title: Characterization of the intramolecular G-quadruplex promoting activity of Est1.
abstract: In the budding yeast Saccharomyces cerevisiae, telomeric DNA includes TG1-3/C1-3A double-stranded DNA and a protruding G-rich overhang. Our previous studies revealed that the telomerase regulatory subunit Est1 promotes telomeric single-stranded DNA to form intermolecular G-quadruplex in vitro, and this activity is required for telomere replication and protection in vivo. In this study, we further characterized the G-quadruplex promoting activity of Est1. Here we report that Est1 is able to promote the single-stranded oligonucleotide of (TGTGTGGG)4, which mimics the natural telomeric DNA, to form intramolecular G-quadruplex. Therefore, it remains possible that the intramolecular G-quadruplex promoting activity of Est1 is biologically relevant in telomere replication in vivo.
authors: The State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China.
authors: Qian-Jin
authors: QJ
authors: Li
authors: Xia-Jing
authors: XJ
authors: Tong
authors: Yi-Min
authors: YM
authors: Duan
authors: Jin-Qiu
authors: JQ
authors: Zhou
mesh_terms: D002942:Circular Dichroism; D004261:DNA Replication; D004277:DNA, Single-Stranded / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D054856:G-Quadruplexes; D009841:Oligonucleotides / Q000138:chemical synthesis / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000737:chemistry* / Q000201:enzymology / Q000235:genetics; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D019098:Telomerase / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D016615:Telomere / Q000201:enzymology / Q000235:genetics
chemical_list: D004277:DNA, Single-Stranded; D009841:Oligonucleotides; D029701:Saccharomyces cerevisiae Proteins; C099024:EST1 protein, S cerevisiae; D019098:Telomerase