PDZ domain-containing protein 4

PDZD4 (PDZ domain-containing protein 4) is a 769-amino acid protein encoded by the PDZD4 gene in humans (UniProt: Q76G19). PDZ domains typically facilitate protein–protein interactions and cellular localization; this protein likely serves scaffolding or signaling roles, though specific molecular functions are not detailed in available UniProt records.

The protein's tissue distribution and pathway context remain undocumented in the UniProt entry. No disease associations are annotated in UniProt's curated disease field.

PDZD4 is associated with Alzheimer's Disease according to Chaparral curation tags. In human post-mortem AD brain tissue compared to age-matched controls (TMT-labeled proteomics across four subcellular fractions: P2, P3, S2, S3), PDZD4 was significantly down-regulated with a mean log2 fold-change of −0.56 (Chaparral AD proteomics). This reduction suggests a possible loss of PDZD4-dependent scaffolding or signaling in AD pathology, though the functional consequence remains to be elucidated.