Your body recycling itself -- captured on film (w/ Video)

Sep 13, 2010
This image shows UBR-box recognition of an arginine residue at the beginning of a protein (blue) targeted for degradation. The structural integrity of the UBR box depends on zinc (grey) and a histidine residue (red) that is mutated in Johanson-Blizzard syndrome. Reconnaissance d’un résidu d’arginine au codon d’initiation d’une protéine (en bleu) ciblée pour faire l’objet d’une dégradation. L’intégrité structurale de la boîte de dégradation de la protéine ubiquitine-ligase E3 dépend du zinc (en gris) et d’un résidu d’histidine (en rouge) qui subit une mutation dans le cas de syndrome de Johanson-Blizzard. Credit: Department of Biochemistry, McGill University. Département de biochimie, Université McGill.

Our bodies recycle proteins, the fundamental building blocks that enable cell growth and development. Proteins are made up of a chain of amino acids, and scientists have known since the 1980s that first one in the chain determines the lifetime of a protein. McGill researchers have finally discovered how the cell identifies this first amino acid - and caught it on camera.

"There are lots of reasons cells recycle proteins - fasting, which causes loss of muscle, growth and remodeling during development, and normal turnover as old proteins are replaced to make new ones," explained lead researcher, Dr. Kalle Gehring, from McGill's Department of Biochemistry.

"One way that cells decide which proteins to degrade is the presence of a signal known as an N-degron at the start of the . By X-ray crystallography, we discovered that the N-degron is recognized by the UBR box, a component of the cells' recycling system."

This video is not supported by your browser at this time.
This video shows UBR-box recognition of an arginine residue at the beginning of a protein (blue) targeted for degradation. The structural integrity of the UBR box depends on zinc (grey) and a histidine residue (red) that is mutated in Johanson-Blizzard syndrome. Reconnaissance d’un résidu d’arginine au codon d’initiation d’une protéine (en bleu) ciblée pour faire l’objet d’une dégradation. L’intégrité structurale de la boîte de dégradation de la protéine ubiquitine-ligase E3 dépend du zinc (en gris) et d’un résidu d’histidine (en rouge) qui subit une mutation dans le cas de syndrome de Johanson-Blizzard. Credit: Département de biochimie, Université McGill. Department of Biochemistry, McGill University.

The powerful technique can pinpoint the exact location of atoms and enabled the team to capture an image of the UBR box, providing insight to this incredibly tiny yet essential part of our bodies' chemical mechanics.

Aside from representing a major advance in our understanding of the life cycle of proteins, the research has important repercussions for Johanson-Blizzard syndrome, a rare disease that causes deformations and . This syndrome is caused by a mutation in the UBR box that causes it to lose an essential zinc atom. Better understanding of the structure of the UBR box may help researchers develop treatments for this syndrome.

Explore further: Malaria transmission linked to mosquitoes' sexual biology

Related Stories

Unfolding 'nature's origami'

Mar 02, 2009

Sometimes known as "nature's origami", the way that proteins fold is vital to ensuring they function correctly. But researchers at the University of Leeds have discovered this is a 'hit and miss' process, with proteins potentially ...

Study opens a new door to understanding cancer

Aug 09, 2007

An in-depth understanding of the mechanisms that trigger cancer cell growth is vital to the development of more targeted treatments for the disease. An article published in the August 3 issue of Molecular Cell provides a key ...

Research breakthrough for the protein factories of tomorrow

Sep 22, 2006

Using a kind of molecular ‘hip joint operation,’ researchers at Uppsala University have succeeded in replacing a natural amino acid in a protein with an artificial one. This step forward opens the possibility of creating ...

Recommended for you

Malaria transmission linked to mosquitoes' sexual biology

17 hours ago

Sexual biology may be the key to uncovering why Anopheles mosquitoes are unique in their ability to transmit malaria to humans, according to researchers at Harvard T. H. Chan School of Public Health and University of Per ...

Intermediary neuron acts as synaptic cloaking device

18 hours ago

Neuroscientists believe that the connectome, a map of each and every connection between the millions of neurons in the brain, will provide a blueprint that will allow them to link brain anatomy to brain function. ...

Skeleton of cells controls cell multiplication

18 hours ago

A research team from Instituto Gulbenkian de Ciencia (IGC; Portugal), led by Florence Janody, in collaboration with Nicolas Tapon from London Research Institute (LRI; UK), discovered that the cell's skeleton ...

New study shows safer methods for stem cell culturing

Feb 25, 2015

A new study led by researchers at The Scripps Research Institute (TSRI) and the University of California (UC), San Diego School of Medicine shows that certain stem cell culture methods are associated with increased DNA mutations. ...

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.