Purity: > 90% by SDS - PAGE Format: Liquid. In 20mM Tris-HCl buffer (pH 8.0) containing 0.1M NaCl, 20% glycerol,1mM DTT. Non-homologous end-joining factor 1, also known as NHEJ1, belongs to the XLF family. NHEJ1 was originally discovered as the protein mutated in five patients with growth retardation, microcephaly, and immunodeficiency. The protein is required for the non-homologous end joining (NHEJ) pathway of DNA repair. Patients with NHEJ1 mutations also have immunodeficiency due to a defect in V(D)J recombination, which utilizes NHEJ to promote immune system diversity. XLF interacts with DNA ligase IV and XRCC4 and is thought to be involved in the ligation step of NHEJ. Recombinant human NHEJ1 protein, fused to His-tag at N-terminus, was expressed in E.coli and purified by using conventional chromatography techniques.