14-3-3σ sequesters cyclin B1-CDC2 complex in cytoplasm, and prevents its entry into nucleus resulting in G2/M cell cycle arrest [ 10, 12].
The results of in vitro experiments demonstrated that JC virus entry into nuclei was observed for 15 different types of cell lines, but among them, virus replication occurred exclusively in human neuroblastoma cells [ 126].
Several viruses target the NPC to gain entry to the nucleus, and dysfunctional transport between the cytoplasm and the nucleus has been implicated in multiple diseases including cancer.
GK interaction with GKRP is needed for entry into the nucleus [ 21] but GKRP is not required for GK to exit the nucleus.
Likewise the decrease in intensity upon entry in the nucleus was unaffected (Fig. 6B and Supplementary Table S8).
Gaining entry into the nucleus of human cells is a technically difficult trick that certain viruses have acquired over the course of evolution.
The metal NPs@PEI-TAT integrate the advantages of metal NPs and peptides: the presence of metal NPs can effectively decrease the cytotoxicity of cationic molecules, making it possible to apply them in biological systems, while the cell penetrating peptides are essential for enhanced cellular and nucleus entry to achieve high transfection efficiency.
For intravascular delivery of NPs, the barrier manifests in the form of: (i) immune clearance in the liver and spleen, (ii) permeation across the endothelium into target tissues, (iii) penetration through the tissue interstitium, (iv) endocytosis in target cells, (v) diffusion through cytoplasm and (vi) eventually entry into the nucleus, if required.
