Researchers Capture Images that Illuminate One of Cell's Mysteries

July 18, 2008 By Bill Hathaway

( -- Within human cells, tiny membrane-bound compartments called vesicles shepherd biomolecules from place to place.

How these vesicles form, move and finally fuse to deliver cargo at a particular destination largely remains a mystery, now being investigated by Yale researchers Karin Reinisch and Susan Ferro-Novick.

The scientists, both of the Department of Cell Biology, have focused on understanding the molecular basis for the final steps of cargo delivery, a process believed to be important in specifying the correct delivery address for a particular vesicle.

In the June issue of the journal Cell, they describe how they used X-ray crystallography to visualize a key step in this process.

A decade ago, Ferro-Novick’s lab first discovered the large multi-protein complex known as TRAPPI that plays a role in tethering a vesicle to its target. In a technically demanding feat, the team captured an image of TRAPPI as it activates a regulatory protein within the cell. Activation of the protein, known as Rab GTPase Ypt1, is a crucial step leading to the fusion of the vesicle. The study provides a framework for understanding how the many proteins involved in vesicle docking cooperate.

Large protein assemblies are difficult to crystallize and to visualize at an adequate level of detail, but the team led by Yiying Cai, lead author of the study, was able to overcome those technical hurdles.

“We were able to get these results only because Yiying was relentless in preparing samples of sufficient quality,” Reinisch says.

Other team members currently in the Department of Cell Biology include Darina Lazarova, Shekar Menon and Anthony Sclafani. Key contributions were also made by Harvey Chin in the lab of Enrique De La Cruz in the Department of Molecular Biology and Biophysics.

Provided by Yale University

Explore further: Protein reactions identified with subatomic resolution—why some switch proteins are slower than others

Related Stories

Keeping cells in good shape

September 28, 2015

People often talk about how important it is to stay in shape, something humans usually can accomplish with exercise and a healthy diet, and other habits. But chances are, few of us ever think about the shape of our individual ...

Scientists discover new system for human genome editing

September 25, 2015

A team including the scientist who first harnessed the revolutionary CRISPR-Cas9 system for mammalian genome editing has now identified a different CRISPR system with the potential for even simpler and more precise genome ...

Recommended for you

Detecting HIV diagnostic antibodies with DNA nanomachines

October 7, 2015

New research may revolutionize the slow, cumbersome and expensive process of detecting the antibodies that can help with the diagnosis of infectious and auto-immune diseases such as rheumatoid arthritis and HIV. An international ...


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.