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bioRxiv · 10.1101/677500

Unique PKD like protein kinase in Entamoeba histolytica regulates vital actin mediated processes

Ghosh, S. K.·Baidya, M.·Nayak, S.·Das, A. K.
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Abstract

Entamoeba histolytica causes widespread amoebiasis in humans. Multiple lines of emerging evidence have identified a repertoire of proteins involved in the process of erythrophagocytosis. However, the early initiation of the erythrophagosome at the site of erythrocytes attachment is not well understood. Here in our study we have identified and characterized a small Protein kinase D like protein (EhPKDL) in Eh, which nucleates actin polymerization and thus mediates many vital processes in Eh including erythrophagocytosis. Following multiple biochemical and biophysical approaches, we have characterized EhPKDL and have shown that EhPKDL can indeed interact and prime the nucleation of monomeric actin for polymerization. Furthermore, we went on to demonstrate the vitality of the EhPKDL in major actin-mediated processes like capping, motility, and erythrophagocytosis following knockdown of EhPKDL in the cellular context. Our study thus provides novel insights into the early actin nucleation in Eh and thus bridges the gap with our previous understanding of the assembly of erythrophagosomes.

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Ghosh, S. K., Baidya, M., Nayak, S., Das, A. K.. 2019-06-20. Unique PKD like protein kinase in Entamoeba histolytica regulates vital actin mediated processes. https://doi.org/10.1101/677500

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