Unknown

Dataset Information

0

Novel MicroRNA Reporter Uncovers Repression of Let-7 by GSK-3?.


ABSTRACT: Several members of the let-7 microRNA family are downregulated in ovarian and other cancers. They are thought to act as tumor suppressors by lowering growth-promoting and anti-apoptotic proteins. In order to measure cellular let-7 levels systematically, we have developed a highly sensitive let-7 reporter assay system based on the expression of a chimeric mRNA that contains the luciferase coding region and a 3'-untranslated region (UTR) bearing two let-7-binding sites. In cells expressing the reporter construct, termed pmirGLO-let7, luciferase activity was high when let-7 was absent, while luciferase activity was low when let-7 levels were elevated. The ovarian cancer cell lines BG-1 and UCI-101 were transfected with the let-7 reporter and surveyed with a library of kinase inhibitors in order to identify pathways affecting let-7 activity. Among the inhibitors causing changes in endogenous let-7 abundance, the lowering of glycogen synthase kinase 3 (GSK-3)? function specifically increased let-7 levels and lowered luciferase activity. Similarly, silencing GSK-3? increased both mature and primary-let-7 levels in BG-1 cells, and decreased BG-1 cell survival. Further studies identified p53 as a downstream effector of the GSK-3?-mediated repression of let-7 biosynthesis. Our studies highlight GSK-3? as a novel therapeutic target in ovarian tumorigenesis.

SUBMITTER: Guo R 

PROVIDER: S-EPMC3694080 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

altmetric image

Publications

Novel MicroRNA Reporter Uncovers Repression of Let-7 by GSK-3β.

Guo Rong R   Abdelmohsen Kotb K   Morin Patrice J PJ   Gorospe Myriam M  

PloS one 20130626 6


Several members of the let-7 microRNA family are downregulated in ovarian and other cancers. They are thought to act as tumor suppressors by lowering growth-promoting and anti-apoptotic proteins. In order to measure cellular let-7 levels systematically, we have developed a highly sensitive let-7 reporter assay system based on the expression of a chimeric mRNA that contains the luciferase coding region and a 3'-untranslated region (UTR) bearing two let-7-binding sites. In cells expressing the rep  ...[more]

Similar Datasets

| S-EPMC6627301 | biostudies-literature
| S-EPMC4465779 | biostudies-literature
| S-EPMC4359369 | biostudies-literature
| S-EPMC2906317 | biostudies-literature
| S-EPMC4940420 | biostudies-literature
| S-EPMC10027610 | biostudies-literature
| S-EPMC2628762 | biostudies-literature
| S-EPMC3049892 | biostudies-literature
| S-EPMC3526310 | biostudies-literature
| S-EPMC6765313 | biostudies-literature