Characterization of MAP1B heavy chain interaction with actin.

Details

Serval ID
serval:BIB_CAC1FB83C41E
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
Characterization of MAP1B heavy chain interaction with actin.
Journal
Brain Research Bulletin
Author(s)
Cueille N., Blanc C.T., Popa-Nita S., Kasas S., Catsicas S., Dietler G., Riederer B.M.
ISSN
0361-9230 (Print)
ISSN-L
0361-9230
Publication state
Published
Issued date
2007
Volume
71
Number
6
Pages
610-618
Language
english
Abstract
Microtubule-associated protein 1B is an essential protein during brain development and neurite outgrowth and was studied by several assays to further characterize actin as a major interacting partner. Tubulin and actin co-immunoprecipitated with MAP1B at similar ratios throughout development. Their identity was identified by mass spectrometry and was confirmed by Western blots. In contrast to previous reports, the MAP1B-actin interaction was not dependent on the MAP1B phosphorylation state, since actin was precipitated from brain tissue throughout development at similar ratios and equal amounts were precipitated before and after dephosphorylation with alkaline phosphatase. MAP1B heavy chain was able to bind actin directly and therefore the N-terminal part of MAP1B heavy chain must also contain an actin-binding site. The binding force of this interaction was measured by atomic force microscopy and values were in the same range as those of MAP1B binding to tubulin or that measured in MAP1B self-aggregation. Aggregation was confirmed by negative staining and electron microscopy. Experiments including COS-7 cells, PC12 cells, cytochalasin D and immunocytochemistry with subsequent confocal laser microscopy, suggested that MAP1B may bind to actin but has no obvious microfilament stabilizing effect. We conclude, that the MAP1B heavy chain has a microtubule-stabilization effect, and contains an actin-binding site that may play a role in the crosslinking of actin and microtubules, a function that may be important in neurite elongation.
Keywords
Actin Cytoskeleton/metabolism, Actins/metabolism, Animals, Animals, Newborn, Binding Sites/physiology, Brain/growth & development, Brain/metabolism, COS Cells, Cercopithecus aethiops, Macromolecular Substances/chemistry, Macromolecular Substances/metabolism, Mass Spectrometry, Mice, Microscopy, Atomic Force, Microscopy, Electron, Microtubule-Associated Proteins/chemistry, Microtubule-Associated Proteins/metabolism, Microtubules/metabolism, Microtubules/ultrastructure, Neurites/metabolism, Neurites/ultrastructure, PC12 Cells, Phosphorylation, Protein Binding/physiology, Protein Subunits/chemistry, Protein Subunits/metabolism, Rats, Subcellular Fractions
Pubmed
Web of science
Create date
24/01/2008 15:34
Last modification date
20/08/2019 16:45
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