Telomerase reverse transcriptase

Zhang Z et al. (2006). Delivery of telomerase reverse transcriptase small interfering RNA in complex with positively charged single-walled carbon nanotubes suppresses tumor growth. Clin. Cancer Res. 12(16) 4933 1939. 

Beyond the Hayflick limit, cells that have escaped senescence and/or crisis must progress beyond mortality stage 2 (Figure 26.1). Recent studies have shown that human telomerase reverse transcriptase cDNA (hTERT) in combination with viral oncogenes also has the potential to immortalize human airway epithelial cells [15, 78-82], However, even though hTERT alone will cause enhanced growth potential of a cell line, with the exception of one study [81],... 

Greenberg, R. A., R. C. Allsopp, L. Chin, G. B. Morin, and R. A. DePinho. 1998. Expression of mouse telomerase reverse transcriptase during development, differentiation and proliferation. Oncogene 16(13) 1723-30. 

Ge Z, Liu C, Bjorkholm M, Gruber A, Xu D (2006) Mitogen-activated protein kinase cascade-mediated histone H3 phosphorylation is critical for telomerase reverse transcriptase expression/telomerase activation induced by proliferation. Mol Cell Biol 26(l) 230-237 Giet R, Glover DM (2001) Drosophila aurora B kinase is required for histone H3 phosphorylation and condensin recruitment during chromosome condensation and to organize the central spindle during cytokinesis. J Cell Biol 152(4) 669-682... 

Telomerase is an enzyme in eukaryotes used to maintain the telomeres. It contains a short RNA template complementary to the DNA telomere sequence, as well as telomerase reverse transcriptase activity (hTRT). Telomerase is thus able to replace telomere sequences that would otherwise be lost during replication. Normally telomerase activity is present only in embryonic cells, germ (reproductive) cells, and stem cells, but not in somatic cells. 

B. Minev, J. Hipp, H. Firat, J.D. Schmidt, P. Langlade-Demoyen, and M. Zanetti, C 4otoxic T cell immunity against telomerase reverse transcriptase in humans, Proc. Natl. Acad. Sci. USA 97, 4796 4801(2000). 

F. Bachand and C. Autexier. 2001. Functional regions of human telomerase reverse transcriptase and human telomerase RNA required for telomerase activity and RNA-protein interactions Mo/. Cell Biol. 21 1888-1897. (PuhMed) (Full Text in PMC)... 

Hong HX, Zhang YM, Xu H, Su ZY, and Sun P. Immortalization of swine umbilical vein endothelial cells with human telomerase reverse transcriptase. Mol Cells 24 358-363,2007. 

Kang SS, Kwon T, Kwon DY, Do SI. 1999. Akt protein kinase enhances human telomerase activity through phosphorylation of telomerase reverse transcriptase subunit. J. Biol. Chem. 274 13085-90... 

Kyo S, Takakura M, Taira T, Kanaya T, Itoh H, et al. 2000. Spl cooperates with c-Myc to activate transcription of the human telomerase reverse transcriptase gene (hTERT). Nucleic Acids Res. 28 669-77... 

Greenberg RA, O Hagan RC, Deng H, Xiao Q, Hann SR, et al. 1999. Telomerase reverse transcriptase gene is a direct target of c-Myc but is not functionally equivalent in cellular transformation. Oncogene 18 1219-26... 

Dasi F, Lledo S, Garcia-Granero E, RipoU R, Marugan M, Tormo M, et al. Real-time quantification in plasma of human telomerase reverse transcriptase (hTERT) mRNA a simple blood test to monitor disease in cancer patients. Lab Invest 2001 81 767-9. 

As often happens in these days of the human genome project, the human version hTERT) was found shortly thereafter [16, 17]. It was expressed in a variety of transformed cells but not detectable in primary cultures of human somatic cells, already giving a simple answer as to why telomerase activity was deficient in somatic cells. Thus, over a short time span, we went from having no telomerase protein to a whole family of TERTs (Telomerase Reverse Transcriptases). 

Telomerase RNA bound by protein motifs specific to telomerase reverse transcriptase. Mol. Cell 6, 493-499. 

Friedman, K.L., Heit, J.J., Long, D. L, and Cech, T. R. (2003). N-terminal domain of yeast telomerase reverse transcriptase recruitment of Est3p to the telomerase complex. Mol. Biol. Cell 14, 1-13. 

Mitchell, J.R., and Collins, K. (2000) Human telomerase activation requires two independent interactions between telomerase RNA and telomerase reverse transcriptase in vivo and in vitro. Mol. Cell 6, 361-371. 

Trott, D.A., Newbold, R.F., and Nabholz, M. (2003). A chromosome 3-encoded repressor of the human telomerase reverse transcriptase (hTERT) gene controls the state ofhTERT chromatin. Gancer Res. 63, 689-695. 

Rufer, N., Migliaccio, M., Antonchuk, J., Humphries, R. K., Roosnek, E., and Lansdorp, P.M. (2001). Transfer of the human telomerase reverse transcriptase (TERT) gene into T lymphocytes results in extension of replicative potential. Blood 98, 597-603. 

Huo LF, Tang JW, Huang JJ, Huang PT, Huang CF, Kung HF, Lin MC. Cancer immunotherapy targeting the telomerase reverse transcriptase. Cell Mol Immunol 2006 3 1-11. 

Wooten-Blanks, L.G., Song, P., Senkal, C.E., and Ogretmen, B. Mechanisms of ceramide-mediated repression of the human telomerase reverse transcriptase promoter via deacetylation of Sp3 by histone deacetylase 1. Faseb J, 21, 2007, 3386-3397. 

Wooten, L.G. and Ogretmen, B. Spl/Sp3-dependent regulation of human telomerase reverse transcriptase promoter activity by the bioactive sphingolipid ceramide. J Biol Chem, 280, 2005, 28867-28876. 

The usefulness of genetic modification of cells which are to be used in engineering tissue is evidenced by non-mahgnant transformation with human telomerase reverse transcriptase of adrenocortic bovine ceUs. ... 

Retroviral-mediated transduction of liTERT (human telomerase reverse transcriptase) in human dermal microvascular endothelial cells (EC) (HDMEC) results in cell hues that form microvasculai stractures upon subcutaneous implantation in severe combined immunodeficiency mice (SCID) mice. Anti-human type IV collagen basement membrane immu-noreactivity and visualization of enhanced green fluorescent protein (eGEP)-labeled microvessels confiimed the human origin of these vessels. Piimaiy HDMEC-derived vessel density decreased with time, while telomerized HDMEC maintained durable vessels six... 

Michael Thomas, Lianqing Yang and Peter J. Hornsby, Formation of functional tissue from transplanted adrenocortical cells expressing telomerase reverse transcriptase. Nature Biotechnology, 18 (2000), 39 2. 

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