Insights into EB1 structure and the role of its C-terminal domain for discriminating microtubule tips from the lattice

RM Buey, R Mohan, Kris Leslie, T Walzthoeni, JH Missimer, A Menzel, S Bjelic, K Bargsten, I Grigoriev, Ihor Smal, Erik Meijering, R Aebersold, Anna Akhmanova, MO Steinmetz

Research output: Contribution to journalArticleAcademicpeer-review

54 Citations (Scopus)


End-binding proteins (EBs) comprise a conserved family of microtubule plus end-tracking proteins. The concerted action of calponin homology (CH), linker, and C-terminal domains of EBs is important for their autonomous microtubule tip tracking, regulation of microtubule dynamics, and recruitment of numerous partners to microtubule ends. Here we report the detailed structural and biochemical analysis of mammalian EBs. Small-angle X-ray scattering, electron microscopy, and chemical cross-linking in combination with mass spectrometry indicate that EBs are elongated molecules with two interacting CH domains, an arrangement reminiscent of that seen in other microtubule-and actin-binding proteins. Removal of the negatively charged C-terminal tail did not affect the overall conformation of EBs; however, it increased the dwell times of EBs on the microtubule lattice in microtubule tip-tracking reconstitution experiments. An even more stable association with the microtubule lattice was observed when the entire negatively charged C-terminal domain of EBs was replaced by a neutral coiled-coil motif. In contrast, the interaction of EBs with growing microtubule tips was not significantly affected by these C-terminal domain mutations. Our data indicate that long-range electrostatic repulsive interactions between the C-terminus and the microtubule lattice drive the specificity of EBs for growing microtubule ends.
Original languageUndefined/Unknown
Pages (from-to)2912-2923
Number of pages12
JournalMolecular Biology of the Cell
Issue number16
Publication statusPublished - 2011

Research programs

  • EMC NIHES-03-30-03

Cite this