PAX-interacting protein 1 (PAXIP1)

PAX-interacting protein 1 (PAXIP1) is a nuclear protein characterized by six BRCT domains and encoded by the PAXIP1 gene. It is crucial for the maintenance of genome stability, chromatin condensation, and proper progression through mitosis[1][3]. PAXIP1 acts as a cofactor in histone H3 lysine 4 trimethylation via association with the MLL3/4 methyltransferase complexes and links these chromatin-modifying enzymes to gene promoters through direct or indirect interaction with DNA-bound transcription factors, such as members of the paired box (PAX) family[2][3][4][6]. PAXIP1 is involved in DNA double-strand break repair, functioning in both DNA damage signaling and homologous recombination repair pathways, and is required for effective post-irradiation cell survival[3][4]. In lymphocytes, PAXIP1 specifically regulates RAG-mediated chromatin remodeling, cleavage and repair during V(D)J recombination essential for T cell development and immunoglobulin class switching[2]. Loss of PAXIP1 impacts the transcriptional activation of immune-related genes such as sphingosine-1-phosphate receptor 1 (S1PR1), impinging on mature T cell egress from the thymus[2]. PAXIP1 is also implicated as a disease gene in neurodevelopmental and neurodegenerative disorders, including roles in Alzheimer's disease and rare genetic syndromes[1][3]. No known drugs directly target PAXIP1, and it is not currently considered a direct therapeutic target or biomarker[3].

Other names

PAXIP1PTIPTNRC2PAXIP1LCAGF28CAGF29PACIP1PAX transcription activation domain-interacting protein 1PAX transactivation activation domain-interacting proteinPAX interacting (with transcription-activation domain) protein 1