BACKGROUND: The termination of protein synthesis in eukaryotes involves at least two polypeptide release factors (eRFs), eRF1 and eRF3. In mammals two genes encoding eRF3 structural homologues were identified and named GSPT1 and GSPT2. RESULTS: In the present study, we demonstrate that mouse mGSPT2 but not mGSPT1 could functionally substitute the essential yeast gene SUP35. However, we show that the complementation property of mGSPT1 protein is modified when NH2-tagged by GST. Since mGSPT1 and mGSPT2 differ mainly in their N-terminal regions, we developed a series of N-terminal deleted constructs and tested them for complementation in yeast. We found that at least amino acids spanning 84-120 of mGSPT1 prevent the complementation of sup35 mutation. The fact that chimeras between mGSPT1, mGSPT2 and yeast Sup35 complement the disruption of the SUP35 gene indicates that the N-terminal region of mGSPT1 is not sufficient by itself to prevent complementation. Complementation of the mutant with a double disruption of SUP35 and SUP45 genes is obtained when mGSPT2 and human eRF1 are co-expressed but not by co-expression of mGSPT1 and human eRF1. CONCLUSIONS: Our results strongly suggest that the two proteins (mGSPT1 and mGSPT2) are different. We hypothesize that the full length mGSPT1 does not have the properties expected for eRF3.
BACKGROUND: The termination of protein synthesis in eukaryotes involves at least two polypeptide release factors (eRFs), eRF1 and eRF3. In mammals two genes encoding eRF3 structural homologues were identified and named GSPT1 and GSPT2. RESULTS: In the present study, we demonstrate that mousemGSPT2 but not mGSPT1 could functionally substitute the essential yeast gene SUP35. However, we show that the complementation property of mGSPT1 protein is modified when NH2-tagged by GST. Since mGSPT1 and mGSPT2 differ mainly in their N-terminal regions, we developed a series of N-terminal deleted constructs and tested them for complementation in yeast. We found that at least amino acids spanning 84-120 of mGSPT1 prevent the complementation of sup35 mutation. The fact that chimeras between mGSPT1, mGSPT2 and yeastSup35 complement the disruption of the SUP35 gene indicates that the N-terminal region of mGSPT1 is not sufficient by itself to prevent complementation. Complementation of the mutant with a double disruption of SUP35 and SUP45 genes is obtained when mGSPT2 and humaneRF1 are co-expressed but not by co-expression of mGSPT1 and humaneRF1. CONCLUSIONS: Our results strongly suggest that the two proteins (mGSPT1 and mGSPT2) are different. We hypothesize that the full length mGSPT1 does not have the properties expected for eRF3.
Authors: Annabel C Whibley; Vincent Plagnol; Patrick S Tarpey; Fatima Abidi; Tod Fullston; Maja K Choma; Catherine A Boucher; Lorraine Shepherd; Lionel Willatt; Georgina Parkin; Raffaella Smith; P Andrew Futreal; Marie Shaw; Jackie Boyle; Andrea Licata; Cindy Skinner; Roger E Stevenson; Gillian Turner; Michael Field; Anna Hackett; Charles E Schwartz; Jozef Gecz; Michael R Stratton; F Lucy Raymond Journal: Am J Hum Genet Date: 2010-07-22 Impact factor: 11.025
Authors: Chelsea E Powell; Guangyan Du; Jianwei Che; Zhixiang He; Katherine A Donovan; Hong Yue; Eric S Wang; Radosław P Nowak; Tinghu Zhang; Eric S Fischer; Nathanael S Gray Journal: ACS Chem Biol Date: 2020-09-28 Impact factor: 5.100
Authors: He Gong; Nina V Romanova; Kim D Allen; Pavithra Chandramowlishwaran; Kavita Gokhale; Gary P Newnam; Piotr Mieczkowski; Michael Y Sherman; Yury O Chernoff Journal: PLoS Genet Date: 2012-04-19 Impact factor: 5.917
Authors: Svetlana E Moskalenko; Svetlana V Chabelskaya; Sergei G Inge-Vechtomov; Michel Philippe; Galina A Zhouravleva Journal: BMC Mol Biol Date: 2003-02-10 Impact factor: 2.946