scholarly journals Mitotic Golgi clusters are not tubular endosomes

1993 ◽  
Vol 104 (3) ◽  
pp. 811-818 ◽  
Author(s):  
M. Pypaert ◽  
T. Nilsson ◽  
E.G. Berger ◽  
G. Warren

HeLa cells were incubated with 15 nm BSA-gold for 1 or 2 hours to mark the endocytic pathway and mitotic cells were then isolated by shake-off. Thin, frozen sections were labelled with antibodies against two resident Golgi markers, beta-(1,4)-galactosyltransferase and N-acetylglucosaminyltransferase I. Detection of the latter was aided by the use of a HeLa cell line stably expressing a myc-tagged version of the endogenous protein. The secondary antibodies were coupled to either 5 or 10 nm gold so that the distribution of each of the three markers could be followed. Qualitative and quantitative studies showed that there were two populations of clusters, those described by us earlier and termed Golgi clusters (Lucocq et al. (1987) J. Cell Biol. 104, 865–874), containing either or both Golgi markers, and clusters of tubular endosomes containing BSA-gold. There was very little overlap showing that Golgi clusters cannot be tubular endosomes as concluded by Tooze and Hollinshead (1992) Eur. J. Cell Biol. 58, 228–242.

1993 ◽  
Vol 120 (1) ◽  
pp. 5-13 ◽  
Author(s):  
T Nilsson ◽  
M Pypaert ◽  
M H Hoe ◽  
P Slusarewicz ◽  
E G Berger ◽  
...  

Thin, frozen sections of a HeLa cell line were double labeled with specific antibodies to localize the trans-Golgi enzyme, beta 1,4 galactosyltransferase (GalT) and the medial enzyme, N-acetylglucosaminyltransferase I (NAGT I). The latter was detected by generating a HeLa cell line stably expressing a myc-tagged version of the endogenous protein. GalT was found in the trans-cisterna and trans-Golgi network but, contrary to expectation, NAGT I was found both in the medial- and trans-cisternae, overlapping the distribution of GalT. About one third of the NAGT I and half of the GalT were found in the shared, trans-cisterna. These data show that the differences between cisternae are determined not by different sets of enzymes but by different mixtures.


2020 ◽  
Vol 16 ◽  
Author(s):  
Jamshed Iqbal ◽  
Ayesha Basharat ◽  
Sehrish Bano ◽  
Syed Mobasher Ali Abid ◽  
Julie Pelletier ◽  
...  

Aims: The present study was conducted to examine the inhibitory effects of synthesized sulfonylhydrazones on the expression of CD73 (ecto-5′-NT). Background: CD73 (ecto-5′-NT) represents the most significant class of ecto-nucleotidases which are mainly responsible for dephosphorylation of adenosine monophosphate to adenosine. Inhibition of CD73 played an important role in the treatment of cancer, autoimmune disorders, precancerous syndromes, and some other diseases associated with CD73 activity. Objective: Keeping in view the significance of CD73 inhibitor in the treatment of cervical cancer, a series of sulfonylhydrazones (3a-3i) derivatives synthesized from 3-formylchromones were evaluated. Methods: All sulfonylhydrazones (3a-3i) were evaluated for their inhibitory activity towards CD73 (ecto-5′-NT) by the malachite green assay and their cytotoxic effect was investigated on HeLa cell line using MTT assay. Secondly, most potent compound was selected for cell apoptosis, immunofluorescence staining and cell cycle analysis. After that, CD73 mRNA and protein expression were analyzed by real-time PCR and Western blot. Results: Among all compounds, 3h, 3e, 3b, and 3c were found the most active against rat-ecto-5′-NT (CD73) enzyme with IC50 (µM) values of 0.70 ± 0.06 µM, 0.87 ± 0.05 µM, 0.39 ± 0.02 µM and 0.33 ± 0.03 µM, respectively. These derivatives were further evaluated for their cytotoxic potential against cancer cell line (HeLa). Compound 3h and 3c showed the cytotoxicity at IC50 value of 30.20 ± 3.11 µM and 86.02 ± 7.11 µM, respectively. Furthermore, compound 3h was selected for cell apoptosis, immunofluorescence staining and cell cycle analysis which showed promising apoptotic effect in HeLa cells. Additionally, compound 3h was further investigated for its effect on expression of CD73 using qRT-PCR and western blot. Conclusion: Among all synthesized compounds (3a-3i), Compound 3h (E)-N'-((6-ethyl-4-oxo-4H-chromen-3-yl) methylene)-4-methylbenzenesulfonohydrazide was identified as most potent compound. Additional expression studies conducted on HeLa cell line proved that this compound successfully decreased the expression level of CD73 and thus inhibiting the growth and proliferation of cancer cells.


Author(s):  
Ying Qian ◽  
Yingnian Yu ◽  
Xingruo Cheng ◽  
Jianhong Luo ◽  
Haiyang Xie ◽  
...  

2021 ◽  
pp. 1-18
Author(s):  
Barbara L. Voss

This article is the second in a two-part series that analyzes current research on harassment in archaeology. Both qualitative and quantitative studies, along with activist narratives and survivor testimonials, have established that harassment is occurring in archaeology at epidemic rates. These studies have also identified key patterns in harassment in archaeology that point to potential interventions that may prevent harassment, support survivors, and hold perpetrators accountable. This article reviews five key obstacles to change in the disciplinary culture of archaeology: normalization, exclusionary practices, fraternization, gatekeeping, and obstacles to reporting. Two public health paradigms—the social-environmental model and trauma-informed approaches—are used to identify interventions that can be taken at all levels of archaeological practice: individual, relational, organizational, community, and societal.


RSC Advances ◽  
2017 ◽  
Vol 7 (9) ◽  
pp. 5282-5296 ◽  
Author(s):  
Marija S. Jeremić ◽  
Hubert Wadepohl ◽  
Vesna V. Kojić ◽  
Dimitar S. Jakimov ◽  
Ratomir Jelić ◽  
...  

Two new Rh(iii)–ed3a complexes [Rh(ed3a)(OH2)]·H2O and Na[Rh(ed3a)Cl]·H2O have shown good antitumor activity, especially against HeLa cell line.


2018 ◽  
Author(s):  
◽  
Kola Augustus Oluwafemi

This work focuses on the design, synthesis and evaluation of imine-containing heterocyclic and acyclic compounds with special focus on their bioactivity against parasitic protozoans (P. falciparum and T. brucei) - given the context of drug resistance in the treatment of malaria and Human African sleeping sickness and the fact that several bioactive organic compounds have been reported to possess the imino group. Starting from 2-aminopyridine, novel #-alkylated-5-bromo-7-azabenzimidazoles and substituted 5-bromo-1-(carbamoylmethy)-7-azabenzimidazole derivatives were prepared, and their bioactivity against parasitic protozoans was assessed. NMR spectra of the substituted 5- bromo-1-(carbamoylmethy)-7-azabenzimidazole derivatives exhibited rotational isomerism, and a dynamic NMR study was used in the estimation of the rate constants and the free- energies of activation for rotation. The free-energy differences between the two rotamers were determined and the more stable conformations were predicted. Novel 2-phenyl-7-azabenzimidazoles were also synthesised from 2-aminopyridine. A convenient method for the regioselective formylation of 2,3-diaminopyridines into 2-amino- 7-(benzylimino)pyridine analogues of 2-phenyl-7-azabenzimidazole was developed, and some of the resulting imino derivatives were hydrogenated to verify the importance of the imino moiety for bioactivity. The 2-phenyl-7-azabenzimidazoles and the 2-amino-7- (benzylimino)pyridine analogues were screened for their anti-protozoal activity and their cytotoxicity level was determined against the HeLa cell line. In order to validate the importance of the pyridine moiety, novel #-(phenyl)-2- hydroxybenzylimines, #-(benzyl)-2-hydroxybenzylimines and (±)-trans-1,2-bis[2- hydroxybenzylimino]cyclohexanes were also synthesized and screened for activity against the parasitic protozoans and for cytotoxicity against the HeLa cell line. The biological assay results indicated that these compounds are not significantly cytotoxic and a good number of them show potential as lead compounds for the development of new malaria and trypanosomiasis drugs.


Sign in / Sign up

Export Citation Format

Share Document