The findings, which appear in the October 2 edition of Cell, also provide a new level of understanding of the regulation of mitochondrial genes and open new avenues of inquiry into the interplay between mitochondrial function, diet and energy metabolism.
Mitochondria act as the “powerhouse” of the cells. It is well known that mitochondrial function worsens with age in many species and in humans with Type II diabetes and obesity. “Our study shows that dietary restriction can enhance mitochondrial function hence offsetting the age-related decline in its performance,” said Buck faculty member Pankaj Kapahi, PhD, lead author of the study.
The research provides the first genome-wide study of how proteins are translated under dietary restriction in any organism. The researchers report the unexpected finding that while there is a reduction in protein synthesis globally with the low protein diet, the activity of specific genes involved in generating energy in the mitochondria are increased, Kapahi said. That activity, which takes place at the level of conversion of RNA to protein, is important for the protective effects of dietary restriction, Kapahi said. “There have been correlative studies that show mitochondria change with dietary restriction, this research provides a causal relationship between diet and mitochondrial function,” he said.
The study describes a novel mechanism for how mitochondrial genes are converted from RNA to protein by a particular protein (d4EBP). Flies fed a low protein diet showed an uptick in activity of d4EBP, which is involved in a signaling pathway that mediates cell growth in response to nutrient availability called TOR (target of rapamycin). The research showed that d4EBP is necessary for lifespan extension upon dietary restriction. When the activity of the protein was genetically “knocked out” the flies did not live longer, even when fed the low protein diet. When the activity of d4EBP was enhanced, lifespan was extended, even when the flies ate a rich diet.
The research calls into question the health benefits of high-protein diets which are often used by humans to lose weight Kapahi said. The long-term impacts of such diets have not been examined in humans; they are likely to be harmful, he said. “In flies, we see that the long-lived diet is a low protein diet and what we have found here is a mechanism for how that may be working,” Kapahi said.
The study provides a significant advance in understanding the role of 4EBP, a downstream molecular target of TOR, which mediates a switch in metabolism to extend lifespan, Kapahi said. A recent study appearing in the Nature showed that feeding rapamycin (an antibiotic used to prevent the rejection of organ and bone marrow transplants) to mice inhibited TOR and extended their lifespan. The Buck Institute study implies an important role for 4EBP and mitochondrial function as excellent targets to explore their role in lifespan extension in mammals, Kapahi said.
Kris Rebillot | Newswise Science News
Meadows beat out shrubs when it comes to storing carbon
23.11.2017 | Norwegian University of Science and Technology
Migrating Cells: Folds in the cell membrane supply material for necessary blebs
23.11.2017 | Westfälische Wilhelms-Universität Münster
Heat from the friction of rocks caused by tidal forces could be the “engine” for the hydrothermal activity on Saturn's moon Enceladus. This presupposes that...
The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.
Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....
The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.
Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...
Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.
That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...
Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.
During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....
15.11.2017 | Event News
15.11.2017 | Event News
30.10.2017 | Event News
23.11.2017 | Information Technology
23.11.2017 | Physics and Astronomy
23.11.2017 | Life Sciences