"Membrane proteins are first manufactured inside the cell and transported to an organelle called the endoplasmic reticulum (ER). There, the proteins are inserted into the membrane, where they carry out myriad functions. For many membrane proteins, this insertion process relies on a complicated structure known as the ER membrane protein complex (EMC). The EMC is evolutionarily ancient, found broadly in eukaryotic cells from fungus to humans. And it is exploited by viruses (potentially including the novel coronavirus responsible for the COVID-19 pandemic) which use it to construct and transport some of their own viral proteins in an infected organism. ...
Now, Caltech scientists have seen the EMC for the first time, with a technique called single-particle cryo-electron microscopy—through which samples are frozen, imaged at the atomic level, and then computationally reconstructed in fine detail. ...
The EMC was discovered about 10 years ago, but until recently, no techniques were available that could image its structure. ... to work in collaboration with Caltech's cryo-electron microscopy facility (one of the few such facilities in the world) ..."
"A defining step in the biogenesis of a membrane protein is the insertion of its hydrophobic transmembrane helices into the lipid bilayer. The nine-subunit ER membrane protein complex (EMC) is a conserved co- and post-translational insertase at the endoplasmic reticulum. We determined the structure of the human EMC in a lipid nanodisc to an overall resolution of 3.4 Å by cryo-electron microscopy, permitting building of a nearly complete atomic model."
Caltech Researchers Solve Structure of Crucial Cellular Component | www.caltech.edu Understanding the atomic details of the endoplasmic reticulum membrane protein complex
Here is the link to the underlying research paper: Structural basis for membrane insertion by the human ER membrane protein complex
There you find a lot of supplementary material has been provided with the paper like several videos.
No comments:
Post a Comment