Navigation Links
From the heart: How cells divide to form different but related muscle groups

Using the model organism Ciona intestinalis, commonly known as the sea squirt, researchers at the University of California, Berkeley, have uncovered the origins of the second heart field in vertebrates.

Sea squirts are bag-like gelatinous creatures whose full genome has been sequenced--one that shares 80 percent of its genes with humans. Though its body is clearly more primitive than creatures with backbones and spinal columns, the sea squirt nevertheless offers a valuable resource to scientists seeking to understand the evolutionary links between these simple chordates and more complex creatures.

Vertebrate hearts form from two distinct cell populations, termed first heart field and second heart field. From these fields are derived, respectively, the left ventricle and the right ventricle and outflow tract of the heart. The lineage relationship between these cell types was uncertain but mysteriously, a number of reports linked cells in the second heart field to muscle cells in the lower jaw in birds and mammals.

"The heart-jaw connection is evolutionarily ancient," said developmental biologist Mike Levine."We think the sea squirt is valuable as a developmental model to study these connections because it is a simple chordate that is the closest living relative of vertebrates, including humans."

By tracking the movement of specific cells during embryonic development, Levine and his team found that heart progenitor cells also produce the atrial siphon muscles (ASMs--responsible for expelling water during feeding) in Ciona. Researchers think it is possible that the atrial siphon in the sea squirt is the equivalent of the lower jaw in vertebrates. During development, the ASM precursor cells in Ciona express the same markers seen in cells that form the jaw muscles and second heart field in vertebrates, evidence that supports the idea that these muscle groups are linked. These results also suggest that "re-routing" of jaw cells into the developing heart could lead to evolution of the more intricate hearts seen in higher vertebrates such as humans.

"This is an exciting discovery, because we still don't know the rules for evolving novelty," Levine explained. "We understand how you lose things via evolution, but we really don't understand how you make something more complex."


Contact: Lisa Van Pay
National Science Foundation

Related biology news :

1. Preventing a broken heart: Research aims to reduce scarring from heart attacks
2. Just published: Doctor of the Heart: My Life in Medicine, by Isadore Rosenfeld, M.D.
3. The embryonic heart: Imaging life as it happens
4. Jefferson scientists deliver toxic genes to effectively kill pancreatic cancer cells
5. NSF funds new Center for the Physics of Living Cells at Illinois
6. When cells go bad
7. The role of stem cells in renewing the cornea
8. Breast cancer cells recycle to escape death by hormonal therapy
9. Models of eel cells suggest electrifying possibilities
10. Scientists identify a molecule that coordinates the movement of cells
11. Form of Crohns disease traced to disabled gut cells
Post Your Comments:
(Date:6/14/2017)... 15, 2017  IBM (NYSE: IBM ) is introducing several ... dedicated to developing collaboration between startups and global businesses, taking ... During the event, nine startups will showcase the solutions they ... industries. France is ... with a 30 percent increase in the number of startups ...
(Date:4/24/2017)... , April 24, 2017 ... and partner with  Identity Strategy Partners, LLP (IdSP) ... "With or without President Trump,s March 6, 2017 ... Terrorist Entry , refugee vetting can be instilled with ... resettlement. (Right now, all refugee applications are suspended ...
(Date:4/13/2017)... PUNE, India , April 13, 2017 According ... Identity Proofing, Identity Authentication, Identity Analytics, Identity Administration, and Authorization), Service, Authentication ... by MarketsandMarkets™, the IAM Market is expected to grow from USD 14.30 ... Annual Growth Rate (CAGR) of 17.3%. ... ...
Breaking Biology News(10 mins):
(Date:10/10/2017)... ... October 10, 2017 , ... For the ... won a US2020 STEM Mentoring Award. Representatives of the FirstHand program travelled to ... Experience from US2020. , US2020’s mission is to change the trajectory of STEM ...
(Date:10/10/2017)... ... October 10, 2017 , ... The Pittcon Program Committee ... honoring scientists who have made outstanding contributions to analytical chemistry and applied ... the world’s leading conference and exposition for laboratory science, which will be held ...
(Date:10/9/2017)... ... October 09, 2017 , ... ... 2017, in the medical journal, Epilepsia, Brain Sentinel’s SPEAC® System which uses ... EEG, in detecting generalized tonic-clonic seizures (GTCS) using surface electromyography (sEMG). The ...
(Date:10/6/2017)... ... October 06, 2017 , ... ... discussion and webinar on INSIGhT, the first-ever adaptive clinical trial for glioblastoma (GBM). ... Institute. The event is free and open to the public, but registration is ...
Breaking Biology Technology: