Ku70: The DNA's Mr. Fix-it

Ku70, known by several synonyms including X-ray repair cross-complementing, 5'-deoxyribose-5-phosphate lyase Ku70 protein 6, 70 kDa subunit of Ku antigen, XRCC6, and G22P1, is a 70 kDa protein that was shown to be involved in multiple cellular pathways, mainly involving DNA repair and recombination (2). Ku70 functions as a single-stranded DNA-dependent ATP-dependent helicase in the Ku70/Ku80 complex. Ku70 plays a role in non-homologous end joining (NHEJ) required for double-strand DNA break repair and V(D)J recombination. Ku70 has also been found to participate in complex DNA strand breaks in association with Ku80, XRCC4/Ligase IV/XLF, and DNA-PKcs (3). The Ku70 protein is induced in cells exposed to various radiation including ultra-soft X-rays (USX), multi-photon near infrared (NIR) laser irradiation, X-rays, gamma-rays, and ultraviolet (UV) radiation (1, 3).

Immunohistochemistry-Paraffin: Ku70 Antibody

In recent studies, the use of UVA and Terahertz radiation (THz), delivered in pulses, has been used to activate DNA damage response in human skin tissue. Terahertz (THz) radiation is a type of radiation that falls between microwaves and infrared light (4). Researchers are using this form of radiation therapy to induce DNA repair mechanisms for use in medical diagnostics, security, and cancer research (4). THz pulses are able to penetrate to a sub-mm depth, making this type of treatment most promising in patients with skin cancers (1). There is also evidence that the THz radiation causes upregulation of four cyclin-dependent kinase inhibitor protein family members: p21, p16, p15 and p27. These proteins are key cell cycle regulator proteins and act as tumor suppressors. Their upregulation provides cells crucial time for repairing DNA (1). Further study is required to elaborate the specific roles of p21, p16, p15, p27 and Ku70 proteins in cellular response to THz pulse exposure (1).