Institute of Immunobiology and Epigenetics, Thomas Boehm studies the evolution of the immune system and its development and function during lifetime of animals. For his fundamental work on development, differentiation and evolution of immune systems, Thomas Boehm is awarded the prestigious Ernst Jung Award for Medicine 2014.

Original publication

Venkatesh B et al. (2014)
Elephant shark genome provides unique insights into gnathostome evolution
Nature, January 8, 2014. doi:10.1038/nature12826



ELSE PRESS RELEASES FROM THIS DATE:

Bio-inspired glue keeps hearts securely sealed

2014-01-09
Bio-inspired glue keeps hearts securely sealed Adhesive may improve how surgeons treat congenital heart defects and other heart problems Boston, MA – When a child is born with a heart defect such as a hole in the heart, the highly invasive therapies are ...

Coral chemical warfare: Suppressing a competitor enhances susceptibility to a predator

2014-01-09
Coral chemical warfare: Suppressing a competitor enhances susceptibility to a predator Competition may have a high cost for at least one species of tropical seaweed. Researchers examining the chemical warfare taking place on Fijian coral reefs have found that ...

Infants show ability to tell friends from foes

2014-01-09
Infants show ability to tell friends from foes Infant cognition study offers new evidence that babies make inferences about social relationships around them Even before babies have language skills or much information about social structures, they can infer whether ...

Stem cell research identifies new gene targets in patients with Alzheimer's disease

2014-01-09
Stem cell research identifies new gene targets in patients with Alzheimer's disease Scientists provide new insight into cause of Alzheimer's disease NEW YORK, NY (January 8, 2014) – Scientists at The New York Stem Cell Foundation (NYSCF) Research Institute in ...

Engineers make world's fastest organic transistor, herald new generation of see-through electronics

2014-01-09
Engineers make world's fastest organic transistor, herald new generation of see-through electronics Teams from Stanford and the University of Nebraska-Lincoln collaborate to make thin, transparent semiconductors that could become the foundation for cheap, high-performance ...

GPS traffic maps for leatherback turtles show hotspots to prevent accidental fishing deaths

2014-01-09
GPS traffic maps for leatherback turtles show hotspots to prevent accidental fishing deaths PHILADELPHIA (Jan. 8, 2014)- The leatherback turtle in the Pacific Ocean is one of the most endangered animals in the world. Its population has declined by more than 90 percent since ...

Mental disorders in mid-life and older adulthood more prevalent than previously reported

2014-01-09
Mental disorders in mid-life and older adulthood more prevalent than previously reported Common methods of assessing mental or physical disorders may consistently underestimate the prevalence of mental disorders among middle-aged ...

Study discovers natural hybridization produced dolphin species

2014-01-09
Study discovers natural hybridization produced dolphin species First documented natural hybrid species among marine mammals A newly published study on the clymene dolphin, a small and sleek marine mammal living in the Atlantic Ocean, shows that this species arose ...

Nociceptin: Nature's balm for the stressed brain

2014-01-09
Nociceptin: Nature's balm for the stressed brain LA JOLLA, CA - January 8, 2014 - Collaborating scientists at The Scripps Research Institute (TSRI), the National Institutes of Health (NIH) and the University of Camerino in Italy have published new findings on a system ...

New device can reduce sleep apnea episodes by 70 percent, Pitt-UPMC study shows

2014-01-09
New device can reduce sleep apnea episodes by 70 percent, Pitt-UPMC study shows VIDEO: Ryan Soose, M.D., director of the UPMC Division ...

LAST 30 PRESS RELEASES:

Pink skies

Monkeys are world’s best yodellers - new research

Key differences between visual- and memory-led Alzheimer’s discovered

% weight loss targets in obesity management – is this the wrong objective?

An app can change how you see yourself at work

NYC speed cameras take six months to change driver behavior, effects vary by neighborhood, new study reveals

New research shows that propaganda is on the rise in China

Even the richest Americans face shorter lifespans than their European counterparts, study finds

Novel genes linked to rare childhood diarrhea

New computer model reveals how Bronze Age Scandinavians could have crossed the sea

Novel point-of-care technology delivers accurate HIV results in minutes

Researchers reveal key brain differences to explain why Ritalin helps improve focus in some more than others

Study finds nearly five-fold increase in hospitalizations for common cause of stroke

Study reveals how alcohol abuse damages cognition

Medicinal cannabis is linked to long-term benefits in health-related quality of life

Microplastics detected in cat placentas and fetuses during early pregnancy

Ancient amphibians as big as alligators died in mass mortality event in Triassic Wyoming

Scientists uncover the first clear evidence of air sacs in the fossilized bones of alvarezsaurian dinosaurs: the "hollow bones" which help modern day birds to fly

Alcohol makes male flies sexy

TB patients globally often incur "catastrophic costs" of up to $11,329 USD, despite many countries offering free treatment, with predominant drivers of cost being hospitalization and loss of income

Study links teen girls’ screen time to sleep disruptions and depression

Scientists unveil starfish-inspired wearable tech for heart monitoring

Footprints reveal prehistoric Scottish lagoons were stomping grounds for giant Jurassic dinosaurs

AI effectively predicts dementia risk in American Indian/Alaska Native elders

First guideline on newborn screening for cystic fibrosis calls for changes in practice to improve outcomes

Existing international law can help secure peace and security in outer space, study shows

Pinning down the process of West Nile virus transmission

UTA-backed research tackles health challenges across ages

In pancreatic cancer, a race against time

Targeting FGFR2 may prevent or delay some KRAS-mutated pancreatic cancers

[Press-News.org] First shark genome decoded
Genome of the elephant shark provides new insights into immunity and bone formation