Navigation Links
How red blood cells nuke their nuclei
Date:2/10/2008

CAMBRIDGE, Mass. (February 10, 2008) Unlike the rest of the cells in your body, your red blood cells lack nuclei. That quirk dates back to the time when mammals began to evolve. Other vertebrates such as fish, reptiles, and birds, have red cells that contain nuclei that are inactive. Losing the nucleus enables the red blood cell to contain more oxygen-carrying hemoglobin, thus enabling more oxygen to be transported in the blood and boosting our metabolism.

Scientists have struggled to understand the mechanism by which maturing red blood cells eject their nuclei. Now, researchers in the lab of Whitehead Member Harvey Lodish have modeled the complete process in vitro in mice, reporting their findings in Nature Cell Biology online on February 10, 2008. The first mechanistic study of how a red blood cell loses its nucleus, the research sheds light on one of the most essential steps in mammalian evolution.

It was known that as a mammalian red blood cell nears maturity, a ring of actin filaments contracts and pinches off a segment of the cell that contains the nucleus, a type of cell division. The nucleus is then swallowed by macrophages (one of the immune systems quick-response troops). The genes and signaling pathways that drive the pinching-off process, however, were a mystery.

Using a cell-culture system we were actually able to watch the cells divide, go through hemoglobin synthesis and then lose their nuclei, says Lodish, who is also a professor of biology at Massachusetts Institute of Technology. We discovered that the proteins Rac 1, Rac 2 and mDia2 are involved in building the ring of actin filaments.

We were very interested in that Rac 1 and Rac 2 were involved in disposing the nuclei of red blood cells, says Peng Ji, lead author and postdoctoral researcher in the Lodish lab. These proteins are known for their role in creating actin fibers in many body cells, and a necessary component of many important cellular functions including cell division that support cell growth.

His cell-culture system began with red blood cell precursors drawn from an embryonic mouse liver (in mammalian embryos, the liver is the main producer of such cells, rather than bone marrow as in adults). The cultured cells, synchronized to develop together, divided four or five times before losing their nuclei and becoming immature red blood cells. The researchers used simple fluorescence-based assays that enabled them to probe the changes in the red blood cells through the different stages leading up to the loss of the nucleus.

The researchers plan to further investigate the entire process of red blood cell formation, which may lead to insights about genetic alterations that underlie certain red blood cell disorders.

During normal cell division, each daughter cell receives half the DNA, comments Lodish. In this case, when the red blood cell divides, one daughter cell gets all the DNA. Whats fascinating is that in this case, that daughter cell gets eaten by macrophages. Until now, scientists were unable to study these cells because they were unable to see them.


'/>"/>

Contact: Cristin Carr
carr@wi.mit.edu
617-324-0460
Whitehead Institute for Biomedical Research
Source:Eurekalert

Related medicine news :

1. Specific antagonism lowers blood pressure
2. Restricting Blood Flow May Help Heart Bypass Patients
3. FDA Updates Prescription Guidelines for Blood Thinner
4. Doctors Often Miss High Blood Pressure in Kids
5. Back to School Means Return of School Blood Drives
6. Blood-flow detector software show promise in preventing brain damage
7. FDA Approves New Roche West Nile Virus Blood Screening Test
8. Australian-led international study shows blood pressure drugs cut death rate in type 2 diabetes
9. Laser blasts viruses in blood
10. Study Demonstrates Marteks Algal DHA Oil Improves Blood Triglyceride Lipid Levels
11. LifeMasters Provides Tips for Maintaining a Healthy Blood Cholesterol Level
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/25/2016)... ... ... Conventional wisdom preaches the benefits of moderation, whether it’s a matter of ... too high can result in disappointment, perhaps even self-loathing. However, those who set the ... Research from PsychTests.com reveals that behind the tendency to set low expectations ...
(Date:6/24/2016)... ... , ... Marcy was in a crisis. Her son James, eight, was out of control. Prone ... physically. , “When something upset him, he couldn’t control his emotions,” remembers Marcy. “If ... at my other children and say he was going to kill them. If we ...
(Date:6/24/2016)... ... June 24, 2016 , ... Comfort Keepers® of San Diego, CA is ... Road To Recovery® program to drive cancer patients to and from their cancer treatments. ... the highest quality of life and ongoing independence. Getting to and from medical ...
(Date:6/24/2016)... ... June 24, 2016 , ... The Haute Beauty ... Barry M. Weintraub as a prominent plastic surgeon and the network’s newest partner. ... and the most handsome men, look naturally attractive. Plastic surgery should be invisible.” ...
(Date:6/24/2016)... ... June 24, 2016 , ... Venture Construction Group (VCG) ... held on June 20th at the Woodmont Country Club at 1201 Rockville Pike, Rockville, ... dedicated to helping service members that have been wounded in battle and their families. ...
Breaking Medicine News(10 mins):
(Date:6/23/2016)... , June 23, 2016 Research and ... Global Market - Forecast to 2022" report to their ... treatment method for the patients with kidney failure, it replaces ... fluid from the patient,s blood and thus the treatment helps ... and chloride in balance. Increasing number of ...
(Date:6/23/2016)... June 23, 2016 Research and Markets ... Medical Market Analysis 2016 - Forecast to 2022" report ... The report contains up to date financial data derived from ... of major trends with potential impact on the market during ... market segmentation which comprises of sub markets, regional and country ...
(Date:6/23/2016)... and INDIANAPOLIS , June ... receiving a Lilly Diabetes Tomorrow,s Leaders Scholarship is any ... scholarship winners, announced today online at www.diabetesscholars.org ... type 1 diabetes stand in the way of academic ... supported the Foundation,s scholarship program since 2012, and continues ...
Breaking Medicine Technology: