title: Krüppel-like factor 2 represses transcription of the telomerase catalytic subunit human telomerase reverse transcriptase (hTERT) in human T cells.
abstract: In normal human T cells, telomerase activity is strictly regulated. T cells are thought to express telomerase to avoid replicative senescence, unlike most normal somatic cells with definite replicative lifespan. T cells in blood and tissues are usually in a state of quiescence without expression of the limiting catalytic subunit of telomerase, human telomerase reverse transcriptase (hTERT). In contrast to activation, repression of hTERT transcription has not been studied well. Our previous studies have found an hTERT promoter element with repressive function. Here we identified KLF2, which represses hTERT transcription by binding to the putative promoter element. KLF2 and hTERT exhibited reciprocal mRNA expression patterns in primary human T cells. In activated T cells, KLF2 binding to the hTERT promoter was eliminated, relieving the repression of hTERT transcription found in resting T cells. Our results suggest that KLF2 is involved in strict repression of hTERT expression through binding to the promoter in primary human T cells.
authors.affiliation: From the Human Gene Sciences Center, Tokyo Medical and Dental University, Tokyo 113-8510 and the Division of Virology, Niigata University Graduate School of Medicine and Dental Sciences, Niigata 951-8510, Japan.
authors.forename: Toshifumi
authors.initials: T
authors.lastname: Hara
authors.affiliation: From the Human Gene Sciences Center, Tokyo Medical and Dental University, Tokyo 113-8510 and.
authors.forename: Mariko
authors.initials: M
authors.lastname: Mizuguchi
authors.affiliation: the Division of Virology, Niigata University Graduate School of Medicine and Dental Sciences, Niigata 951-8510, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Fujii
authors.affiliation: From the Human Gene Sciences Center, Tokyo Medical and Dental University, Tokyo 113-8510 and naka.gene@tmd.ac.jp.
authors.forename: Masataka
authors.initials: M
authors.lastname: Nakamura
mesh_terms: D001483:Base Sequence; D015153:Blotting, Western; D020134:Catalytic Domain; D002478:Cells, Cultured; D017931:DNA Primers; D024202:Electrophoretic Mobility Shift Assay; D006801:Humans; D051741:Kruppel-Like Transcription Factors / Q000235:genetics / Q000502:physiology*; D016133:Polymerase Chain Reaction; D034741:RNA, Small Interfering / Q000235:genetics; D013601:T-Lymphocytes / Q000201:enzymology*; D019098:Telomerase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic / Q000502:physiology*
chemical_list: D017931:DNA Primers; C096161:KLF2 protein, human; D051741:Kruppel-Like Transcription Factors; D034741:RNA, Small Interfering; C509186:TERT protein, human; D019098:Telomerase
keywords: Krüppel-like Factor 2 (KLF2); T-cells; Telomerase Reverse Transcriptase (TERT); Transcription; Transcription Repressor; Zinc Finger