Dynactin subunit 4

Dynactin subunit 4 (DCTN4, also called Dyn4) is a 460-amino acid protein that forms part of the dynactin complex, a regulatory factor essential for activating the molecular motor dynein and enabling its highly processive transport along microtubules (UniProt: Q9UJW0). This function is critical for intracellular cargo delivery and cytoplasmic organization in neurons and other cell types.

Dynactin subunit 4 participates in dynein-mediated axonal transport, a process central to neuronal homeostasis and function. No disease associations are documented in the UniProt record for this protein.

In Alzheimer's Disease, dynactin subunit 4 shows reduced abundance in post-mortem human brain tissue compared to age-matched controls (Chaparral AD proteomics). The protein was downregulated with a mean log2 fold-change of −0.70 across analyzed subcellular fractions in TMT-labeled mass spectrometry analysis. This downregulation suggests compromised dynein-mediated transport capacity, which may contribute to the axonal transport deficits and neurodegeneration characteristic of AD pathology.