Document Detail

On the rigidity of the cytoskeleton: are MAPs crosslinkers or spacers of microtubules?
MedLine Citation:
PMID:  10976876     Owner:  NLM     Status:  MEDLINE    
Microtubules are fibers of the cytoskeleton involved in mitosis, intracellular transport, motility and other functions. They contain microtubule-associated proteins (MAPs) bound to their surface which stabilize microtubules and promote their assembly. There has been a debate on additional functions of MAPs, e.g. whether MAPs crosslink microtubules and thus increase their rigidity, or whether they act as spacers between them. We have studied the packing of microtubules in the presence of MAPs by solution X-ray scattering using synchrotron radiation. Microtubules free in solution produce a scattering pattern typical of an isolated hollow cylinder, whereas tightly packed microtubules generate a pattern dominated by interparticle interference. The interference patterns are interpreted in terms of the Hosemann paracrystal concept, adapted for arrays of parallel fibers with hexagonal arrangement in the plane perpendicular to the fiber axes (Briki et al., 1998). Microtubules without MAPs can rapidly and efficiently be compressed by centrifugation, as judged by the transition from a "free microtubule" to a "packed microtubule" X-ray scattering pattern. MAPs make the microtubule array highly resistant to packing, even at high centrifugal forces. This emphasizes the role of MAPs as spacers of microtubules rather than crosslinkers. A possible function is to keep the microtubule tracks free for the approach of motor proteins carrying vesicle or organelle cargoes along microtubules.
A Marx; J Pless; E M Mandelkow; E Mandelkow
Related Documents :
20498706 - Tip1/clip-170 protein is required for correct chromosome poleward movement in fission y...
1036286 - Mitosis and cytokinesis in the dinoflagellate amphidinium carterae.
8013256 - A stable dicentric chromosome: both centromeres develop kinetochores and attach to the ...
21738686 - X chromosome inactivation and differentiation occur readily in es cells doubly-deficien...
18364116 - A novel candidate locus on chromosome 11p14.1-p11.2 for autosomal dominant hereditary s...
9783846 - Scoring criteria for preimplantation genetic diagnosis of numerical abnormalities for c...
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  Cellular and molecular biology (Noisy-le-Grand, France)     Volume:  46     ISSN:  0145-5680     ISO Abbreviation:  Cell. Mol. Biol. (Noisy-le-grand)     Publication Date:  2000 Jul 
Date Detail:
Created Date:  2000-10-12     Completed Date:  2000-10-12     Revised Date:  2003-11-14    
Medline Journal Info:
Nlm Unique ID:  9216789     Medline TA:  Cell Mol Biol (Noisy-le-grand)     Country:  FRANCE    
Other Details:
Languages:  eng     Pagination:  949-65     Citation Subset:  IM    
Max-Planck-Unit for Structural Molecular Biology, Hamburg, Germany.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Brain Chemistry
Cross-Linking Reagents
Cytoskeleton / chemistry*
Microtubule-Associated Proteins / chemistry*
Microtubules / chemistry*
Models, Chemical
Scattering, Radiation
Tubulin / chemistry
Reg. No./Substance:
0/Cross-Linking Reagents; 0/Microtubule-Associated Proteins; 0/Tubulin

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Detection and characterization of an intermediate conformation during the divalent ion-dependent swe...
Next Document:  Lipid-DNA and lipid-polyelectrolyte mesophases: structure and exchange kinetics.