An N-terminal motif unique to primate tau enables differential protein-protein interactions

作者:Stefanoska Kristie; Volkerling Alexander; Bertz Josefine; Poljak Anne; Ke Yazi D; Ittner Lars M*; Ittner Arne
来源:JOURNAL OF BIOLOGICAL CHEMISTRY, 2018, 293(10): 3710-3719.
DOI:10.1074/jbc.RA118.001784

摘要

Compared with other mammalian species, humans are particularly susceptible to tau-mediated neurodegenerative disorders. Differential interactions of the tau protein with other proteins are critical for mediating tau's physiological functions as well as tau-associated pathological processes. Primate tau harbors an 11-amino acid-long motif in its N- terminal region (residues 18-28), which is not present in non-primate species and whose function is unknown. Here, we used deletion mutagenesis to remove this sequence region from the longest human tau isoform, followed by glutathione S-transferase (GST) pulldown assays paired with isobaric tags for relative and absolute quantitation (iTRAQ) multiplex labeling, a quantitative method to measure protein abundance by mass spectrometry. Using this method, we found that the primate-specific N- terminal tau motif differentially mediates interactions with neuronal proteins. Among these binding partners are proteins involved in synaptic transmission (synapsin-1 and synaptotagmin-1) and signaling proteins of the 14-3-3 family. Furthermore, we identified an interaction of tau with a member of the annexin family (annexin A5) that was linked to the 11-residue motif. These results suggest that primate Tau has evolved specific residues that differentially regulate protein-protein interactions compared with tau proteins from other non-primate mammalian species. Our findings provide in vitro insights into tau's interactions with other proteins that may be relevant to human disease.

  • 出版日期2018-3-9