Endoplasmic reticulum and Golgi apparatus (ER/Golgi)

The endoplasmic reticulum (ER) and Golgi apparatus are essential organelles that form the core of the endomembrane system in eukaryotic cells. The ER is responsible for the synthesis of lipids and the folding and assembly of proteins destined for the cell surface or secretion (StatPearls, 2023). It also acts as a critical calcium storage site, regulating intracellular signaling and homeostasis. The Golgi apparatus functions as a processing and sorting hub, where proteins undergo post-translational modifications such as glycosylation before being packaged into vesicles (Molecular Biology of the Cell, 2014). Disruption of these processes leads to ER stress, which triggers the Unfolded Protein Response (UPR), a pathway linked to the pathogenesis of neurodegenerative diseases, cancer, and metabolic disorders (Nature Reviews Molecular Cell Biology, 2018). Pharmacological agents like Thapsigargin and Brefeldin A are used in research to disrupt these organelles by inhibiting calcium pumps or vesicle transport, respectively (PubChem). In clinical practice, drugs like Bortezomib indirectly target ER homeostasis by inhibiting the proteasome, leading to a lethal accumulation of misfolded proteins in cancer cells (PubMed, 2017). However, because these organelles are fundamental to the survival of all eukaryotic cells, they are generally classified as cellular compartments rather than specific molecular targets.

Other names

Endomembrane systemSecretory pathwayER-Golgi networkER-Golgi intermediate compartment

Drugs affecting these organelles typically work by inhibiting the Sarco/endoplasmic reticulum Ca2+-ATPase (SERCA), disrupting vesicle-mediated transport between the ER and Golgi, or inducing the Unfolded Protein Response (UPR) through the accumulation of misfolded proteins.