title: Dynamic changes in subcellular localization of cattle XLF during cell cycle, and focus formation of cattle XLF at DNA damage sites immediately after irradiation.
abstract: Clinically, many chemotherapeutics and ionizing radiation (IR) have been applied for the treatment of various types of human and animal malignancies. These treatments kill tumor cells by causing DNA double-strand breaks (DSBs). Core factors of classical nonhomologous DNA-end joining (C-NHEJ) play a vital role in DSB repair. Thus, it is indispensable to clarify the mechanisms of C-NHEJ in order to develop next-generation chemotherapeutics for cancer. The XRCC4-like factor (XLF; also called Cernunnos or NHEJ1) is the lastly identified core NHEJ factor. The localization of core NHEJ factors might play a critical role in regulating NHEJ activity. The localization and function of XLF have not been elucidated in animal species other than mice and humans. Domestic cattle (Bos taurus) are the most common and vital domestic animals in many countries. Here, we show that the localization of cattle XLF changes dynamically during the cell cycle. Furthermore, EYFP-cattle XLF accumulates quickly at microirradiated sites and colocalizes with the DSB marker γH2AX. Moreover, nuclear localization and accumulation of cattle XLF at DSB sites are dependent on 12 amino acids (288-299) of the C-terminal region of XLF (XLF CTR). Furthermore, basic amino acids on the XLF CTR are highly conserved among domestic animals including cattle, goat and horses, suggesting that the CTR is essential for the function of XLF in domestic animals. These findings might be useful to develop the molecular-targeting therapeutic drug taking XLF as a target molecule for human and domestic animals.
authors.affiliation: Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan.
authors.forename: Manabu
authors.initials: M
authors.lastname: Koike
authors.forename: Yasutomo
authors.initials: Y
authors.lastname: Yutoku
authors.forename: Aki
authors.initials: A
authors.lastname: Koike
mesh_terms: D000818:Animals; D002417:Cattle; D002453:Cell Cycle / Q000502:physiology / Q000528:radiation effects; D002460:Cell Line; D002467:Cell Nucleus / Q000201:enzymology / Q000528:radiation effects; D004249:DNA Damage / Q000528:radiation effects*; D059766:DNA End-Joining Repair / Q000528:radiation effects*; D045643:DNA Repair Enzymes / Q000378:metabolism* / Q000528:radiation effects; D005455:Fluorescent Antibody Technique / Q000662:veterinary; D015151:Immunoblotting / Q000662:veterinary; D013347:Subcellular Fractions / Q000201:enzymology* / Q000528:radiation effects
chemical_list: D045643:DNA Repair Enzymes