Lamina-associated polypeptide 2, isoform alpha

Lamina-associated polypeptide 2, isoform alpha (LAP2α), encoded by TMPO, is a nuclear structural protein with a molecular weight of ~75 kDa (UniProt: P42166). It functions in nuclear organization and post-mitotic nuclear assembly, where it cooperates with LMNA in anchoring the retinoblastoma protein RB1 to the nuclear lamina. Certain isoforms may also contribute to T-cell development and immune regulation.

LAP2α is primarily localized to the nuclear envelope and nucleoplasm, reflecting its role in nuclear architecture and protein-DNA interactions. The UniProt record lists no explicit disease associations for this protein.

In Alzheimer's Disease, LAP2α is significantly upregulated in post-mortem AD brain tissue compared to age-matched controls, with a mean log2 fold-change of 0.71 (Chaparral AD proteomics). This elevation was detected across subcellular fractions in a TMT-labeled, data-dependent proteomics study of human post-mortem AD brain. The upregulation suggests a potential compensatory or pathological involvement of nuclear structural remodeling in AD neurodegeneration.