Microtubule and MAPs

Abstract

Microtubules are implicated in many essential cellular processes such as architecture, cell division, and intracellular traffic, due to their dynamic instability. This dynamicity is tightly regulated by microtubule-associated proteins (MAPs), such as tau and stathmin. Despite extensive studies motivated by their central role in physiological functions and pathological role in neurodegenerative diseases and cancer, the precise mechanisms of tau and stathmin binding to tubulin and their consequences on microtubule stability are still not fully understood. One of the most crucial points missing is a quantitative thermodynamic description of their interaction with tubulin/microtubules and of the tubulin complexes formed upon these interactions. In this chapter, we will focus on the use of analytical ultracentrifugation, isothermal titration calorimetry, and nuclear magnetic resonance-three powerful and complementary techniques in the field of MAP-tubulin/microtubule interactions, in addition to the spectrometric techniques and co-sedimentation approach. We will present the limits of these techniques to study this particular interaction and precautions that need to be taken during MAPs preparation. Understanding the molecular mechanisms that govern MAPs action on microtubular network will not only shed new light on the role of this crucial family of protein in the biology of the cell, but also hopefully open new paths to increase the therapeutic efficiency of microtubule-targeting drugs in cancers therapies and neurodegeneratives diseases prevention.

Identification, design and synthesis of tubulin-derived peptides as novel hyaluronan mimetic ligands for the receptor for hyaluronan-mediated motility (RHAMM/HMMR)

“…The motif, EEXEE (X = G or A) is present in the peptides with the highest affinity for RHAMM. Our present results are in agreement with previous reports that the short sequence EEGEE [58][59][60] could be involved in tubulin and MAP binding, a family of proteins that shares sequence homology to RHAMM. Despite this role of acidic functional groups in HA:RHAMM interactions, our results also indicate additional, possibly conformational influences.…”

GEF-H1 Signaling upon Microtubule Destabilization Is Required for Dendritic Cell Activation and Specific Anti-tumor Responses

“…Microtubule binding of GEFH1 variants was performed by a standard microtubule co-sedimentation assay (Devred et al, 2010). Briefly, tubulin at 2 mg/mL in BRB80 buffer (80 mM PIPES-KOH, pH 6.8, 1 mM MgCl 2 , 1 mM EGTA) supplemented with 0.5 mM GTP and 1.25 mM DTT was incubated at 4°C for 5 minutes followed by incubation at 37°C for 10 minutes.…”

Role of Tau as a Microtubule-Associated Protein: Structural and Functional Aspects

“…However, the exact mechanism of assembly and stabilization of MTs by Tau remains challenging to characterize due to the inherent dynamics of the system and the disordered nature of Tau. The number of approaches that have been conducted so far to gain knowledge on this particular interaction is striking (Devred et al, 2010; Nouar et al, 2013; Di Maio et al, 2014; Tsvetkov et al, 2019). Tau is probably the most studied MAP because of its implication in a group of neurodegenerative diseases called tauopathies, associated with Tau aggregation into intraneuronal deposits (Brion et al, 1986), such as frontotemporal dementia (FTD), Alzheimer’s disease (AD) and progressive supranuclear palsy.…”