FAM111B antibody is a research tool used to study the FAM111B protein, encoded by the FAM111B gene located on human chromosome 11q12.1. FAM111B is a nuclear protein implicated in DNA repair, cell proliferation, and apoptosis regulation. Its functional roles remain incompletely understood, but studies suggest interactions with proliferating cell nuclear antigen (PCNA) and potential involvement in proteasome-mediated degradation pathways. Mutations in FAM111B are linked to hereditary fibrosing poikiloderma (HNFJ), a rare autosomal dominant disorder characterized by skin abnormalities, fibrosis, and increased cancer risk. Dysregulated FAM111B expression has also been observed in cancers, including pancreatic, hepatocellular, and cervical carcinomas, where overexpression correlates with poor prognosis.
FAM111B antibodies are primarily used in Western blotting, immunohistochemistry, and immunofluorescence to detect protein expression patterns, subcellular localization, and disease-associated alterations. Structural studies predict FAM111B contains a trypsin-like protease domain and a nuclear localization signal, though its enzymatic activity remains unconfirmed. Pathogenic HNFJ-associated mutations (e.g., p.Ser342Ala) may disrupt DNA repair mechanisms, contributing to genomic instability. Research continues to explore FAM111B's molecular interactions, its role in cancer progression, and its potential as a diagnostic or therapeutic target. Commercial antibodies vary in specificity, requiring validation via knockout controls to ensure reliability in experimental models.