Volume 27 Issue 11, November 2020

In situ structures of the spirochete flagellar motor by cryo-ET reveal two distinct modes of interactions between the rotor ring and stator units. Together with new cryo-EM structures of the isolated stator units, this work provides insights into the mechanisms of torque generation and directional switch.

Three recent studies report cryo-EM structures of amyloid fibrils of islet amyloid polypeptide (IAPP), which are linked to type 2 diabetes (T2D) pathogenesis. The results shed light on the structural basis of IAPP fibril formation, reveal remarkable similarities between IAPP and Aβ fibrils and will inform the design of anti-amyloid drugs in T2D and Alzheimer’s disease (AD).

A cryo-EM structure reveals how nucleation-promoting factor Dip1 activates Arp2/3 complex and shows the actin-related proteins in Arp2/3 in a conformation that mimics a filamentous actin dimer, thus templating nucleation.

Cryo-EM structures of Rag GTPases in complex with Ragulator and the cytoplasmic tail of the lysosomal solute carrier SLC38A9 show how SLC38A9 promotes Rag dimer activation, essential for mTORC1 recruitment to the lysosomal membrane.

Crystal structures of BAK core domain dimers suggest a mechanism by which lipids contribute to the oligomerization of BAK, which is essential for BAK-mediated permeabilization of the mitochondrial outer membrane.

Live-cell imaging of tagged genomic loci reveals clusters of distal enhancers in close proximity to target genes, creating a nanoenvironment wherein site-specifically recruited enhancer-associated regulatory factors activate transcription.

In situ cryo-ET analyses of Borrelia burgdorferi flagellar motors locked in clockwise or counterclockwise rotation provide insights into rotational switching.

Cryo-EM structures of diabetes-related amyloids formed by wild-type human amylin (IAPP) and its S20G variant reveal a mode for surface-templated fibril growth.

A SNAP-tag approach to monitoring histone dynamics at transcriptionally active sites in human cells identifies two distinct HIRA-dependent pathways that direct H3.3 deposition or retention.

Cryo-EM structures of Cas12i in multiple functional states provide insights that might facilitate the manipulation of this type V CRISPR-Cas endonuclease for genome editing applications.

Cryo-EM structures of the entire mammalian F1Fo ATPase reveal several new features and details on the proton translocation pathway and suggest a model for the opening of the permeability transition pore.

DUOX1 is an NADPH oxidase involved in thyroid hormone production and innate host defense. Cryo-EM structures of murine DUOX1 bound to maturation factor DUOXA1 provide insights into regulation and activation of this enzyme.