IgLON family member 5

IGLON5 (IgLON family member 5) is a 336-amino-acid immunoglobulin superfamily protein encoded by the IGLON5 gene (UniProt: A6NGN9). Members of the IgLON family are cell adhesion molecules implicated in neuronal development and synaptic organization, though specific molecular function details for IGLON5 are not extensively annotated in available databases.

IGLON5 is expressed in neural tissues and belongs to a protein family with established roles in neuronal connectivity. No curated disease associations are listed in the UniProt record itself; however, the protein has been identified in Alzheimer's disease proteomics studies (Chaparral AD proteomics).

In Alzheimer's disease brain tissue, IGLON5 is significantly downregulated compared to age-matched controls, with a mean log2 fold-change of −0.897 (Chaparral AD proteomics). This reduction was observed in human post-mortem AD brain tissue analyzed via TMT-labeled mass spectrometry across subcellular fractions. The downregulation of IgLON family proteins in AD may reflect compromised neuronal adhesion and synaptic integrity characteristic of neurodegeneration.