title: Ultrastructural localization of F-actin using phalloidin and quantum dots in HL-60 promyelocytic leukemia cell line after cell death induction by arsenic trioxide.
abstract: Quantum dots (QDs) are fluorescent nanocrystals whose unique properties are fundamentally different from organic fluorophores. Moreover, their cores display sufficient electron density to be visible under transmission electron microscopy (TEM). Here, we report a technique for phalloidin-based TEM detection of F-actin. The ultrastructural reorganization of F-actin after arsenic trioxide (ATO) treatment was estimated using a combination of pre- and post-embedding techniques with biotinylated phalloidin and QD-streptavidin conjugates or colloidal gold (AU) conjugated to streptavidin. Ultrastructural studies showed ATO-induced apoptosis of HL-60 cells. Moreover, different patterns of QD-labeled F-actin after ATO treatment were seen. In the case of AU labeling, only a few gold particles were seen and it was impossible to see any difference in F-actin distribution. TEM imaging experiments using QDs and colloidal gold (AU) showed that the strategy of bioconjugation of nanoprobes is the most important factor in biotinylated phalloidin detection of F-actin using streptavidin-coated nanoparticles, especially at the ultrastructural level. Additionally, the results presented in present study confirm the essential role of F-actin in chromatin reorganization during cell death processes.
authors: Department of Histology and Embryology, Nicolaus Copernicus University in Toruń, Collegium Medicum in Bydgoszcz, 24 Karłowicza Street, 85-092 Bydgoszcz, Poland.
authors: Magdalena
authors: M
authors: Izdebska
authors: Maciej
authors: M
authors: Gagat
authors: Dariusz
authors: D
authors: Grzanka
authors: Alina
authors: A
authors: Grzanka
mesh_terms: D000199:Actins / Q000737:chemistry / Q000378:metabolism* / Q000648:ultrastructure; D017209:Apoptosis / Q000187:drug effects*; D000077237:Arsenic Trioxide; D001152:Arsenicals; D018922:HL-60 Cells; D006801:Humans; D015473:Leukemia, Promyelocytic, Acute / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D046529:Microscopy, Electron, Transmission; D010087:Oxides / Q000633:toxicity*; D010590:Phalloidine / Q000737:chemistry*; D045663:Quantum Dots
chemical_list: D000199:Actins; D001152:Arsenicals; D010087:Oxides; D010590:Phalloidine; D000077237:Arsenic Trioxide