2. Academic Validation
  3. MK-STYX Alters the Morphology of Primary Neurons, and Outgrowths in MK-STYX Overexpressing PC-12 Cells Develop a Neuronal Phenotype

MK-STYX Alters the Morphology of Primary Neurons, and Outgrowths in MK-STYX Overexpressing PC-12 Cells Develop a Neuronal Phenotype

  • Front Mol Biosci. 2017 Nov 16;4:76. doi: 10.3389/fmolb.2017.00076.
Dallas A Banks 1,  Arya Dahal 1,  Alexander G McFarland 1,  Brittany M Flowers 1 2,  Christina A Stephens 3,  Benjamin Swack 1,  Ayele Gugssa 4,  Winston A Anderson 4,  Shantá D Hinton 1
Affiliations

Affiliations

  • 1 Department of Biology, Integrated Science Center, College of William and Mary, Williamsburg, VA, United States.
  • 2 National Cancer Institute, National Institutes of Health, Bethesda, MD, United States.
  • 3 Department of Chemistry, Integrated Science Center, College of William and Mary, Williamsburg, VA, United States.
  • 4 Department of Biology, Howard University, Washington, DC, United States.
PMID: 29250526 DOI: 10.3389/fmolb.2017.00076
Abstract

We previously reported that the pseudophosphatase MK-STYX (mitogen activated kinase phosphoserine/threonine/tyrosine binding protein) dramatically increases the number of what appeared to be primary neurites in rat pheochromocytoma (PC-12) cells; however, the question remained whether these MK-STYX-induced outgrowths were bona fide neurites, and formed synapses. Here, we report that microtubules and microfilaments, components of the Cytoskeleton that are involved in the formation of neurites, are present in MK-STYX-induced outgrowths. In addition, in response to nerve growth factor (NGF), MK-STYX-expressing cells produced more growth cones than non-MK-STYX-expressing cells, further supporting a model in which MK-STYX has a role in actin signaling. Furthermore, immunoblot analysis demonstrates that MK-STYX modulates actin expression. Transmission electron microscopy confirmed that MK-STYX-induced neurites form synapses. To determine whether these MK-STYX-induced neurites have pre-synaptic or post-synaptic properties, we used classical markers for axons and dendrites, Tau-1 and MAP2 (microtubule associated protein 2), respectively. MK-STYX induced neurites were dopaminergic and expression of both Tau-1 and MAP2 suggests that they have both axonal and dendritic properties. Further studies in rat hippocampal primary neurons demonstrated that MK-STYX altered their morphology. A significant number of primary neurons in the presence of MK-STYX had more than the normal number of primary neurites. Our data illustrate the novel findings that MK-STYX induces outgrowths in PC-12 cells that fit the criteria for neurites, have a greater number of growth cones, form synapses, and have pre-synaptic and post-synaptic properties. It also highlights that the pseudophosphatase MK-STYX significantly alters the morphology of primary neurons.

Keywords

MAP-2; Tau-1; neurite; neuronal differentiation; pseudophosphatase; synapses.

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