Very excited to share our latest, now out in @eLife:

Golgi compartments enable controlled biomolecular assembly using promiscuous enzymes. https://elifesciences.org/articles/49573 ">https://elifesciences.org/articles/...

I& #39;m really proud of this paper. I first heard about glycan synthesis in the Golgi precisely ten years ago (here& #39;s my notebook from the @KITP_UCSB evolutionary cell biology meeting in 2010) but I didn& #39;t know enough about cells and enzymes back then to formulate a good problem.

Then @anjali_jaiman took this on as her PhD project. Whenever I thought we couldn& #39;t make progress, Anjali would go back to the data and see hints of a deeper solution. The result is an absolute tour-de-force by Anjali: we classified all enzymatic sources of glycan variability.

The glycans attached to a particular protein type can vary. This molecule-to-molecule variability is called "microheterogeneity". It happens because the enzymes that build glycans are promiscuous. See our new review in #BiochemSocTrans: https://portlandpress.com/biochemsoctrans/article/doi/10.1042/BST20190651/225299/Promiscuity-and-specificity-of-eukaryotic">https://portlandpress.com/biochemso...

We found that variability happens because of "bad" interactions between enzymes in a reaction compartment. When we break up these bad interactions, by splitting enzymes across Golgi compartments, variability is eliminated and more kinds of glycans can be specifically synthesized.

In summary:

The enzymes in Golgi compartments
build glycans as protein adornments.
But the enzymes are sloppy,
so cells need the Golgi,
to assemble the glycans that are meant.