Navigation Links
Cell death pathway linked to mitochondrial fusion
Date:1/24/2011

New research led by UC Davis scientists provides insight into why some body organs are more susceptible to cell death than others and could eventually lead to advances in treating or preventing heart attack or stroke.

In a paper published Jan. 21 in the journal Molecular Cell, the UC Davis team and their collaborators at the National Institutes of Health and Johns Hopkins University report that Bax, a factor known to promote cell death, is also involved in regulating the behavior of mitochondria, the structures that provide energy inside living cells.

Mitochondria constantly split and fuse. The proteins that control the splitting of mitochondria also promote a process called apoptosis, or programmed cell death. In contrast, the proteins that control mitochondrial fusion help protect against cell death. Cell death can happen when cells are starved of oxygen, for example during a heart attack or stroke.

Yeast have a single protein that controls outer membrane fusion, but both human and mouse cells have two proteins, called MFN1 and MFN2, which control outer membrane fusion. Using mitochondria from cells derived from genetically modified "knockout" mice, Suzanne Hoppins, a postdoctoral researcher at UC Davis, and Jodi Nunnari, a professor of molecular cell biology, studied how these two proteins work together and the role specific genes play in that process.

The research team discovered that these proteins combine with themselves or each other to form a tether between two mitochondria, leading to fusion. All three combinations -- MFN1/MFN1, MFN1/MFN2 and MFN2/MFN2 -- can promote membrane fusion, but the combination of MFN1/MFN2 is by far the most efficient, Hoppins said.

Hoppins also found that a soluble form of Bax, a protein that triggers apoptosis, can also stimulate mitochondria to fuse. It acts only through the MFN2/MFN2 combination, she found.

The form of Bax that promotes mitochondrial fusion is different from the type that leads to cell death, Nunnari said. Bax leads to cell death when it inserts itself in the mitochondrial membrane. In its soluble, free-floating form, it causes mitochondria to fuse instead.

MFN1 and MFN2 are found in different amounts in different body organs. MFN2 is more abundant in the brain and heart -- tissues where cell death can have disastrous consequences.

The paper shows how MFN2 could act to protect the brain or heart from cell death, by using Bax in a different form, Nunnari said.

"This shows that the fusion machine is both positively and negatively regulated in cells and opens doors to finding the regulatory mechanisms and discovering ways to increase or decrease the sensitivity of cells to apoptosis," Hoppins said. That could lead to new drugs that save cells, for heart disease and stroke, or that kill cells, for cancer.


'/>"/>

Contact: Andy Fell
ahfell@ucdavis.edu
530-752-4533
University of California - Davis
Source:Eurekalert

Related biology news :

1. Breast cancer cells recycle to escape death by hormonal therapy
2. Genes that control cell death fingered in age-related hearing loss
3. Caltech geobiologists discover unique magnetic death star fossil
4. Forced evolution: Can we mutate viruses to death?
5. Drops in blood oxygen levels may be key to sudden death in some epilepsy patients
6. New technology aims to reduce maternal and neonatal deaths
7. Fewer deaths with preventive antibiotic use
8. Burnham researchers discover on switch for cell death signaling mechanism
9. Study helps explain connection between sleep apnea, stroke and death
10. Stroke Belt deaths tied to non-traditional risk factors
11. Jefferson scientists discover a key protein regulator of inflammation and cell death
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:3/10/2016)... March 10, 2016 --> ... research report "Identity and Access Management Market by Component ... and Governance), by Organization Size, by Deployment, by Vertical, ... by MarketsandMarkets, The market is estimated to grow from ... by 2020, at a Compound Annual Growth Rate (CAGR) ...
(Date:3/8/2016)... March 8, 2016   Valencell , the ... announced it has secured $11M in Series D ... a new venture fund being launched by UAE-based ... from existing investors TDF Ventures and WSJ Joshua ... continue its triple-digit growth and accelerate its pioneering ...
(Date:3/2/2016)... 2, 2016 http://www.researchandmarkets.com/research/cmt3hk/global_biometrics ... "Global Biometrics as a Service Market ... --> http://www.researchandmarkets.com/research/cmt3hk/global_biometrics ) has announced ... as a Service Market 2016-2020" report ... Research and Markets ( http://www.researchandmarkets.com/research/cmt3hk/global_biometrics ) has ...
Breaking Biology News(10 mins):
(Date:4/27/2016)... ... 27, 2016 , ... Most consumers engage with biometrics technology ... secure access, voice recognition for hands-free communication, and facial recognition to help organize ... technology today. But if they asked Joey Pritikin, Vice President of Marketing ...
(Date:4/27/2016)... ... April 27, 2016 , ... The Board of ... appointment of John Tilton as Chief Commercial Officer.  Mr. Tilton joined Biohaven from ... founding commercial leaders responsible for the commercialization of multiple orphan drug indications. ...
(Date:4/27/2016)... , ... April 27, 2016 , ... ... simultaneous preclinical PET (Positron Emission Tomography) and MRI (Magnetic Resonance Imaging) in existing ... disease and testing novel treatments in small animal subjects. Simultaneous PET/MRI imaging offers ...
(Date:4/27/2016)... 2016 MedDay, a biotechnology company focused ... appointment of Catherine Moukheibir as Chairman of its Board of ... Jean Jacques Garaud , who contributed to the rapid development ... Catherine started her career in strategy consulting and ... London .  She held C-Suite level roles in ...
Breaking Biology Technology: