Isoform 5 of Cell adhesion molecule 1

Cell adhesion molecule 1 (CADM1) is a cell surface glycoprotein that mediates cell-to-cell adhesion and membrane fusion events. The protein is notable for its role in neuron-virus interactions, particularly in facilitating measles virus entry and transsynaptic transmission through interaction with viral hemagglutinin and F-protein-mediated membrane fusion (UniProt: Q9BY67-5).

CADM1 is expressed in nervous tissue and functions at synaptic and neuronal interfaces. While no inherited disease associations are documented in UniProt, the protein's involvement in cell adhesion and synaptic function suggests relevance to neurobiological processes.

In Alzheimer's disease, isoform 5 of CADM1 is downregulated in post-mortem AD brain tissue compared to age-matched controls (mean log2 fold-change: −0.36; Chaparral AD proteomics). This downregulation was detected across subcellular fractions in a TMT-labeled quantitative proteomics study of human post-mortem brain homogenates, suggesting reduced synaptic cell adhesion capacity may contribute to neurodegeneration in AD.