title: Transcription Regulation of the Human Telomerase Reverse Transcriptase (hTERT) Gene.
abstract: Embryonic stem cells and induced pluripotent stem cells have the ability to maintain their telomere length via expression of an enzymatic complex called telomerase. Similarly, more than 85%-90% of cancer cells are found to upregulate the expression of telomerase, conferring them with the potential to proliferate indefinitely. Telomerase Reverse Transcriptase (TERT), the catalytic subunit of telomerase holoenzyme, is the rate-limiting factor in reconstituting telomerase activity in vivo. To date, the expression and function of the human Telomerase Reverse Transcriptase (hTERT) gene are known to be regulated at various molecular levels (including genetic, mRNA, protein and subcellular localization) by a number of diverse factors. Among these means of regulation, transcription modulation is the most important, as evident in its tight regulation in cancer cell survival as well as pluripotent stem cell maintenance and differentiation. Here, we discuss how hTERT gene transcription is regulated, mainly focusing on the contribution of trans-acting factors such as transcription factors and epigenetic modifiers, as well as genetic alterations in hTERT proximal promoter.
authors.affiliation: Cancer and Stem Cell Biology Program, Duke-NUS Graduate Medical School, Singapore 169857, Singapore. khairul@u.duke.nus.edu.
authors.forename: Muhammad Khairul
authors.initials: MK
authors.lastname: Ramlee
authors.affiliation: Cancer and Stem Cell Biology Program, Duke-NUS Graduate Medical School, Singapore 169857, Singapore. wang.jing@u.duke.nus.edu.
authors.forename: Jing
authors.initials: J
authors.lastname: Wang
authors.affiliation: Cancer and Stem Cell Biology Program, Duke-NUS Graduate Medical School, Singapore 169857, Singapore. wei.xun@u.duke.nus.edu.
authors.forename: Wei Xun
authors.initials: WX
authors.lastname: Toh
authors.affiliation: Cancer and Stem Cell Biology Program, Duke-NUS Graduate Medical School, Singapore 169857, Singapore. shang.li@duke-nus.edu.sg.|Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117597, Singapore. shang.li@duke-nus.edu.sg.
authors.forename: Shang
authors.initials: S
authors.lastname: Li
keywords: mutation; promoter; telomerase; telomere; transcription regulation