Partial abstract: “[W]e have used [C. elegans] to interrogate PBO-1's mechanism of action. Using fluorescent tags to monitor Na+/H+ exchanger trafficking and localization, we found that loss of either PBO-1 binding or activity caused NHX-7 to accumulate in late endosomes/lysosomes. [These and other results lead us to] conclude that the role of CHP in Na+/H+ exchanger regulation differs between apical and basolateral transporters. This further emphasizes the importance of proper targeting of Na+/H+ exchangers and the critical role of CHP family proteins in this process.”
Goldman, Aaron David, Assistant Professor of Biology, Joshua T. Beatty '15, and Laura F. Landweber. 2016. The TIM barrel architecture facilitated the early evolution of protein-mediated metabolism. Journal of Molecular Evolution 82 (1) (JAN): 17-26. Access in OhioLINK Electronic Journal Center.
Partial abstract: "We show that [triosephosphate isomerase (TIM) barrel] enzymes corresponding to the most taxonomically broad superfamilies also have the broadest range of functions, often aided by metal and nucleotide-derived cofactors that are thought to reflect an earlier stage of metabolic evolution. By comparison to other putatively ancient protein architectures, we find that the functional diversity of TIM barrel proteins cannot be explained simply by their antiquity. Instead, the breadth of TIM barrel functions can be explained, in part, by the incorporation of a broad range of cofactors, a trend that does not appear to be shared by proteins in general. These results support the hypothesis that the simple and functionally general TIM barrel architecture may have arisen early in the evolution of protein biosynthesis and provided an ideal scaffold to facilitate the metabolic transition from ribozymes, peptides, and geochemical catalysts to modern protein enzymes."