engleski

The analysis of cell-adhesion glycoprotein neuroplastin expression during cellular differentiation in SH-SY5Y neuroblastoma cells

Neuroplastin (Np), a transmembrane cell-adhesion glycoprotein, has been implicated in several key neuronal functions including promoting neurite outgrowth and synaptic plasticity. Np exists in two isoforms, neuron-specific Np65 and Np55 which is detected in wide range of tissues and has been additionally found in several types of malignancies in humans. However, an adhesive function and a potential role of Np55 in altered cellular proliferation has not been clarified. We investigated whether cellular differentiation affects changes of expression of two neuroplastin isoforms in vitro. For that purpose, we used neuroblastoma cell line SH-SY5Y and analyzed the expression of Np65 and Np55 by immunocytochemistry and Western blot in non- differentiated cells compared to differentiated cells. To achieve differentiation, cells were treated with 1 μM and 10 μM retinoic acid for 3 and 5 days. The differentiation was confirmed by staining for neuronal marker synaptophysin. Additionally, GM1 ganglioside expression was also analyzed since our research showed that Np expression and localization depends on ganglioside composition in murine brain tissue and that Np co-localizes with specific ganglioside species in primary neuronal cultures. Preliminary results show changes of neuroplastin expression related to cell- differentiation stage, i.e. higher abundance of neuronal-specific isoform Np65 in differentiated vs. non- differentiated cells in which Np55 isoform predominates. Since it is well established that membrane organization and protein-lipid interactions underlie crucial (patho)physiological cellular events, further study is needed to clarify functional consequences of observed Np55 to Np65 shift occurring with cellular differentiation, and especially in association to ganglioside composition.

neuroplastin ; GM1 ; differentiation ; neuroblastoma

nije evidentirano