van Riel WE Rai A Bianchi S Katrukha EA Liu Q Heck AJ Hoogenraad CC Steinmetz MO Kapitein LC Akhmanova A 2017 Microtubules are dynamic polymers that in cells can grow, shrink or pause, but the factors that promote pausing are poorly understood. Here, we show that the mammalian kinesin-4 KIF21B is a processive motor that can accumulate at microtubule plus ends and induce pausing. A few KIF21B molecules are sufficient to induce strong growth inhibition of a microtubule plus end in vitro. This property depends on non-motor microtubule-binding domains located in the stalk region and the C-terminal WD40 domain. The WD40-containing KIF21B tail displays preference for a GTP-type over a GDP-type microtubule lattice and contributes to the interaction of KIF21B with microtubule plus ends. KIF21B also contains a motor-inhibiting domain that does not fully block the interaction of the protein with microtubules, but rather enhances its pause-inducing activity by preventing KIF21B detachment from microtubule tips. Thus, KIF21B combines microtubule-binding and regulatory activities that together constitute an autonomous microtubule pausing factor. https://sonar.ch/global/documents/886 eng info:eu-repo/semantics/altIdentifier/doi/10.7554/eLife.24746 info:eu-repo/semantics/altIdentifier/pmid/28290984 eLife. - 2017 EB1 KIF21B Kinesin Kinesin-4 biophysics cell biology human microtubule dynamics pausing structural biology Animals COS Cells Chlorocebus aethiops HEK293 Cells Humans Kinesin Microtubules Protein Binding Protein Domains Protein Interaction Mapping Protein Multimerization Kinesin-4 KIF21B is a potent microtubule pausing factor. http://purl.org/coar/resource_type/c_6501