Study of the role of protein eIF5A in specific tranlation using the model Saccharomyces cerevisiae

Abstract

Although the function of eIF5A as translation initiation factor has never been clearly demonstrated, recent results from our laboratory strengthen its involvement with protein synthesis and suggest that its role is more related to the elongation of translation. Others studies also correlated with cell proliferation and transition G1 / S in the cell cycle, suggesting its involvement in translation of specific proteins that act in cell cycle progression. Additionally, it was shown that TIF51A is synthetically lethal YPT1 gene that encodes a protein essential for vesicular transport of proteins from the endoplasmic reticulum (ER) to the Golgi. The discovery of the genetic interaction between and YPT1 TIF51A suggests a connection between translation and the secretory pathway is essential for the process of division and cell cycle progression in S. cerevisiae. Moreover, recent data from our laboratory suggest the involvement of eIF5A in protein translocation into the ER by co-translational pathway. To confirm this hypothesis, and to improve the study eIF5A in translation of a subset of mRNAs, this project intend to evaluate the role of the eIF5A in the co-translationalpathmway of translocation with assays for genetic interaction between mutants of TIF51Aand mutantsof genes that encoding proteins that act in this way, as SRP (Signal Recognition Particle) and the translocon complex. Moreover, studies of differential gene expression by proteomic analysis in mutant eIF5A, previously developed in our laboratory, showed a group of proteins that act in cellular processes in which eIF5A has been involved (translation and cell cycle). To confirm the regulation of translation of this group of proteins by eIF5A, we propose the realization of real-time PCR of mRNAs associated with polysomes to assess their levels of translation comparing wild type and mutants defective in eIF5A. These approaches are important to improve the understanding of the possible role of eIF5A in the specific translation.