Recent studies of translational control suggest that translation termination may not be simply the end of synthesizing a protein but rather be involved in modulating both the translation efficiency and stability of a given transcript. Using recombinant eukaryotic release factor 3 (eRF3) and cellular extracts, we have shown for Saccharomyces cerevisiae that yeast eRF3 and Pab1p can interact. This interaction, mediated by the N+M domain of eRF3 and amino acids 473 to 577 of Pab1p, was demonstrated to be direct by the two-hybrid approach. We confirmed that a genetic interaction exists between eRF3 and Pab1p and showed that Pab1p overexpression enhances the efficiency of termination in SUP35 (eRF3) mutant and [PSI(+)] cells. This effect requires the interaction of Pab1p with eRF3. These data further strengthen the possibility that Pab1p has a role in coupling translation termination events with initiation of translation. Several lines of evidence indicate that Pab1p does not influence [PSI(+)] propagation. First, "[PSI(+)]-no-more" mutations do not affect eRF3-Pab1p two-hybrid interaction. Second, overexpression of PAB1 does not cure the [PSI(+)] phenotype or solubilize detectable amounts of eRF3. Third, prion-curing properties of overexpressed HSP104p, which is required for formation and maintenance of [PSI(+)], were not modified by excess Pab1p.
SciCrunch is a data sharing and display platform. Anyone can create a custom portal where they can select searchable subsets of hundreds of data sources, brand their web pages and create their community. SciCrunch will push data updates automatically to all portals on a weekly basis. User communities can also add their own data to scicrunch, however this is not currently a free service.