Paraneoplastic Antigen Ma2 (PNMA2)

Paraneoplastic antigen Ma2 (PNMA2) is a 364-amino acid protein encoded by the PNMA2 gene in humans (UniProt: Q9UL42). The protein belongs to the paraneoplastic antigen family and is recognized as an autoantigen in paraneoplastic neurological syndromes, though its specific molecular function remains incompletely characterized in UniProt.

PNMA2 is expressed in nervous tissue and has been associated with cancer-related neurological complications. No tissue-specific pathway annotations are currently available in UniProt for this protein.

PNMA2 shows reduced expression in Alzheimer's disease brain tissue. According to Chaparral AD proteomics analysis of post-mortem AD brain versus age-matched controls using TMT-labeled quantitative proteomics across four subcellular fractions, PNMA2 is downregulated with a mean log2 fold-change of −0.34 (Chaparral AD proteomics). The biological significance of this modest reduction in AD pathology remains to be determined.