Mechanical effect of protein glycosylation on BiP-mediated post-translational translocation and folding in the endoplasmic reticulum

Protein targeting to the ER membrane: multiple pathways and shared machinery

The endoplasmic reticulum (ER) serves as a central hub for protein production and sorting in eukaryotic cells, processing approximately one-third of the cellular proteome. Protein targeting to the ER occurs through multiple pathways that operate both during and independent of translation. The classical translation-dependent pathway, mediated by cytosolic factors like signal recognition particle, recognizes signal peptides or transmembrane helices in nascent proteins, while translation-independent mechanisms utilize RNA-based targeting through specific sequence elements and RNA-binding proteins. At the core of these processes lies the Sec61 complex, which undergoes dynamic conformational changes and coordinates with numerous accessory factors to facilitate protein translocation and membrane insertion across and into the endoplasmic reticulum membrane. This review focuses on the molecular mechanisms of protein targeting to the ER, from the initial recognition of targeting signals to the dynamics of the translocation machinery, highlighting recent discoveries that have revealed unprecedented complexity in these cellular trafficking pathways.

Biophysical reviews (ISSUE 2 2025): LAFeBS, alive, kicking, and growing: the story continues

This Editorial for Volume 17 Issue 2 of Biophysical Reviews introduces the contents of the second Special Issue on the Latin American Federation of Biophysical Societies (LAFeBS). Biophysical Reviews is the official journal of the International Union for Pure and Applied Biophysics (IUPAB). The multidisciplinary scope of the articles in this issue reflects LAFeBS's commitment to highlighting regional contributions to the advancement of biophysics across all its branches.