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:2/12/2016)... Opelousas, LA (PRWEB) , ... February 12, 2016 , ... ... of St. Landry and Evangeline Parishes. The purpose of these scholarships is to ... to encourage those individuals to seek employment within these two parishes. , “We ...
(Date:2/12/2016)... ... 2016 , ... Each year, the American Physical Therapy Association (APTA) offers a ... Anaheim Convention Center. Almost 10,000 physical therapists across the country are expected to attend ... about their chosen field and network with their colleagues. As in years past, ...
(Date:2/12/2016)... ... February 12, 2016 , ... ... today announced the integration of Clarity Intelligence Platform (CIP) into Cielo®, a discovery, ... real-time business intelligence (BI) to their small and medium business (SMB) clients. ...
(Date:2/12/2016)... Vail, Colorado (PRWEB) , ... February 12, 2016 , ... ... 164 ASC Industry Physician Leaders to Know in 2016 . The list consists of ... leaders nominated physicians to establish this list. , An Ambulatory Surgery Center, also ...
(Date:2/12/2016)... , ... February 12, 2016 , ... For Coast Dental ... Suzan Sweeney, RDH, and dental assistant Terrell Moore shortly before 7 a.m. to volunteer ... of dental professionals, donating their time and skills to help hundreds of uninsured and ...
Breaking Medicine News(10 mins):
(Date:2/12/2016)... Ambulances announces its first delivery in the state of ... Emergency Medical Services (EMS) consisting of four vehicles: three ... Emergency Vehicles in Lecanto, FL , USA, ... the latest in Demers, ongoing expansion of sales.  ... --> Benoit LaFortune , Executive Vice President at Demers. ...
(Date:2/12/2016)... ALISO VIEJO , Kalifornien, 12. Februar 2016 ... es mit der Aufnahme von Patienten für eine ... Embolisation von Aneurysmen („WEB") speziell für die Behandlung ... Laurent Spelle , MD, Leiter der Neuroradiologie an ... , Frankreich, und Hauptprüfarzt der CLARYS-Studie hat den ...
(Date:2/12/2016)... SAN DIEGO and SEOUL, ... -- Silicon Biosys­tems Menarini and Macrogen, Inc. today ... clinical assays and innovative procedures for precision medicine ... to combine Silicon Biosystems, DEPArray™ digital-sorting technology with ... development of tests certified under the Clinical Laboratory ...
Breaking Medicine Technology: