Biologists identify key protein in cell's 'self-eating' function

Mar 11, 2008

Molecular biologists at the University of California, San Diego have found one piece of the complex puzzle of autophagy, the process of “self-eating” performed by all eukaryotic cells -- cells with a nucleus -- to keep themselves healthy.

Their finding, published in the March 11 issue of the journal Developmental Cell, is important because it allows scientists to control this one aspect of cellular autophagy, and may lead to the ability to control other selective “self-eating” processes. This, in turn, could help illuminate autophagy’s role in aging, immunity, neurodegeneration and cancer.

Biologists identify key protein in cell's 'self-eating' function

All eukaryotic cells dispose of bacteria, viruses, damaged organelles and other non-essential components through this self-eating process. A part of the cell called the lysosome engulfs and degrades subcellular detritus. The ability of cells to recycle and reuse the cellular raw materials, as well as to “re-model” themselves in response to changing conditions, allows them to adapt and survive.

Autophagy was first described about 40 years ago, but has recently become a topic of great interest in cell biology because it is linked to cell growth, development aging and homeostasis -- helping cells to maintain a balance among synthesis, degradation and recycling.

The UC San Diego researchers report in their paper that they identified a novel protein called Atg30 (one of 31 required for autophagy-related processes) from the yeast Pichia pastoris, that controls the degradation of a sub-compartment of cells, the peroxisomes.

Peroxisomes generate and dispose of harmful peroxides that are by-products of oxidative chemical reactions.

Different organelles within the cell are degraded by lysosomes when the organelles are damaged or not necessary, said Jean-Claude Farré, the biologist who identified Atg30. The team is investigating peroxisomes, and working to understand how and why they are selected by the lysosome for degradation.

What the biologists found, he said, is that “this new protein can mediate peroxisome selection during pexophagy – that is, it is necessary for pexophagy, but not for other autophagy-related processes.”

Suresh Subramani, a professor of biology who headed the team, said they have established that Atg30 is a “key player” in the selection of peroxisomes for delivery to “the autophagy machinery” for re-cycling.

“For the first time, we can use a protein to control the process,” Subramani said. “It’s an important step in understanding the workings of cells.”

Source: University of California - San Diego

Explore further: Insect mating behavior has lessons for drones

Related Stories

Architects to hatch Ecocapsule as low-energy house

18 hours ago

Where people call home depends on varied factors, from poverty level to personal philosophy to vanity to community pressure. Ecocapsule appears to be the result of special factors, a team of architects applying ...

California farmers agree to drastically cut water use

21 hours ago

California farmers who hold some of the state's strongest water rights avoided the threat of deep mandatory cuts when the state accepted their proposal to voluntarily reduce consumption by 25 percent amid ...

Apple may deliver ways to rev up the iPad, report says

22 hours ago

MacRumors last month said that the latest numbers from market research firm IDC's Worldwide Quarterly Tablet Tracker revealed Apple stayed on as the largest vendor in a declining tablet market. The iPad ...

Recommended for you

Insect mating behavior has lessons for drones

3 hours ago

Male moths locate females by navigating along the latter's pheromone (odor) plume, often flying hundreds of meters to do so. Two strategies are involved to accomplish this: males must find the outer envelope ...

Bacterial tenants in fungal quarters

13 hours ago

Ludwig Maximilian University of Munich researchers have sequenced the genome of a bacterial symbiont hosted by a mycorrhizal fungus. Analysis of the symbiont's genetic endowment reveals previously unknown ...

Natural enzyme examined as antibiotics alternative

16 hours ago

In 1921, Alexander Fleming discovered the antimicrobial powers of the enzyme lysozyme after observing diminished bacterial growth in a Petri dish where a drop from his runny nose had fallen. The famed Scottish ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.