Tropomyosins induce neuritogenesis and determine neurite branching patterns in B35 neuroblastoma cells

Nikki Margarita Curthoys; Hannah Freittag; Andrea Connor; Melissa Desouza; Merryn Brettle; Anne Poljak; Amelia Hall; Edna Hardeman; Galina Schevzov; Peter William Gunning; Thomas Fath

doi:10.1016/j.mcn.2013.10.011

Tropomyosins induce neuritogenesis and determine neurite branching patterns in B35 neuroblastoma cells

Mol Cell Neurosci. 2014 Jan:58:11-21. doi: 10.1016/j.mcn.2013.10.011. Epub 2013 Nov 6.

Authors

Affiliations

¹ Neurodegeneration and Repair Unit, School of Medical Sciences, The University of New South Wales, Sydney NSW 2052, Australia; Oncology Research Unit, School of Medical Sciences, The University of New South Wales, Sydney NSW 2052, Australia.
² Neurodegeneration and Repair Unit, School of Medical Sciences, The University of New South Wales, Sydney NSW 2052, Australia; Neuromuscular and Regenerative Medicine Unit, School of Medical Sciences, The University of New South Wales, Sydney NSW 2052, Australia.
³ Neurodegeneration and Repair Unit, School of Medical Sciences, The University of New South Wales, Sydney NSW 2052, Australia.
⁴ Bioanalytical Mass Spectrometry Facility, Bioanalytical Centre, The University of New South Wales, Sydney, NSW 2052, Australia.
⁵ Neuromuscular and Regenerative Medicine Unit, School of Medical Sciences, The University of New South Wales, Sydney NSW 2052, Australia.
⁶ Oncology Research Unit, School of Medical Sciences, The University of New South Wales, Sydney NSW 2052, Australia.
⁷ Neurodegeneration and Repair Unit, School of Medical Sciences, The University of New South Wales, Sydney NSW 2052, Australia. Electronic address: t.fath@unsw.edu.au.

PMID: 24211701
DOI: 10.1016/j.mcn.2013.10.011

Abstract

Background: The actin cytoskeleton is critically involved in the regulation of neurite outgrowth.

Results: The actin cytoskeleton-associated protein tropomyosin induces neurite outgrowth in B35 neuroblastoma cells and regulates neurite branching in an isoform-dependent manner.

Conclusions: Our data indicate that tropomyosins are key regulators of the actin cytoskeleton during neurite outgrowth.

Significance: Revealing the molecular machinery that regulates the actin cytoskeleton during neurite outgrowth may provide new therapeutic strategies to promote neurite regeneration after nerve injury.

Summary: The formation of a branched network of neurites between communicating neurons is required for all higher functions in the nervous system. The dynamics of the actin cytoskeleton is fundamental to morphological changes in cell shape and the establishment of these branched networks. The actin-associated proteins tropomyosins have previously been shown to impact on different aspects of neurite formation. Here we demonstrate that an increased expression of tropomyosins is sufficient to induce the formation of neurites in B35 neuroblastoma cells. Furthermore, our data highlight the functional diversity of different tropomyosin isoforms during neuritogenesis. Tropomyosins differentially impact on the expression levels of the actin filament bundling protein fascin and increase the formation of filopodia along the length of neurites. Our data suggest that tropomyosins are central regulators of actin filament populations which drive distinct aspects of neuronal morphogenesis.

Keywords: Actin cytoskeleton; Fascin; Neurite outgrowth; Tropomyosin.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Actin Cytoskeleton / metabolism
Animals
Carrier Proteins / genetics
Carrier Proteins / metabolism
Cell Line, Tumor
Growth Cones / metabolism*
Microfilament Proteins / genetics
Microfilament Proteins / metabolism
Neurites / metabolism*
Neuroblastoma / metabolism
Neurogenesis*
Protein Isoforms / metabolism
Pseudopodia / metabolism
Rats
Tropomyosin / metabolism*

Substances

Carrier Proteins
Microfilament Proteins
Protein Isoforms
Tropomyosin
fascin