ABSTRACT In the present work, computational analyses were applied to study the subcellular localiza-tion and posttranslational modifications of hu-man prion proteins (PrPs). The tentative location of prion protein was determined to be in the nu-cleolus inside the nucleus by the following bio-informatics tools: Hum-PLoc, Euk-PLoc and Nuc-PLoc. Based on our results signal peptides with average of 22 base pairs in N-terminal were identified in human PrPs. This theoretical study demonstrates that PrP is post-translationally modified by: 1) attachment of two N-linked complex carbohydrate moieties (N181 and N197), 2) attachmet of glycosylphosphatidylinositol (GPI) at serine 230 and 3) formation of two di-sulfide bonds between “6–22” and “179–214” cysteines. Furthermore, ten protein kinase phosphorylation sites were predicted in human PrP. The above-noted phosphorylation was car-ried out by PKC and CK2. By using bioinfor-matics tools, we have shown that computation-ally human PrPs locate particularly into the nu-cleolus.
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