Cited by 135Microtubule and mitosis dynamicsCancer Treatment and PharmacologyCellular Mechanics and Interactions

Direct visualization of the microtubule lattice seam both in vitro and in vivo

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Kikkawa, M, Ishikawa, T, Nakata, T, Wakabayashi, T, Hirokawa, N·1994·The Journal of Cell Biology

Abstract

Microtubules are constructed from alpha- and beta-tubulin heterodimers that are arranged into protofilaments. Most commonly there are 13 or 14 protofilaments. A series of structural investigations using both electron microscopy and x-ray diffraction have indicated that there are two potential lattices (A and B) in which the tubulin subunits can be arranged. Electron microscopy has shown that kinesin heads, which bind only to beta-tubulin, follow a helical path with a 12-nm pitch in which subunits repeat every 8-nm axially, implying a primarily B-type lattice. However, these helical symmetry parameters are not consistent with a closed lattice and imply that there must be a discontinuity or "seam" along the microtubule. We have used quick-freeze deep-etch electron microscopy to obtain the first direct evidence for the presence of this seam in microtubules formed either in vivo or in vitro. In addition to a conventional single seam, we have also rarely found microtubules in which there is more than one seam. Overall our data indicates that microtubules have a predominantly B lattice, but that A lattice bonds between tubulin subunits are found at the seam. The cytoplasmic microtubules in mouse nerve cells also have predominantly B lattice structure and A lattice bonds at the seam. These observations have important implications for the interaction of microtubules with MAPs and with motor proteins, and for example, suggest that kinesin motors may follow a single protofilament track.

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Crossref · 10.1083/jcb.127.6.1965

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  • So-called B-lattice brain microtubules have multiple seams involving four or more protofilaments, so A-lattice configuration occurs in a third of them, and other work shows mixed A and B lattice microtubules.

    “However these 'B-lattice' [156,157] brain MTs have multiple seams involving 4 or more or protofilaments, so A-lattice configuration occurs in a third of so-called B-lattice MTs.Other work shows mixed A and B lattice microtubules [158].”

    From Consciousness in the universe (2014) · cites this paper as [157]

    The Occurrence of Seam Lines section reports multiple seams, but only 3 of 235 microtubules examined in vitro (1.3%) had a double seam line. The Double Seam Lines section (pp. 1969–1970) describes a model involving three protofilaments and says no double seam line was observed in vivo. The paper therefore does not support the claims that brain microtubules have seams involving four or more protofilaments or that a third of B-lattice microtubules have the proposed A-lattice configuration; the separately cited ‘other work’ is not attributed to this source. (LLM, conf=0.90)

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Authors
Kikkawa, M., Ishikawa, T., Nakata, T., Wakabayashi, T., & Hirokawa, N.
Affiliations
The University of Tokyo (JP)
Venue
The Journal of Cell Biology
Published
1994-12-15
Volume
127
Issue
6
Pages
1965-1971
ISSN
  • 0021-9525 (ISSN-L)
  • 1540-8140
OpenAlex
W2045594387
Cited by
135
References
25
Citations by year
2026: 5 · 2025: 1 · 2024: 4 · 2023: 4 · 2022: 2 · 2021: 6 · 2020: 4 · 2019: 3 · 2018: 4 · 2017: 5 · 2016: 2 · 2015: 3 · 2014: 4 · 2013: 8 · 2012: 2
FWCI
3.60
Type
journal article
Language
en
Open access
Licence
cc-by-nc-sa
Locations
  • The Journal of Cell Biology (publishedVersion)
  • PubMed Central (publishedVersion, cc-by-nc-sa)
  • PubMed (publishedVersion)
Topics
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Cell Biology › Microtubule and mitosis dynamics
  • Health Sciences › Medicine › Oncology › Cancer Treatment and Pharmacology
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Cell Biology › Cellular Mechanics and Interactions
Keywords
microtubule lattice, protofilaments, tubulin heterodimers, kinesin, helical symmetry, microtubule structure, microtubule-associated proteins, motor proteins
MeSH terms
Animals, Cerebellum, Freeze Etching, Image Processing, Computer-Assisted, Microscopy, Electron, Microtubules, Models, Molecular, Models, Structural, Protein Binding, Recombinant Proteins, Swine, Tubulin, Kinesins, Mice

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