The delivery system for an important class of proteins in the cell membrane can be fully replicated with a mere three components, according to a new study.
Tail-anchored proteins, the molecular machines that make up approximately five percent of the membrane proteins in a cell, are known to have their own special pathway for trafficking to the membrane after construction. New research from the University of Chicago and the National Institutes of Health blending structural and functional experiments finds that these proteins can be delivered to the membrane via a simple three-part system.
This deeper understanding of the tail-anchored protein pathway could have significance for the development of new drugs and bioengineering methods. Researchers studying how other types of proteins are delivered to the membrane may also benefit from comparison with this specialized pathway as it is further manipulated and dissected.
"What we are really excited about is the prospect of having a completely defined, completely synthetic controlled system," said Robert Keenan, PhD, Assistant Professor of Biochemistry and Molecular Biology at the University of Chicago. "Now we can really start asking detailed mechanistic questions."
A team of six scientists from the University of Chicago and the National Institute of Child Health and Human Development, led by Keenan and Ramanujan Hegde, MD, Ph.D., published the findings on Wednesday in the journal Nature.
Proteins are put together by ribosomes, which read DNA instructions and link amino acids together into their final form. But many proteins must be delivered from the ribosome to the endoplasmic reticulum (ER), where they are packaged and sent to their final destination.
The majority of membrane proteins navigate this route by using the "co-translational pathway," where the ribosome builds the protein directly into the ER membrane. But tail-anchored (TA) proteins, so named becaus
|Contact: Robert Mitchum|
University of Chicago Medical Center