The uptake and subcellular localization of the peptide antibiotic edeine a in HeLa cells in suspension culture

1979 ◽  
Vol 124 (2) ◽  
pp. 371-379 ◽  
Author(s):  
Z. Kurylo-Borowska ◽  
J. Heaney-Kieras
Keyword(s):  
Subcellular Localization ◽  
Suspension Culture ◽  
Hela Cells ◽  
Peptide Antibiotic

Long term in vitro suspension culture of Toxoplasma and HeLa cells

1987 ◽  
Vol 264 (3-4) ◽  
pp. 468-477
Author(s):  
Haruhisa Sakurai ◽  
Hiroshi Sakurai ◽  
Tatsuya Tegoshi ◽  
Takao Takagi ◽  
Atsushi Saito ◽  
...  
Keyword(s):  
Suspension Culture ◽  
Hela Cells

scholarly journals Identification of a putative nuclear localization signal in maspin protein shed light into its nuclear import regulation

2018 ◽  
Author(s):  
Jeffrey Reina ◽  
Lixin Zhou ◽  
Marcos R.M. Fontes ◽  
Nelly Panté ◽  
Nathalie Cella
Keyword(s):  
Subcellular Localization ◽  
Nuclear Localization ◽  
Hela Cells ◽  
Nuclear Import ◽  
Nuclear Localization Signal ◽  
Molecular Mechanisms ◽  
Nuclear Translocation ◽  
Biological Activities ◽  
Dependent Manner ◽  
Localization Signal

AbstractMaspin (SERPINB5) is a potential tumor suppressor gene with pleiotropic biological activities, including regulation of cell proliferation, death, adhesion, migration and gene expression. Several studies suggest that subcellular localization plays an essential role on maspin tumor suppression activity. In this study we investigated the molecular mechanisms underlying maspin nucleocytoplasmic shuttling. Anin vitronuclear-import assay using digitonin-permeabilized HeLa cells demonstrated that maspin enters the nucleus by an energy-and carrier-independent mechanism. However, previous studies indicated that maspin subcellular localization is regulated in the cell. Using a nuclear localization signal (NLS) prediction software, we identified a putative NLS in the maspin amino acid sequence. To distinguish between passive and regulated nuclear translocation, maspinNLS or the full-length protein (MaspinFL) were fused to 5GFP, rendering the construct too large to enter the nucleus passively. Unexpectedly, 5GFP-maspinNLS, but not maspinFL-5GFP, entered the nucleus of HeLa cells. Dominant-negative Ran-GTPase mutants RanQ69L or RanT24N, suppressed 5GFP-maspinNLS nuclear localization. In summary, we provide evidence that maspin translocates to the nucleus passively. In addition, we identified a peptide in the maspin protein sequence, which is able to drive a 5GFP construct to the nucleus in an energy-dependent manner.

The relationship between nuclear and cytoplasmic ribonucleic acid

1962 ◽  
Vol 156 (962) ◽  
pp. 109-121 ◽  
Keyword(s):  
Suspension Culture ◽  
Hela Cells ◽  
Ribonucleic Acid ◽  
Specific Activity ◽  
Plant Cells ◽  
Stable Form ◽  
Intracellular Pool ◽  
The Individual ◽  
The Relationship

The relationship between nuclear and cytoplasmic ribonucleic acid ( RNA ) was examined in HeLa cells growing exponentially in suspension culture. The cells were exposed to radioactive precursors of RNA and then transferred to non-radioactive medium. Observations were made directly after transfer to non-radioactive medium, when the concentration of radioactive precursors in the intracellular pool was still high, and 12 h later when the concentration of radioactive precursors in the pool was much reduced. The labelled nuclear RNA was separated from the labelled cytoplasmic RNA and the specific activity of the individual bases in both determined. It could be shown (1) that the labelled cytoplasmic RNA was synthesized from acid-soluble precursors by pathways which did not necessarily implicate the labelled nuclear RNA , and (2) that, within the limits of measurement, the labelled nuclear RNA was not transferred to the cytoplasm in a stable form but was rapidly broken down within the cell. The behaviour of the nuclear RNA in multiplying cells is thus seen to be essentially similar to that previously described in non-multiplying cells. In the light of the present findings the available evidence suggests that at least some of the nuclear RNA will prove to be labile in many, if not all, animal and plant cells.

scholarly journals The interactions of ZDHHC5/GOLGA7 with SARS-CoV-2 spike (S) protein and their effects on S protein’s subcellular localization, palmitoylation and pseudovirus entry

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Xiao-Tao Zeng ◽  
Xiao-Ti Yu ◽  
Wei Cheng
Keyword(s):  
Subcellular Localization ◽  
Hela Cells ◽  
Virus Entry ◽  
Affinity Purification ◽  
Cell Types ◽  
Host Protein ◽  
Cysteine Residues ◽  
Host Proteins ◽  
S Protein ◽  
Affinity Purification Mass Spectrometry

Abstract Background Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike (S) protein determines virus entry and the palmitoylation of S protein affects virus infection. An acyltransferase complex ZDHHC5/GOGAL7 that interacts with S protein was detected by affinity purification mass spectrometry (AP-MS). However, the palmitoylated cysteine residues of S protein, the effects of ZDHHC5 or GOLGA7 knockout on S protein’s subcellular localization, palmitoylation, pseudovirus entry and the enzyme for depalmitoylation of S protein are not clear. Methods The palmitoylated cysteine residues of S protein were identified by acyl-biotin exchange (ABE) assays. The interactions between S protein and host proteins were analyzed by co-immunoprecipitation (co-IP) assays. Subcellular localizations of S protein and host proteins were analyzed by fluorescence microscopy. ZDHHC5 or GOGAL7 gene was edited by CRISPR-Cas9. The entry efficiencies of SARS-CoV-2 pseudovirus into A549 and Hela cells were analyzed by measuring the activity of Renilla luciferase. Results In this investigation, all ten cysteine residues in the endodomain of S protein were palmitoylated. The interaction of S protein with ZDHHC5 or GOLGA7 was confirmed. The interaction and colocalization of S protein with ZDHHC5 or GOLGA7 were independent of the ten cysteine residues in the endodomain of S protein. The interaction between S protein and ZDHHC5 was independent of the enzymatic activity and the PDZ-binding domain of ZDHHC5. Three cell lines HEK293T, A549 and Hela lacking ZDHHC5 or GOLGA7 were constructed. Furthermore, S proteins still interacted with one host protein in HEK293T cells lacking the other. ZDHHC5 or GOLGA7 knockout had no significant effect on S protein’s subcellular localization or palmitoylation, but significantly decreased the entry efficiencies of SARS-CoV-2 pseudovirus into A549 and Hela cells, while varying degrees of entry efficiencies may be linked to the cell types. Additionally, the S protein interacted with the depalmitoylase APT2. Conclusions ZDHHC5 and GOLGA7 played important roles in SARS-CoV-2 pseudovirus entry, but the reason why the two host proteins affected pseudovirus entry remains to be further explored. This study extends the knowledge about the interactions between SARS-CoV-2 S protein and host proteins and probably provides a reference for the corresponding antiviral methods.

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