Chaperones articles from across Nature Portfolio

Precise protease positioning and gating of the proteasome core require the ordered assembly of 28 subunits. Cryo-EM structures of seven intermediates visualize five dedicated chaperones and three propeptides mediating step-by-step assembly of the human 20S proteasome.

Type 1 pili are crucial cell surface bacterial virulence factors. Here, the authors show that FimD is required to assemble the most stable quaternary pilus structure by ensuring that the resulting protein polymer is free of structural defects.

Maneix, Iakova and colleagues report that cyclophilin A is a chaperone for, and regulator of, intrinsically disordered proteins within haematopoietic stem and progenitor cells, with potential effects on ageing-like phenotypes and lineage commitment.

Protein complex assembly can occur co-translationally. Here, the authors uncover diverging assembly pathways and hotspot disruptions in N-terminal acetyltransferases, enzymes implicated in neurodegenerative diseases. Their model predicts co-translational assembly based on interface energy distribution.

Structural analysis and molecular dynamics of the RAF1-HSP90-CDC37 and HSP90 complexes reveal asymmetric binding of RAF1 to HSP90, a bridging role for CDC37, HSP90’s structural rearrangements, and interactions of HSP90 with unfolded regions of RAF1.

The human ATPase p97 (also known as VCP) unfolds protein substrates by translocating them through its central channel. This process is highly regulated by numerous adapter proteins. Structures of p97 in complex with the unusual adapter UBXD1 reveal how this protein coordinates p97 hexamer remodeling and ring opening by expansive interactions across multiple p97 protomers.

Disruption of ribosome assembly results in the accumulation of aggregation-prone ‘orphaned’ ribosomal proteins that are toxic to cells if left unchecked. A study finds that cells store such ribosomal proteins during heat shock to enable a quick recovery of ribosome assembly after the removal of this stress.

Molecular chaperones establish essential protein-protein interaction networks. Modified versions of these assemblies are generally enriched in certain maladies. A study published in Nature Communications used epichaperomics to identify unique changes occurring in chaperone-formed protein networks during mitosis in cancer cells.

Complexity is a hallmark of biological systems, but scientific experiments are typically conducted in simplified conditions. Now, diverse polymers that mimic the local environments of complex biological mixtures have been shown to improve protein folding, stability and function.

FG-nucleoporins of the nuclear pore complexes form a permeability barrier between the nucleus and the cytosol. FG-nucleoporins contain disordered regions and are prone to aggregation. Two studies identify the chaperone DNAJB6 as a key factor that prevents aggregation of FG-nucleoporins and assists in the biogenesis of nuclear pore complexes.