Dataset Information

Induction and characterization of taxol-resistance phenotypes with a transiently expressed artificial transcriptional activator library.

ABSTRACT: Phenotype-based functional genomic methods are useful for the identification of genes that are related to a particular biological function or disease. Essential to this approach is the ability to regulate the expression of selected genes. Artificial transcription factors (ATFs) are key molecular tools that selectively regulate gene expression in vivo. Here, we use an ATF library to identify genes that participate in rendering a cell resistant to the drug Taxol, a potent anti-cancer drug that binds to tubulin and inhibits cell division. The library, which encodes ATFs that activate (rather than inhibit) transcription, was introduced into a HeLa cell line, and Taxol-resistant cells were selected. After eight rounds of selection, we identified two ATFs that significantly increased the level of Taxol resistance (TR) in HeLa cells. Gene expression microarray experiments using these ATFs identified 37 co-regulated genes, including genes already known to participate in TR. This study demonstrates that ATF libraries can be used to induce phenotypic alterations in eukaryotic cells and then identify specific genes that are associated with the phenotype of choice.

SUBMITTER: Lee DK

PROVIDER: S-EPMC514398 | biostudies-literature | 2004

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Induction and characterization of taxol-resistance phenotypes with a transiently expressed artificial transcriptional activator library.

Lee Dong-ki DK Kim Yong Ha YH Kim Jin-Soo JS Seol Wongi W

Nucleic acids research 20040810 14

Phenotype-based functional genomic methods are useful for the identification of genes that are related to a particular biological function or disease. Essential to this approach is the ability to regulate the expression of selected genes. Artificial transcription factors (ATFs) are key molecular tools that selectively regulate gene expression in vivo. Here, we use an ATF library to identify genes that participate in rendering a cell resistant to the drug Taxol, a potent anti-cancer drug that bin ...[more]

PMID: 15304545

Similar Datasets

Project description:RationaleEndoplasmic reticulum (ER) stress dysregulates ER proteostasis, which activates the transcription factor, ATF6 (activating transcription factor 6α), an inducer of genes that enhance protein folding and restore ER proteostasis. Because of increased protein synthesis, it is possible that protein folding and ER proteostasis are challenged during cardiac myocyte growth. However, it is not known whether ATF6 is activated, and if so, what its function is during hypertrophic growth of cardiac myocytes.ObjectiveTo examine the activity and function of ATF6 during cardiac hypertrophy.Methods and resultsWe found that ER stress and ATF6 were activated and ATF6 target genes were induced in mice subjected to an acute model of transverse aortic constriction, or to free-wheel exercise, both of which promote adaptive cardiac myocyte hypertrophy with preserved cardiac function. Cardiac myocyte-specific deletion of Atf6 (ATF6 cKO [conditional knockout]) blunted transverse aortic constriction and exercise-induced cardiac myocyte hypertrophy and impaired cardiac function, demonstrating a role for ATF6 in compensatory myocyte growth. Transcript profiling and chromatin immunoprecipitation identified RHEB (Ras homologue enriched in brain) as an ATF6 target gene in the heart. RHEB is an activator of mTORC1 (mammalian/mechanistic target of rapamycin complex 1), a major inducer of protein synthesis and subsequent cell growth. Both transverse aortic constriction and exercise upregulated RHEB, activated mTORC1, and induced cardiac hypertrophy in wild type mouse hearts but not in ATF6 cKO hearts. Mechanistically, knockdown of ATF6 in neonatal rat ventricular myocytes blocked phenylephrine- and IGF1 (insulin-like growth factor 1)-mediated RHEB induction, mTORC1 activation, and myocyte growth, all of which were restored by ectopic RHEB expression. Moreover, adeno-associated virus 9- RHEB restored cardiac growth to ATF6 cKO mice subjected to transverse aortic constriction. Finally, ATF6 induced RHEB in response to growth factors, but not in response to other activators of ATF6 that do not induce growth, indicating that ATF6 target gene induction is stress specific.ConclusionsCompensatory cardiac hypertrophy activates ER stress and ATF6, which induces RHEB and activates mTORC1. Thus, ATF6 is a previously unrecognized link between growth stimuli and mTORC1-mediated cardiac growth.

Dataset Information

Induction and characterization of taxol-resistance phenotypes with a transiently expressed artificial transcriptional activator library.

Publications

Induction and characterization of taxol-resistance phenotypes with a transiently expressed artificial transcriptional activator library.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets