Amantadine as a regulator of internal ribosome entry site  

作　　者：Ying-ju CHEN Shih-jhan ZENG John TA HSU Jim-tong HORNG Hong-ming YANG Shin-ru SHIH Yu-ting CHU Tzong-yuan WU 

机构地区：[1]Department of Bioscience Technology and Center for Nanotechnology, Chung Yuan Christian University, Chung-Li, Taiwan, China [2]Division of Biotechnology and Pharmaceutical Research, National Health Research Institutes, Taipei, Taiwan, China [3]Department of Chemical Engineering, National Tsing Hua Unversity, Hsinehu, Taiwan, China [4]Department of Biochemistry, Chang Gung University, Kweishan, Taoyuan, Taiwan, China [5]School of Medical Technology, Chang Gung University, Taoyuan, Taiwan & Clinical Virology Laboratory, Department of Clinical Pathology, Chang Gung Memorial Hospital, Taoyuan, Taiwan, China

出　　处：《Acta Pharmacologica Sinica》2008年第11期1327-1333,共7页中国药理学报（英文版）

摘　　要：Aim： Studies of eukaryotes have yielded 2 translation initiation mechanisms： a classical cap-dependent mechanism and a cap-independent mechanism proceeding through the internal ribosomal entry site （IRES）. We hypothesized that it might be possible to identify compounds that may distinguish between cap-dependent translation and cap-independent IRES-mediated translation. Methods： To facilitate compound screening, we developed bicistronic reporter constructs containing a β-galactosidase gene （β-gal） and a secreted human placental alkaline phosphatase （SEAP） reporter gene. Following transcription, the β-gal gene is translated by a cap-dependent mechanism, while SEAP expression is controlled by the IRES derived from either enterovirus 71 （EV-71） or encephalomyocarditis virus （EMCV）. This assay could potentially identify compounds that inhibit SEAP expression （cap-independent） without affecting β-gal activity （cap-dependent）. Results： Using a bicistronic plasmid-based transient transfection assay in the COS-1 cells, we identified amantadine, a compound that inhibited the IRES of EV71- and EMCV-mediated cap-independent translation but did not interfere with cap-dependent translation when the dose of amantadine was lower than 0.25 mg/mL. Conclusion： These results imply that amantadine may distinguish between cap-dependent translation and cap-independent IRES-mediated translation and can be used to regulate gene expression at a translational level.Aim： Studies of eukaryotes have yielded 2 translation initiation mechanisms： a classical cap-dependent mechanism and a cap-independent mechanism proceeding through the internal ribosomal entry site （IRES）. We hypothesized that it might be possible to identify compounds that may distinguish between cap-dependent translation and cap-independent IRES-mediated translation. Methods： To facilitate compound screening, we developed bicistronic reporter constructs containing a β-galactosidase gene （β-gal） and a secreted human placental alkaline phosphatase （SEAP） reporter gene. Following transcription, the β-gal gene is translated by a cap-dependent mechanism, while SEAP expression is controlled by the IRES derived from either enterovirus 71 （EV-71） or encephalomyocarditis virus （EMCV）. This assay could potentially identify compounds that inhibit SEAP expression （cap-independent） without affecting β-gal activity （cap-dependent）. Results： Using a bicistronic plasmid-based transient transfection assay in the COS-1 cells, we identified amantadine, a compound that inhibited the IRES of EV71- and EMCV-mediated cap-independent translation but did not interfere with cap-dependent translation when the dose of amantadine was lower than 0.25 mg/mL. Conclusion： These results imply that amantadine may distinguish between cap-dependent translation and cap-independent IRES-mediated translation and can be used to regulate gene expression at a translational level.

关 键 词：AMANTADINE Enterovirus 71 internal ribosomeentry site riboswich 

分 类 号：R574[医药卫生—消化系统]