title: 5-Ethynyl-2'-deoxycytidine as a new agent for DNA labeling: detection of proliferating cells.
abstract: The labeling of newly synthesized DNA in cells to identify cell proliferation is an important experimental technique. The most accurate methods incorporate [(3)H]thymidine or 5-bromo-2'-deoxyruidine (BrdU) into dividing cells during S phase, which is subsequently detected by autoradiography or immunohistochemistry, directly measuring the newly synthesized DNA. Recently, a novel method was developed to detect DNA synthesis in proliferating cells based on a novel thymidine analog, 5-ethynyl-2'-deoxyuridine (EdU). EdU is incorporated into DNA and subsequently detected with a fluorescent azide via "click" chemistry. This novel technique is highly sensitive and does not require DNA denaturation. However, it was also found that EdU exhibits time-dependent inhibition effects on cell growth. Therefore, here we report a novel deoxycytidine analog, 5-ethynyl-2'-deoxycytidine (EdC), that can be used to detect DNA synthesis in vitro and in vivo at a similar sensitivity level compared with EdU. Furthermore, the EdC-induced cytotoxicity is much less than that of EdU when combined with thymidine. This will be a potential application for the long-term detection of proliferating cells.
authors.affiliation: Laboratory of RNA Chemical Biology, Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530, China.
authors.forename: Dezhong
authors.initials: D
authors.lastname: Qu
authors.forename: Guoxing
authors.initials: G
authors.lastname: Wang
authors.forename: Zhe
authors.initials: Z
authors.lastname: Wang
authors.forename: Li
authors.initials: L
authors.lastname: Zhou
authors.forename: Weilin
authors.initials: W
authors.lastname: Chi
authors.forename: Shujie
authors.initials: S
authors.lastname: Cong
authors.forename: Xiaoshuai
authors.initials: X
authors.lastname: Ren
authors.forename: Peizhou
authors.initials: P
authors.lastname: Liang
authors.forename: Biliang
authors.initials: B
authors.lastname: Zhang
mesh_terms: D000818:Animals; D016923:Cell Death / Q000187:drug effects; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D004247:DNA / Q000096:biosynthesis / Q000378:metabolism*; D003857:Deoxyuridine / Q000031:analogs & derivatives* / Q000737:chemistry / Q000378:metabolism / Q000633:toxicity; D005434:Flow Cytometry; D006801:Humans; D051379:Mice; D009928:Organ Specificity / Q000187:drug effects; D013194:Staining and Labeling / Q000379:methods*; D013936:Thymidine / Q000378:metabolism; D013997:Time Factors
chemical_list: D004247:DNA; C031086:5-ethynyl-2'-deoxyuridine; D013936:Thymidine; D003857:Deoxyuridine