The kinesin-5 tail domain directly modulates the mechanochemical cycle of the motor domain for anti-parallel microtubule sliding
Abstract
Kinesin-5 motors organize mitotic spindles by sliding apart microtubules. They are homotetramers with dimeric motor and tail domains at both ends of a bipolar minifilament. Here, we describe a regulatory mechanism involving direct binding between tail and motor domains and its fundamental role in microtubule sliding. Kinesin-5 tails decrease microtubule-stimulated ATP-hydrolysis by specifically engaging motor domains in the nucleotide-free or ADP states. Cryo-EM reveals that tail binding stabilizes an open motor domain ATP-active site. Full-length motors undergo slow motility and cluster together along microtubules, while tail-deleted motors exhibit rapid motility without clustering. The tail is critical for motors to zipper together two microtubules by generating substantial sliding forces. The tail is essential for mitotic spindle localization, which becomes severely reduced in tail-deleted motors. Our studies suggest a revised microtubule-sliding model, in which kinesin-5 tails stabilize motor domains microtubule-bound states by slowing ATP-binding resulting in high-force production at both homotetramer ends.
Data availability
Two atomic coordinate files for Dm-KLP61F motor ATP-like MT(alpha-beta-tubulin) model is available at Protein Data Bank (PDB-ID: #XXXX. The Dm-KLP61F motor nucleotide-free MT(alpha-beta-tubulin) asymmetric unit Protein Data BankPDB-ID: #XXXXThe refined Dm-KLP61F motor AMPPNP MT cryo-EM map is available at the Electron microscopy Data bank (EMBD) EMDB ID:#XXXXand the Dm-KLP61F motor-tail nucleotide free MT cryo-EM map is available at Electron microscopy Data bank (EMBD) EMDB-iD:#XXXXDm-KLP61F motor-tail nucleotide free MT cryo-EM map (focused 3D-classification map) is available at the Electron microscopy Data bank (EMBD)EMDB-ID:#XXXX
Article and author information
Author details
Funding
National Science Foundation (1615991)
- Jawdat Al-Bassam
National Institutes of Health (GM110283)
- Jawdat Al-Bassam
National Institutes of Health (GM121491)
- Jason Stumpff
National Institutes of Health (GM130556)
- Jason Stumpff
Israel Science Foundation (ISF 386/18)
- Larisa Gheber
United States-Israel Binational Science Foundation (BSF-2015851)
- Larisa Gheber
National Institutes of Health (GM130556)
- Richard J McKenney
National Institutes of Health (GM052468)
- Ron Milligan
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Andrew P Carter, MRC Laboratory of Molecular Biology, United Kingdom
Publication history
- Received: August 16, 2019
- Accepted: January 16, 2020
- Accepted Manuscript published: January 20, 2020 (version 1)
- Version of Record published: February 12, 2020 (version 2)
Copyright
© 2020, Bodrug et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
Metrics
-
- 3,129
- Page views
-
- 440
- Downloads
-
- 14
- Citations
Article citation count generated by polling the highest count across the following sources: Crossref, PubMed Central, Scopus.
Download links
Downloads (link to download the article as PDF)
Open citations (links to open the citations from this article in various online reference manager services)
Cite this article (links to download the citations from this article in formats compatible with various reference manager tools)
Further reading
-
- Cell Biology
- Neuroscience
Neurons form dense neural circuits by connecting to each other via synapses and exchange information through synaptic receptors to sustain brain activities. Excitatory postsynapses form and mature on spines composed predominantly of actin, while inhibitory synapses are formed directly on the shafts of dendrites where both actin and microtubules (MTs) are present. Thus, it is the accumulation of specific proteins that characterizes inhibitory synapses. In this study, we explored the mechanisms that enable efficient protein accumulation at inhibitory postsynapse. We found that some inhibitory synapses function to recruit the plus end of MTs. One of the synaptic organizers, Teneurin-2 (TEN2), tends to localize to such MT-rich synapses and recruits MTs to inhibitory postsynapses via interaction with MT plus-end tracking proteins EBs. This recruitment mechanism provides a platform for the exocytosis of GABAA receptors. These regulatory mechanisms could lead to a better understanding of the pathogenesis of disorders such as schizophrenia and autism, which are caused by excitatory/inhibitory (E/I) imbalances during synaptogenesis.
-
- Cell Biology
Different anatomical locations of the body skin show differences in their gene expression patterns depending on different origins, and the inherent heterogeneous information can be maintained in adults. However, highly resolvable cellular specialization is less well characterized in different anatomical regions of the skin. Pig is regarded as an excellent model animal for human skin research in view of its similar physiology to human. In this study, single-cell RNA sequencing was performed on pig skin tissues from six different anatomical regions of Chenghua (CH) pigs, with a superior skin thickness trait, and the back site of large white (LW) pigs. We obtained 233,715 cells, representing seven cell types, among which we primarily characterized the heterogeneity of the top three cell types, including smooth muscle cells (SMCs), endothelial cells (ECs), and fibroblasts (FBs). Then, we further identified several subtypes of SMCs, ECs, and FBs, and discovered the expression patterns of site-specific genes involved in some important pathways such as the immune response and extracellular matrix (ECM) synthesis in different anatomical regions. By comparing differentially expressed genes of skin FBs among different anatomical regions, we considered TNN, COL11A1, and INHBA as candidate genes for facilitating ECM accumulation. These findings of heterogeneity in the main skin cell types from different anatomical sites will contribute to a better understanding of inherent skin information and place the potential focus on skin generation, transmission, and transplantation, paving the foundation for human skin priming.