Navigation Links
Invasion of genomic parasites triggered modern mammalian pregnancy

Genetic parasites invaded the mammalian genome more than 100 million years ago and dramatically changed the way mammals reproduce -- transforming the uterus in the ancestors of humans and other mammals from the production of eggs to a nurturing home for developing young, a new Yale University study has found.

The findings published online Sept. 25 in the journal Nature Genetics describe in unprecedented detail the molecular changes that allowed mammals to carry their developing young within the safety of the womb rather than laying them in nests or carrying them around in pouches.

"In the last two decades there have been dramatic changes in our understanding of how evolution works," said Gunter Wagner, the Alison Richard Professor of Ecology and Evolutionary Biology (EEB) and senior author of the paper. "We used to believe that changes only took place through small mutations in our DNA that accumulated over time. But in this case we found a huge cut-and-paste operation that altered wide areas of the genome to create large-scale morphological change."

The Yale team studying the evolutionary history of pregnancy looked at cells found in the uterus associated with placental development. They compared the genetic make-up of these cells in opossums marsupials that give birth two weeks after conception to armadillos and humans, distantly related mammals with highly developed placentas that nurture developing fetuses for nine months.

They found more than 1500 genes that were expressed in the uterus solely in the placental mammals. Intriguingly, note the researchers, the expression of these genes in the uterus is coordinated by transposons essentially selfish pieces of genetic material that replicate within the host genome and used to be called junk DNA.

"Transposons grow like parasites that have invaded the body, multiplying and taking up space in the genome," said Vincent J. Lynch, research scientist in EEB and lead author of the paper.

But they also activate or repress genes related to pregnancy, he said.

"These transposons are not genes that underwent small changes over long periods of time and eventually grew into their new role during pregnancy," Lynch said. "They are more like prefabricated regulatory units that install themselves into a host genome, which then recycles them to carry out entirely new functions like facilitating maternal-fetal communication" Lynch said.


Contact: Bill Hathaway
Yale University

Related biology news :

1. UH Manoa researchers release results of statewide survey of snail, slug invasions in Hawaii
2. Invasions by alien plants have been mapped in European Union
3. New method for detection of phosphoproteins reveals regulator of melanoma invasion
4. Master gene SRC-3 enables breast cancer growth, invasion
5. Scientists discover ancient viral invasion that shaped human genome
6. UC Riverside entomologist helps manage invasion threats posed to Californias avocados
7. Defective cell surface glue is key to tumor invasion
8. Tree resin the key evidence of current and historic insect invasions
9. Manage biological invasions like natural disasters, biologists say
10. High-throughput screen finds compounds that regulate cancer cell invasion
11. Open minded and open access: NeoBiota, a new publishing platform for invasion biologists
Post Your Comments:
(Date:11/12/2015)... 12, 2015  Arxspan has entered into an ... Harvard for use of its ArxLab cloud-based suite ... The partnership will support the institute,s efforts to ... research information internally and with external collaborators. The ... managing the Institute,s electronic laboratory notebook, compound and ...
(Date:11/9/2015)... DUBLIN , Nov. 09, 2015 /PRNewswire/ ... announced the addition of the "Global ... to their offering. --> ... "Global Law Enforcement Biometrics Market 2015-2019" ... Research and Markets ( ) ...
(Date:10/29/2015)... LA JOLLA, Calif. , Oct. 29, 2015 /PRNewswire-USNewswire/ ... released a new report titled, "DNA Synthesis and Biosecurity: ... how well the Department of Health and Human Services ... was issued in 2010. --> ... advances, but it also has the potential to pose ...
Breaking Biology News(10 mins):
(Date:11/25/2015)... , November 25, 2015 2 nouvelles ... fois les différences entre les souches bactériennes retrouvées ... des êtres humains . Ces recherches  ouvrent ... envisager la prise en charge efficace de l,un ... chez les chats .    --> 2 ...
(Date:11/25/2015)... 2015  Neurocrine Biosciences, Inc. (Nasdaq: NBIX ) ... CEO of Neurocrine Biosciences, will be presenting at the ... New York . .   ... 5 minutes prior to the presentation to download or ... will be available on the website approximately one hour ...
(Date:11/25/2015)... Nov. 25, 2015 Orexigen® Therapeutics, Inc. (Nasdaq: ... in a fireside chat discussion at the Piper Jaffray ... . The discussion is scheduled for Wednesday, December ... .  A replay will be available for 14 ... , Julie NormartVP, Corporate Communications and Business Development ...
(Date:11/24/2015)... 24, 2015  Asia-Pacific (APAC) holds the third-largest ... market. The trend of outsourcing to low-cost locations ... higher volume share for the region in the ... margins in the CRO industry will improve. ... ( ), finds that the market earned ...
Breaking Biology Technology: