New work from the Imperi group #Roma3 study phospholipid traffic in Pseudomonas. Four out of the seven AsmA homologs (tamB, yhdP, ydbH, PA4735) are redundantly essential (at least one is required).

There is rescue by lower LPS delivery, showing balance between the 2 OM leaflets.

There's a new paper from the Olof Idevall-Hagren group (Uppsala) who show that insulin granules form contacts with the ER where OSBP is recruited (Ca2+ and pH- dependent) to exchange granule PI(4)P for ER cholesterol, hence allowing normal insulin secretion.

We have 10 articles in a Special Collection on VPS13 and Bridge-Like Lipid Transfer Proteins: six original research and four reviews. Read our Editorial to find out more about them and to access them one by one.

journals.sagepub.com/doi/10.1177/25…

The team of Yang Zhang (Chengdu) have created a database of membrane contact sites - 44 of them! - with more than 600 low-throughput MCS proteins, as well as many more documented in high-throughput experiments - either by proximity ligation or mass spec.

nature.com/articles/s4159…

We have a new, comprehensive review from Daniel Lévy and Dezi Manuela (@institut_curie) on Cryo-Electron Microscopy of Membrane Contact Sites.

Multiple powerful techniques are only applied by a few groups currently. The review aims to widen appreciation to increase uptake.

Hey, everybody. Come to this great conference on ALL matters contact-site-ish: run by Biochemical Society

Great speakers from Europe and beyond. Put the date September 23-25 2024 in your diary
And register online at bit.ly/Membrane24.

🙏retwt

Chris Miller's team (King's, London 1st author Andrea Markovinovic) show that Ca2+ & synaptic defects resulting from aberrant TDP43, as found in FTD/ALS, can be rescued by stimulating VAPB-PTPIP51 ER-mitochondria bridging complexes.

e.g. by inhibiting GSK3b

ncbi.nlm.nih.gov/pmc/articles/P…

The team of Gerry Hammond (Pittsburgh) answer a controversy about whether OSBP has dominant effects on levels of Golgi PI4P. Answer: Yes!

journals.sagepub.com/doi/full/10.11…

This suggests that beyond a role in sterol forward traffic, OSBP regulates other Golgi PI4P-dependent functions.

Now Maria Bohnert & team (Muenster) show LDO proteins (yeast homologs of promethin) are the lipid droplet components of the bridge to the vacuole

They also show Ldo45 (not Ldo16) binds the lanosterol/PI transfer protein Pdr16 (=Sfh3)

+ see parallel paper:cell.com/developmental-…

Contact will be sponsoring the upcoming Yeast Lipid Conference LST @ Saarland University, Homburg, Germany.

If you need more info, contact the organisers Robert Ernst and Mike Renne (yeastlipidconference.com or email [email protected]).

Early registration discounts (10-25%) for the next 9 days.

There's a new paper from Marisa Brini and Calì_Lab (@PNC_UniPD) showing that lyosome-mitochondrial contact is required to channel Ca2+ and keep it low locally.
High levels of alpha-synuclein inhibit this, leading to TFEB activation and aberrant signalling

Exciting discovery from Sarah Cohen (@UNC)
about the disease causing allele of ApoE: in astrocytes it affects the internal lipid stores (not just lipoprotein traffic to the outside).
A portion remains in the cytoplasm & modulates LD formation, with E4 less cytoprotective.

We have a new paper György Csordás, David Weaver, Péter Várnai and György Hajnóczky Thomas Jefferson University showing for the 1st time that Ca2+ uptake by mitochondria is supra-linear: it amplifies release from the ER store by IP3R
journals.sagepub.com/doi/full/10.11…

MAMs in action!

How lipid droplets contact the yeast vacuole is shown by Irene Álvarez Guerra in the @Buttnerlab (Stockholm): LDO proteins bind to Vac8 in competition with other ligands such as Nvj1, Atg13.

It will be interesting to see which of the many animal ARM proteins like Vac8 act similarly.

We have a News & Views about store-operated Ca2+ entry from FlyCalcium (Bengaluru, India) that covers new data from her own group that shows IP3-binding to IP3R enhances STIM–Orai interactions and SOCE not only via ER-Ca2+ release, but also another way - mechanism still unknown.

We have a new paper from the Gerry Hammond lab (Pittsburgh) who show that a major player in removing PI4P from the plasma membrane is ORP2 NOT at membrane contact sites (along with ORP5).

journals.sagepub.com/doi/full/10.11…

'non-constrained transfer mechanism': every paradigm has its day

Another lipid transfer function found for Vps13 in yeast by Sho Suzuki (he/him) et al Cornell MBG (Emr Lab).

Congratulations to Sarah Cohen (@UNC) for their new paper on dimerization-dependent fluorescent protein probes (ddFPs) to report membrane contact.

This method can be adapted to simultaneously monitor 2 contacts if they share a single organelle.

Secretory cargoes are sorted in the trans-Golgi network (TGN) in a Ca2+-dependent, cargo receptor-independent manner. What is the Ca2+ source? Nice paper @MBoCjournal from Julia von Blume von Blume lab suggests IP3R transfers Ca2+ at ER-TGN contact sites.
molbiolcell.org/doi/abs/10.109…

This year's Yeast Lipid Conference includes major contributions on inter-organelle communication at contactss, with a plenary talk from Benoit Kornmann (Oxford) and more. It's a great little conference about a great little organism.

'the awesome power of yeast lipid conference'