Navigation Links
Elephant shark genome provides new insights into bone formation and adaptive immunity in humans

1. Singapore, Jan, 09, 2014 - Scientists at A*STAR's Institute of Molecular and Cell Biology (IMCB) led an international team of researchers that sequenced and analysed the genome of the elephant shark. A comparison of the elephant shark genome with human and other vertebrate genomes revealed why the skeleton of sharks consists entirely of cartilage instead of bones. The findings carry potential implications for human bone disease treatment. The analysis also sheds new light on the origin of the adaptive immune system. The findings of this study are published in the 9 January, 2014 issue of the prestigious scientific journal, Nature.

2. The collaboration with 12 international institutions was headed by IMCB's Prof Byrappa Venkatesh, who is also a chairperson of the "Genome10K" Project. The project was largely funded by the National Institutes of Health (NIH), USA, the world's foremost centre for the support of biomedical research.

Analysis of the elephant shark genome

3. Elephant shark is a member of cartilaginous fishes, which are the oldest living group of jawed vertebrates that diverged from bony vertebrates about 450 million years ago. Cartilaginous fishes include sharks, rays, skates and chimaeras. Unlike humans and other bony vertebrates, cartilaginous fishes are unable to replace cartilage with bone. Among over 1,200 species of cartilaginous fishes, the elephant shark was sequenced due to its compact genome size. Analysis of the elephant shark genome identified a family of genes absent in elephant shark but present in all bony vertebrates. A significant reduction in bone formation was observed when a member of this gene family was knocked out in zebrafish, thereby indicating the importance of this gene family in bone formation. The finding has important implications towards our understanding of bone-related diseases such as osteoporosis and hence the development of effective therapeutic strategies for them.

4. An unexpected finding was that elephant shark appears to lack special types of immune cells previously considered essential for defence against viral/bacterial infections and preventing autoimmune reactions such as diabetes and rheumatoid arthritis . Despite this seemingly primitive organization of the immune system, sharks exhibit robust immune defences and are long-lived. By challenging long-held notions, this discovery has opened up a new avenue towards the development of non-intuitive strategies to shape the immune functions of humans.

5. The study also found that the elephant shark genome is the slowest evolving among all vertebrates, including the coelacanth, popularly known as a "living fossil", whose genes were recently shown to be evolving slower than those of other bony vertebrates . Furthermore, large blocks of elephant shark and human chromosomes were found to be highly similar. The markedly slow evolution of the elephant shark genome and its similarity to the human genome, further underscores its importance as a reference genome for comparative genomic studies aimed at better understanding of the human genome.

6. Prof Byrappa Venkatesh, Research Director at IMCB, and lead author of the Nature paper added, "The slow evolving genome of the elephant shark is probably the best proxy for the ancestor of all jawed-vertebrates that became extinct a long time ago. It is a cornerstone for improving our understanding of the development and physiology of human and other vertebrates as illustrated by our analysis of the skeletal system and immune system genes."

7. Dr Wes Warren, senior author of the Nature paper commented, "Although cartilaginous vertebrates and bony vertebrates diverged about 450 million years ago, with the elephant shark genome in hand, we can now begin to identify key genetic adaptations in the evolutionary tree."

8. Prof Hong Wanjin, Executive Director of IMCB, said, "Over the years, IMCB has carried out several remarkable genomic projects and we are excited to showcase yet another milestone. Not only has our research team sequenced the first shark-family member genome, they have also uncovered many insights significant to the field of genomic and medical research through the genome analysis."

9. Prof Sir David Lane, Chief Scientist at A*STAR, said, "We are delighted that a Singapore laboratory conceived and led a major international genome project. The international research grant from NIH, USA is a testimony of Singapore's world-class standard in genomics research."


Contact: Tan Yun Yun
Agency for Science, Technology and Research (A*STAR), Singapore

Related biology news :

1. MU researchers study of African forest elephants helps guide research efforts in the US
2. Researchers unmask centuries-old elephant imposter
3. Crop-raiding elephants flee tiger growls
4. Study documents decimation of critically endangered forest elephant
5. Elephants are vanishing from DRCs best-run reserve
6. 11,000 elephants slaughtered in national park
7. Low rainfall and extreme temperatures double risk of baby elephant deaths
8. Relocating elephants fails to decrease human-wildlife conflict
9. Violence in Mali threatening survival of endangered elephants
10. Conservationists to create blueprint for saving Malaysias elephants
11. Southern elephant seals likely detect prey bioluminescence for foraging
Post Your Comments:
(Date:10/29/2015)... Va. , Oct. 29, 2015 Daon, ... today that it has released a new version of ... customers in North America have ... IdentityX v4.0 also includes a FIDO UAF certified ... are already preparing to activate FIDO features. These customers ...
(Date:10/29/2015)... Oct. 29, 2015  Connected health pioneer, Joseph ... explosion of technology-enabled health and wellness, and the business ... The Internet of Healthy Things . ... smartphones even existed, Dr. Kvedar, vice president, Connected Health, ... care delivery, moving care from the hospital or doctor,s ...
(Date:10/29/2015)... 29, 2015 Today, LifeBEAM , ... with 2XU, a global leader in technical performance ... hat with advanced bio-sensing technology. The hat will ... monitor key biometrics to improve overall training performance. ... two companies will bring together the most advanced technology, ...
Breaking Biology News(10 mins):
(Date:11/24/2015)... ... November 24, 2015 , ... International Society ... one of the premier annual events for pharmaceutical manufacturing: 2015 Annual Meeting. The ... where ISPE hosted the largest number of attendees in more than a decade. ...
(Date:11/24/2015)... India , November 24, 2015 ... a new market research report "Oligonucleotide Synthesis Market by ... Application (PCR, Gene Synthesis, Diagnostic, DNA, RNAi), End-User (Research, ... 2020", published by MarketsandMarkets, the market is expected to ... Million in 2015, at a CAGR of 10.1% during ...
(Date:11/24/2015)... November 24, 2015 SHPG ) announced today ... the Piper Jaffray 27 th Annual Healthcare Conference in ... 2015, at 8:30 a.m. EST (1:30 p.m. GMT). --> ... Officer, will participate in the Piper Jaffray 27 th Annual ... on Tuesday, December 1, 2015, at 8:30 a.m. EST (1:30 p.m. ...
(Date:11/24/2015)... QUEBEC CITY , Nov. 24, 2015 /PRNewswire/ ... (the "Company") announced today that the remaining 11,000 ... Common Share Purchase Warrants (the "Series B Warrants") ... agreement were exercised on November 23, 2015, which ... Common Shares.  After giving effect to the issuance ...
Breaking Biology Technology: