HRMEM

Structural insights into γH2Ax containing nucleosomes - PubMed The phosphorylation of the histone variant H2AX on the nucleosome, yielding γH2AX, acts as a 'master control switch', signaling the recruitment of DNA repair factors at DNA double-stranded break sites. This phosphorylation is recognized by BRCA1 carboxy-terminal (BRCT) domains of specific repair pro …

Check out this paper, for which we collected data for Rashmi Panigrahi and the Glover lab at UAlberta! We needed a tilted collection to get the side views of these nucleosomes, and it was a lot of fun working with our colleagues from another province!
pubmed.ncbi.nlm.nih.gov/41123210/ #cryoEM ❄️🔬🇨🇦

We are excited to share the recent paper from @filipvanpetegem.bsky.social featuring cryo-EM structures of the KCNQ1 potassium channel collected at HRMEM!
#cryoEM #structuralbiology
www.nature.com/articles/s41...

Our cryo-EM structure of the intermediate state of the KCNQ1 potassium channel is out. Collaborative effort with the David Fedida and Luca Maragliano labs. Cryo-EM work spearheaded by Efthimios Kyriakis, PhD

www.nature.com/articles/s41...

Liposomal lipid nanoparticles for extrahepatic delivery of mRNA - Nature Communications Long-circulating, transfection-competent LNP-mRNA systems are key for effective extrahepatic delivery. Here, authors show that LNPs with high bilayer lipid ratios yield high mRNA encapsulation, prolon...

HRMEM is excited to share this new paper from the Cullis lab! Congrats to Miffy Cheng et al!
www.nature.com/articles/s41...

Cell envelope diversity and evolution across the bacterial tree of life - Nature Microbiology This Review discusses the diversity of cell envelope architectures across major bacterial phyla and highlights conserved features found in diderm lineages.

HRMEM is excited to spotlight this excellent review of cell envelope diversity and evolution from HRMEM cryoET user Eltiza Tocheva (@elitzatocheva.bsky.social‬) and team.

www.nature.com/articles/s41...

A magnetic separation method for isolating and characterizing the biomolecular corona of lipid nanoparticles | PNAS Lipid nanoparticle (LNP) formulations are a proven method for the delivery of nucleic acids for gene therapy as exemplified by the worldwide rollou...

HRMEM is happy to spotlight this exciting work, which applied a magnetic separation technique to characterize LNP bimolecular coronas.

Congratulations to Valentina Francia, Yao Zhang and colleagues from the Cullis lab at UBC.

We are proud to have supported this work! 🔬

doi.org/10.1073/pnas...

SBGrid webinars are hosted with partial support from the NIH R25 Continuing Education for Structural Biology Mentors #GM151273, in collaboration with Co-PI J... CryoDRGN

In case you missed our May webinar, it is now available!! Ellen Zhong from Princeton University presented CryoDRGN-AI.

Topic: CryoDRGN-AI: Neural ab initio reconstruction of challenging cryo-EM and cryo-ET datasets
Host: Pete Meyer
Recorded on: May 20, 2025

buff.ly/jKjWTOa

#SBGridWebinars

#structuralbiology
#drugdiscovery #cryoEM #STEM #pharmacology #UBC

Structural and electrophysiological basis for the modulation of KCNQ1 channel currents by ML277 - Nature Communications KCNQ1 channels are active in heart, brain and gut. Functional loss causes epilepsy and sudden arrhythmic death. Here, authors describe a key activator drug binding site, explaining isoform and drug se...

HRMEM is proud to spotlight this structure of the cardiac potassium channel, KCNQ1, bound to its activator, ML277!

Shout to Katrien Willegems, Jodene Eldstrom, Efthimios Kyriakis, Fariba Ataei and researchers from the Fedida and Van Petegem Labs at UBC! 🔬🫀🧬

#cryoEM

www.nature.com/articles/s41...

#cryo-EM #STEM

Structure of calcineurin bound to PI4KA reveals dual interface in both PI4KA and FAM126A Phosphatidylinositol 4-kinase alpha (PI4KA) maintains the phosphatidylinositol 4-phosphate (PI4P) and phosphatidylserine pools of the plasma membrane.…

HRMEM is happy to spotlight this structure of calcineurin bound to PI4KA determined by Alexandria Shaw and colleagues from the Burke Lab at the University of Victoria and the Yip Lab at UBC!

We are proud to have provided the electron microscopy for this work!

Read more:
doi.org/10.1016/j.st...

Laser-Induced Rehydration of Cryo-Landed Proteins Restores Native Structure The use of native mass spectrometry (MS) to land biological molecules for subsequent cryogenic electron microscopy (cryoEM) imaging and three-dimensional reconstruction has gained momentum in recent y...

Mass Spec + lasers + cryoEM = COOL SCIENCE!

New research from @coonlab.bsky.social and the Grant Lab combines mass spec to land proteins on TEM grids, a laser to restore protein structure, and cryoEM imaging and analysis to produce 3D reconstructions.

www.mcponline.org/article/S153...

Hey #TeamTomo,
Ever been in need of a tutorial about the fundamentals of cryo-electron tomography? From preprocessing raw frames to high-res subtomogram averaging?
That's why @florentwaltz.bsky.social and I made this website!

tomoguide.github.io

Follow the thread 1 /🧵
#CryoET #CryoEM 🔬🧪

Cryo-EM structures of the ABCA4 importer reveal mechanisms underlying substrate binding and Stargardt disease - Nature Communications ABCA4 is an ATP-binding cassette (ABC) transporter that flips N-retinylidenephosphatidylethanolamine (N-Ret-PE) to the cytoplasmic leaflet of photoreceptor membranes. ABCA4 mutations are associated wi...

We are happy to spotlight these structures of human ABCA4, a crucial transporter for ocular function, determined by Jéssica Fernandes Scortecci and colleagues from the Molday and Van Petegem Labs at UBC! 🔬

We are happy to have supported this work! #cryoEM

Read more:
www.nature.com/articles/s41...

The cell envelope of Thermotogae suggests a mechanism for outer membrane biogenesis | PNAS The presence of a cell membrane is one of the major structural components defining life. Recent phylogenomic analyses have supported the hypothesis...

Cryo-ET of Thermotoga maritima in a study led by Danielle Sexton and colleagues from the Tocheva Lab at UBC broadened our understanding of outer membrane biogenesis!

Shout out to @elitzatocheva.bsky.social !

Read more about this awesome work supported by HRMEM here:

www.pnas.org/doi/10.1073/...

🚨New preprint!🚨 #teamtomo
We expanded Surface Morphometrics to quantify membrane thickness from cryo-ET—revealing local variation across organelles.

Led by the lab’s first grad student, @mmedina300kv.bsky.social (defending Monday! 🍾) w/ @attychang.bsky.social @hamid13r.bsky.social & @tomo.science

Determination of the interior pH of lipid nanoparticles using a pH-sensitive fluorescent dye-based DNA probe Lipid nanoparticles (LNPs) containing ionizable cationic lipids are proven delivery systems for therapeutic nucleic acids, such as small interfering R…

Bin Zhao and colleagues from the Cullis Lab at UBC have developed a technique to determine the pH inside LNPs using a pH-sensitive fluorescent dye-based DNA probe. 🧬🔬

HRMEM is happy to have supported the electron microscopy for this exciting research!

Read more :

doi.org/10.1016/j.bi...

Ultracool microscopy yields a sharper look at proteins After years of frustration, researchers learn how to sharpen molecular images with liquid helium

"Not only will it provide sharper details of proteins and other molecules imaged with cryo-EM," says
@berkeleylab.lbl.gov 's Peter Denes, "but it should enable microscopists to image even proteins roughly half the size of what is currently possible."

Cryo-EM investigation of ryanodine receptor type 3 - Nature Communications Ryanodine Receptor type 3 mediates ER Ca2+ release in different cell types. Here, the authors use cryo-EM to reveal a binding site for chloride and two distinct sites for ATP. Epileptic encephalopathy...

We are excited to spotlight this structure of the type 3 ryanodine receptor determined by Yu Seby Chen and colleagues from UBC and the University of Siena!

It was a pleasure to collaborate with the Van Petegem (@filipvanpetegem.bsky.social) Lab on this lovely work!

www.nature.com/articles/s41...

Biochemical and structural characterization of Rab3GAP reveals insights into Rab18 nucleotide exchange activity - Nature Communications Rab3GAP, a guanine nucleotide exchange factor for Rab18, regulates membrane trafficking and lipid droplet metabolism. The authors elucidated its molecular structure, mapped its potential substrate bin...

HRMEM is happy to have supported this structure determination of Rab3GAP by Gage Fairlie, Kha Nguyen and colleagues.

Congratulations to the Burke Lab (@jburkevic.bsky.social )at the University of Victoria and the Yip Lab at UBC! 🔬🎉

Read more here:
www.nature.com/articles/s41...

Cryo-EM analyses unveil details of mechanism and targocil-II mediated inhibition of S. aureus WTA transporter TarGH - Nature Communications Cryo-EM illuminates atomic binding details and far-ranging conformational effects of the inhibitor targocil-II on wall teichoic acid ABC transporter TarGH, a virulence target from the antibiotic resis...

Congratulations to Franco Li, Shaun Peters and colleagues from the Strynadka Lab at UBC for their recent publication showcasing cryo-EM structures of S. aureus TarGH in the presence of targocil-II!

HRMEM is proud to have supported this work! 🔬🫶

www.nature.com/articles/s41...

People always ask me what resolution they need and I say...depends on the question you're asking. This is a really cool example of that extra resolution being meaningful!

In @justinditrani.bsky.social final postdoc paper (with contributions from many others) we show that forming/purifying vesicles (here from M. smegmatis) allows structure det'n of *endogenous* membrane proteins in their *native lipid bilayer*
🧵 on methods & TB biology...
www.pnas.org/doi/full/10....

I find the lids that screw off completely WAY more staticky than the pin lids with the little door, FWIW

Sure does :) these are homemade so not sure of the exact thickness!

Image of a lamella created in a FIB-SEM instrument. The image shows the ion beam image with the lamella appearing as a narrow head on strip with trenches either side.

Millin' like a villain

Small LEA proteins as an effective air-water interface protectant for fragile samples during cryo-EM grid plunge freezing bioRxiv - the preprint server for biology, operated by Cold Spring Harbor Laboratory, a research and educational institution

Bringing together tardigrades and #CryoEM, I love it! ❤️
www.biorxiv.org/content/10.1... 🧪

Cryo-EM analysis on magnetic beads for scarce macromolecules in heterogeneous samples bioRxiv - the preprint server for biology, operated by Cold Spring Harbor Laboratory, a research and educational institution

OK this is COOL i love it
www.biorxiv.org/content/10.1...

A very cool method by Bonnie Murphy's lab to map elements for cryo-EM. The method, named REEL-EM, makes use of electron-energy loss spectroscopy. Honored to have contributed to this: www.biorxiv.org/content/10.1...