Changes of the transient secondary structure motifs within Tau protein induced by its phosphorylation

Radek CRHA, Alena HOFROVÁ, Norbert GAŠPARIK, Jozef HRITZ*

 CEITEC-MU, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic

jozef.hritz@ceitec.muni.cz, radek.crha@ceitec.muni.cz

 

Pathological conformational changes as well as hyperphosphorylation of microtubule-associated protein Tau are often connected with many neurodegenerative diseases (e.g., Alzheimer's disease).[1] Due to the lack of tertiary structure Tau belongs to the group of intrinsically disordered proteins (IDPs). The widely used techniques Cryo-EM and X-ray crystallography are not sufficient for structural characterization of IDPs. On the other hand, nuclear magnetic resonance (NMR) can provide structural information at single residue resolution.

Due to Tau’s intrinsically disordered character as well as the high content of prolines in its primary structure we employed 5D 13C-directly detected multidimensional NMR experiments to assign the backbone and obtain structural characterization of Tau.[2] With this approach, we have successfully assigned backbone and aliphatic side-chain chemical shifts (CS) of Tau protein in the native as well as phosphorylated (by PKA) form. Based on the CS we performed secondary structure propensity analysis  X-Pro peptide bonds conformation prediction. Moreover, we monitored kinetics of PKA phosphorylation of Tau using time-resolved NMR experiment.

[1]        K. Kitoka, R. Skrabana, N. Gasparik, J. Hritz, and K. Jaudzems, “NMR Studies of Tau Protein in Tauopathies,” Front. Mol. Biosci., vol. 8, no. November, pp. 1–16, 2021, doi: 10.3389/fmolb.2021.761227.

[2]        J. Nováèek, L. Janda, R. Dopitová, L. Žídek, and V. Sklenáø, “Efficient protocol for backbone and side-chain assignments of large, intrinsically disordered proteins: Transient secondary structure analysis of 49.2 kDa microtubule associated protein 2c,” J. Biomol. NMR, vol. 56, no. 4, pp. 291–301, 2013, doi: 10.1007/s10858-013-9761-7.

This research was funded by Czech Science Foundation (GF20-05789L). Project was also supported by Grant agency of Masaryk university Excellent diploma thesis programme (project: MUNI/C/0040/2021). NMR measurements was supported from CIISB research infrastructure project LM2018127 funded by MEYS CR.