Cover Image: May 2008 Scientific American Magazine See Inside

How Cells Clean House [Preview]

Worn-out proteins, malfunctioning organelles, invading microorganisms: all are swept up by tiny internal "vacuum cleaners" that keep a living cell healthy. If the process, called autophagy, can be kept in good working order, aging itself might be delayed















Share on Tumblr



Image: Adam Questell

In Brief

  • Inside the cytoplasm of a living cell, organelles called autophagosomes continually engulf bits of cytoplasm, along with damaged cell parts and invading bacteria and viruses. The “sweepings” are carried to digestive organelles for breakup and recycling. The process is called autophagy.
  • Cell biologists are learning about autophagy in great detail by tracing the protein signals that drive and control the process.
  • A fuller understanding of auto­phagy is opening up new options for treating cancer, infectious disease, immune disorders and dementia, and it may one day even help to slow

Every once in a while biologists come to realize that what was at one time regarded as a minor and relatively obscure cellular process is, in fact, of central importance. Not only is the process ubiquitous, but by virtue of that ubiquity it also plays a role in a broad range of normal and disease states. So it was with the discovery of the role of nitric oxide in the circulatory system, a discovery that led to a Nobel Prize, as well as to many beneficial drugs. Now another formerly obscure process known as autophagy is suddenly claiming extraordinary scientific attention.

In basic outline, autophagy (from the Greek, meaning “self-eating”) is simple enough. Within every cell but outside the nucleus lies the cytoplasm, a kind of formless jelly supported by a skeletal matrix, in which a vast and intricate population of large molecules, or macromolecules, and specialized functional subunits called organelles is suspended. The workings of the cytoplasm are so complex—rather like some of today’s computer systems—that it is constantly becoming gummed up with the detritus of its ongoing operations. Autophagy is, in part, a cleanup process: the trash hauling that enables a cell whose cytoplasm is clotted with old bits of protein and other unwanted sludge to be cleaned out.


This article was originally published with the title How Cells Clean House.



Subscribe     Buy This Issue

Already a Digital subscriber? Sign-in Now
If your institution has site license access, enter here.

1 Comments

Add Comment
View
  1. 1. champagna1 02:45 PM 11/19/08

    Very nice

    Reply | Report Abuse | Link to this
Leave this field empty

Add a Comment

You must sign in or register as a ScientificAmerican.com member to submit a comment.
Click one of the buttons below to register using an existing Social Account.

More from Scientific American

See what we're tweeting about

Scientific American Editors

More »

Free Newsletters


Get the best from Scientific American in your inbox

Solve Innovation Challenges

Powered By: Innocentive

  SA Digital

Latest from SA Blog Network

  SA Digital

Email this Article

How Cells Clean House: Scientific American Magazine

X
Scientific American Magazine

Subscribe Today

Save 66% off the cover price and get a free gift!

Learn More >>

X

Please Log In

Forgot: Password

X

Account Linking

Welcome, . Do you have an existing ScientificAmerican.com account?

Yes, please link my existing account with for quick, secure access.



Forgot Password?

No, I would like to create a new account with my profile information.

Create Account
X

Report Abuse

Are you sure?

X

Institutional Access

It has been identified that the institution you are trying to access this article from has institutional site license access to Scientific American on nature.com. To access this article in its entirety through site license access, click below.

Site license access
X

Error

X

Share this Article

X