Dynein axonemal assembly factor 5 (DNAAF5)

Dynein axonemal assembly factor 5 (DNAAF5), previously known as HEATR2, is a cytoplasmic protein essential for the preassembly and stability of axonemal dynein arms, which are large multisubunit motor protein complexes attached to microtubules within the ciliary axoneme[1][3][4]. DNAAF5 contains characteristic HEAT repeats (α-helical domains) and acts as a scaffold or chaperone, facilitating the assembly of both inner (IDA) and outer (ODA) axonemal dynein arms before their transport into motile cilia[2][4]. Mutations in DNAAF5 disrupt this preassembly pathway, resulting in the absence or dysfunction of dynein arms within the cilium and leading to the genetic disorder primary ciliary dyskinesia (PCD), which is characterized by impaired mucociliary clearance, recurrent respiratory infections, and, in severe cases, laterality defects and hydrocephalus[1][2][3][4]. DNAAF5 is expressed only in cells with motile cilia and is not found in the assembled cilium; its critical role is restricted to the cytoplasmic phase of dynein arm complex maturation[2][4]. There are no current drugs targeting DNAAF5, and the molecular mechanisms are relevant primarily for genetic diagnosis and research into ciliopathies.

Other names

HEATR2CILD18HEAT repeat-containing protein 2HEAT repeat containing 2dynein assembly factor 5, axonemalFLJ20397FLJ31671FLJ39381FLJ25564

Not applicable (no drugs currently target DNAAF5 directly)