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:10/29/2015)... 2015 Today, LifeBEAM , a ... 2XU, a global leader in technical performance sports ... with advanced bio-sensing technology. The hat will allow ... key biometrics to improve overall training performance. As ... will bring together the most advanced technology, extensive ...
(Date:10/26/2015)... , October 26, 2015 ... --> adds Biometrics Market ... 2021 as well as Emerging Biometrics ... reports to its collection of IT ... . --> ...
(Date:10/23/2015)... GOLETA, California , October 23, 2015 ... and SensoMotoric Instruments (SMI) announce a mobile plug and ... captured during interactive real-world tasks SensoMotoric Instruments ... of their established wearable solutions for eye tracking and ... behavior captured with SMI Eye Tracking Glasses 2w ...
Breaking Biology News(10 mins):
(Date:11/24/2015)... LEXINGTON, Massachusetts , November 24, 2015 ... 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. ... Poulton , Chief Financial Officer, will participate in the Piper Jaffray ... City , NY on Tuesday, December 1, 2015, at 8:30 ...
(Date:11/24/2015)... AVIV, Israel , Nov. 24, 2015  Tikcro Technologies Ltd. (OTCQB: ... held on December 29, 2015 at 11:00 a.m. Israel ... Co., Electra Tower, 98 Yigal Allon Street, 36 th Floor, ... election of Eric Paneth and Izhak Tamir to ... and Rami Skaliter as external directors; , approval of an amendment ...
(Date:11/24/2015)... Nov. 24, 2015  Twist Bioscience, a company ... Leproust, Ph.D., Twist Bioscience chief executive officer, will ... on December 1, 2015 at 3:10 p.m. Eastern ... City. --> --> ... Twist Bioscience is on Twitter. Sign up to ...
(Date:11/24/2015)... Schlieren, Switzerland (PRWEB) , ... November 24, 2015 , ... ... more organotypic 3D cell culture models, has promoted Melanie Aregger to serve as Chief ... Manager, Ms. Aregger served on the management team and was promoted to ...
Breaking Biology Technology: