PACRG (parkin coregulated) is a 30 kDa protein that functions in two distinct cellular contexts. In cilia and flagella, PACRG localizes to the inner junction of doublet microtubules within the axoneme, where it binds the adaptor protein MEIG1 and directly interacts with tubulin to regulate axonemal assembly and enable motile cilia beating 1 2. In the context of Parkinson's disease, PACRG suppresses cell death triggered by accumulation of the parkin substrate Pael receptor (Pael-R) by forming molecular chaperone complexes with heat shock proteins 70 and 90 3. When the proteasome is inhibited, PACRG facilitates inclusion body formation containing Pael-R and chaperone machinery, and the protein itself becomes a component of Lewy bodies, suggesting a protective role for dopaminergic neurons 3 4. Beyond neurodegeneration, PACRG promotes nuclear factor κB (NF-κB) activation in response to tumor necrosis factor signaling by functionally replacing the adaptor protein SHARPIN within the linear ubiquitin chain assembly complex, indicating roles in inflammatory and immune responses 5. PACRG polymorphisms show associations with hyperlipidemia in the Chinese Maonan minority 6 and abnormal promoter methylation in acute lymphoblastic leukemia and chr6 myeloid leukemia 7, though specific therapeutic interventions targeting PACRG remain undeveloped.