Nucleic Acids Research, 2000, Vol. 28, No. 13 2605-2612
© 2000 Oxford University Press
A novel functional genomics approach identifies mTERT as a suppressor of fibroblast transformation
Immusol Inc., 3050 Science Park Road, San Diego, CA 92121, USA and 1Department of Medicine, University of California, San Diego, CA 92121, USA
As a tool for functional genomics, a hairpin ribozyme gene library with randomized target recognition sequences was constructed in a retroviral vector. This library has the potential to target and cleave any possible RNA substrate. Mouse fibroblasts transduced with this ribozyme gene vector library were selected in a focus formation assay to isolate in vivo functional ribozymes that promote cell transformation in tissue culture. After two successive rounds of selection by focus formation assay, a transforming ribozyme (Rz007) was identified. The sequence of this ribozyme was used to identify the putative target genes responsible for the transformation. A candidate gene target for Rz007 encodes telomerase reverse transcriptase (mTERT). Both mRNA level and enzymatic activity of mTERT were down-regulated in Rz007-transformed cells. Furthermore, newly designed ribozymes, recognizing other potential ribozyme cleavage sites unique to the mTERT mRNA, also cause cell transformation, thus validating the role of mTERT in suppressing the transformation phenotype. These surprising results suggest that the commonly accepted role of telomerase in maintaining cellular immortalization is more complicated than previously thought. These studies also demonstrate the utility of this novel ‘reverse’ functional genomics approach, enabling the targeted discovery of genes, whether previously known or not, that are involved in any selectable phenotype.
* To whom correspondence should be addressed. Tel: +1 858 677 0182; Fax: +1 858 677 0587; Email: barber@immusol.com
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  B. de Chassey, I. Mikaelian, A.-L. Mathieu, M. Bickle, D. Olivier, D. Negre, F.-L. Cosset, B. B. Rudkin, and P. Colas An Antiproliferative Genetic Screening Identifies a Peptide Aptamer That Targets Calcineurin and Up-regulates Its Activity Mol. Cell. Proteomics, March 1, 2007; 6(3): 451 - 459. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. A. SEYHAN, A. V. VLASSOV, H. ILVES, L. EGRY, R. L. KASPAR, S. A. KAZAKOV, and B. H. JOHNSTON Complete, gene-specific siRNA libraries: Production and expression in mammalian cells RNA, May 1, 2005; 11(5): 837 - 846. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. Waninger, K. Kuhen, X. Hu, J. E. Chatterton, F. Wong-Staal, and H. Tang Identification of Cellular Cofactors for Human Immunodeficiency Virus Replication via a Ribozyme-Based Genomics Approach J. Virol., December 1, 2004; 78(23): 12829 - 12837. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 E. Suyama, R. Wadhwa, K. Kaur, M. Miyagishi, S. C. Kaul, H. Kawasaki, and K. Taira Identification of Metastasis-related Genes in a Mouse Model Using a Library of Randomized Ribozymes J. Biol. Chem., September 10, 2004; 279(37): 38083 - 38086. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. C. Deocaris, S. C. Kaul, K. Taira, and R. Wadhwa Emerging Technologies: Trendy RNA Tools for Aging Research J. Gerontol. A Biol. Sci. Med. Sci., August 1, 2004; 59(8): B771 - B783. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. Shiota, M. Sano, M. Miyagishi, and K. Taira Ribozymes: Applications to Functional Analysis and Gene Discovery J. Biochem., August 1, 2004; 136(2): 133 - 147. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 H. Kawasaki and K. Taira A functional gene discovery in the Fas-mediated pathway to apoptosis by analysis of transiently expressed randomized hybrid-ribozyme libraries Nucleic Acids Res., August 15, 2002; 30(16): 3609 - 3614. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J.-L. Mergny, J.-F. Riou, P. Mailliet, M.-P. Teulade-Fichou, and E. Gilson Natural and pharmacological regulation of telomerase Nucleic Acids Res., February 15, 2002; 30(4): 839 - 865. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. Kruger, C. Beger, P. J. Welch, J. R. Barber, M. P. Manns, and F. Wong-Staal Involvement of Proteasome alpha -Subunit PSMA7 in Hepatitis C Virus Internal Ribosome Entry Site-Mediated Translation Mol. Cell. Biol., December 15, 2001; 21(24): 8357 - 8364. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Kruger, C. Beger, P. J. Welch, J. R. Barber, and F. Wong-Staal C-SPACE (cleavage-specific amplification of cDNA ends): a novel method of ribozyme-mediated gene identification Nucleic Acids Res., October 1, 2001; 29(19): e94 - e94. [Abstract] [Full Text] [PDF]
|
|