HOME >> BIOLOGY >> NEWS
Need oxygen? Cells know how to spend and save

in hypoxia. In low oxygen, liver, uterus, lung and colon cells all made COX4-2. The researchers then exposed mice to hypoxia for a few weeks and found that they too showed increased levels of COX4-2.

In 1992, Semenza's team had discovered a protein which they called HIF-1 (for hypoxia-inducible factor 1) that cells make in response to hypoxia. HIF-1 turns on genes that help cells survive when oxygen is low, such as during a heart attack or stroke. The researchers set out to figure out if the sensor protein HIF-1 triggers the COX-swapping.

By examining the gene control regions of COX4, they found that the HIF-1 sensor switched on COX4-2 activity when oxygen is low. And they learned that because COX4-1 already is in the mitochondria, the swap for COX4-2 occurs when the sensor turns on yet another gene that produces an enzyme to specifically chew up COX4-1. Engineering human cells to lack this enzyme and subjecting them to low oxygen, the scientists found the cells unable to rid themselves of COX4-1.

"It's remarkable that the one-celled yeast also swap COX subunits in response to hypoxia, but because they lack HIF-1, they accomplish the swap in a completely different way," says Semenza. "This suggests that adapting mitochondria to changes in oxygen levels may be a major challenge for most organisms on Earth."


'"/>

Contact: Audrey Huang
audrey@jhmi.edu
410-614-5105
Johns Hopkins Medical Institutions
5-Apr-2007


Page: 1 2

Related biology news :

1. Cells take risks with their identities
2. Cells re-energize to come back from the brink of death
3. Cells selectively absorb short nanotubes
4. Cells use noise to make cell-fate decisions
5. Cells in the lung clear the air to prevent lung damage
6. Cells passed from mother to child during pregnancy live on and make insulin
7. Cells, dyes and videotape: Online scientific methods journal incorporates multimedia
8. Cells use mix-and-match approach to tailor regulation of genes
9. Cells in mucus from lungs of high-risk patients can predict tumor development
10. Double-trouble: Cells with duplicate genomes can trigger tumors
11. Double trouble: Cells with duplicate genomes can trigger tumors

Post Your Comments:
*Name:
*Comment:
*Email:


(Date:2/8/2017)... 2017 About Voice Recognition Biometrics Voice recognition ... against a stored voiceprint template. Acoustic features of ... tone are compared to distinguish between individual voices. ... most PCs already have a microphone and can ... biometrics are most likely to be deployed in ...
(Date:2/8/2017)... Report Highlights ... The global synthetic-biology market reached nearly $3.9 billion in ... a compound annual growth rate (CAGR) of 24.0% through 2021. ... for synthetic biology. - Analyses of global market trends, with ... annual growth rates (CAGRs) through 2021. - Coverage of core ...
(Date:2/8/2017)... Report Highlights The global biosurgery ... billion in 2016 at a compound annual growth rate ... Includes - An overview of the global market for ... from 2015 and 2016, and projections of compound annual ... market on the basis of product type, source, application, ...
Breaking Biology News(10 mins):
(Date:2/24/2017)... Calif. (PRWEB) , ... February 24, 2017 , ... Chef ... and wine scene. Making stops in several cities, she gained a number of ... adventure began in Stellenbosch, a town in South Africa’s Western Cape province. It ...
(Date:2/24/2017)... , Feb. 24, 2017  Aethlon Medical, Inc. (Nasdaq: ... authored by its Chairman and CEO, Jim Joyce ... Munich Security Conference last Saturday, Bill Gates ... kill more people than nuclear weapons. Mr. Gates expressed ... U.K. intelligence agencies, that scientific terrorists have access to ...
(Date:2/24/2017)...  Driven by consumers, preference towards more natural ... growing categories, finds the recently published U.S. volume ... Multi-regional Market Analysis and Opportunities study by ... "Biotechnology actives are derived from natural ... for skin and hair care applications," explains ...
(Date:2/24/2017)... ... February 24, 2017 , ... FireflySci, Inc is an explosive small business that ... the goal of bringing their powerful cuvette and spectrophotometer calibration to the ... FireflySci is going on as they add yet another mark on the global map. ...
Breaking Biology Technology:
Cached News: