Multivalent electrostatic microtubule interactions of synthetic peptides are sufficient to mimic advanced MAP-like behavior
Research output: Contribution to journal › Research article › Contributed › peer-review
Contributors
Abstract
Microtubule-associated proteins (MAPs) are a functionally highly diverse class of proteins that help to adjust the shape and function of the microtubule cytoskeleton in space and time. For this purpose, MAPs structurally support microtubules, modulate their dynamic instability, or regulate the activity of associated molecular motors. The microtubule-binding domains of MAPs are structurally divergent, but often depend on electrostatic interactions with the negatively charged surface of the microtubule. This suggests that the surface exposure of positive charges rather than a certain structural fold is sufficient for a protein to associate with microtubules. Consistently, positively charged artificial objects have been shown to associate with microtubules and to diffuse along their lattice. Natural MAPs, however, show a more sophisticated functionality beyond lattice-diffusion. Here, we asked whether basic electrostatic interactions are sufficient to also support advanced MAP functionality. To test this hypothesis, we studied simple positively charged peptide sequences for the occurrence of typical MAP-like behavior. We found that a multivalent peptide construct featuring four lysine-alanine heptarepeats (starPEG-(KA7)4)-but not its monovalent KA7-subunits-show advanced, biologically relevant MAP-like behavior: starPEG-(KA7)4 binds microtubules in the low nanomolar range, diffuses along their lattice with the ability to switch between intersecting microtubules, and tracks depolymerizing microtubule ends. Further, starPEG-(KA7)4 promotes microtubule nucleation and growth, mediates depolymerization coupled pulling at plus ends, and bundles microtubules without significantly interfering with other proteins on the microtubule lattice (as exemplified by the motor kinesin-1). Our results show that positive charges and multivalency are sufficient to mimic advanced MAP-like behavior.
Details
Original language | English |
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Pages (from-to) | 2953-2968 |
Number of pages | 16 |
Journal | Molecular Biology of the Cell |
Volume | 30 |
Issue number | 24 |
Publication status | Published - 15 Nov 2019 |
Peer-reviewed | Yes |
External IDs
PubMedCentral | PMC6857568 |
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Scopus | 85075090597 |
ORCID | /0000-0002-0750-8515/work/142235552 |
ORCID | /0000-0003-1884-2284/work/142242162 |
ORCID | /0000-0002-6669-4995/work/142251854 |
Keywords
Research priority areas of TU Dresden
Keywords
- Alanine/metabolism, Animals, Chemistry Techniques, Synthetic/methods, Cytoskeleton/metabolism, Diffusion, Humans, Kinesins/metabolism, Lysine/metabolism, Microtubule-Associated Proteins/metabolism, Microtubules/metabolism, Peptides/chemistry, Polymerization, Protein Binding/physiology, Static Electricity, Tubulin/metabolism