Type

Journal Article

Authors

Yuri Volkov
Dermot Kelleher
Anthony Davies
John F Donegan
Yury P Rakovich
Yurii K Gun'ko
Stephen J Byrne
Jennifer Conroy

Subjects

Biochemistry

Topics
dna protein binding quantum dots chemistry metabolism histones tellurium organelles cadmium telluride cell line rna humans cadmium compounds

CdTe nanoparticles display tropism to core histones and histone-rich cell organelles. (2008)

Abstract The disclosure of the mechanisms of nanoparticle interaction with specific intracellular targets represents one of the key tasks in nanobiology. Unmodified luminescent semiconductor nanoparticles, or quantum dots (QDs), are capable of a strikingly rapid accumulation in the nuclei and nucleoli of living human cells, driven by processes of yet unknown nature. Here, it is hypothesized that such a strong tropism of QDs could be mediated by charge-related properties of the macromolecules presented in the nuclear compartments. As the complex microenvironment encountered by the QDs in the nuclei and nucleoli of live cells is primarily presented by proteins and other biopolymers, such as DNA and RNA, the model of human phagocytic cell line THP1, nuclear lysates, purified protein, and nucleic acid solutions is utilized to investigate the interactions of the QDs with these most abundant classes of intranuclear macromolecules. Using a combination of advanced technological approaches, including live cell confocal microscopy, fluorescent lifetime imaging (FLIM), spectroscopic methods, and zeta potential measurements, it is demonstrated that unmodified CdTe QDs preferentially bind to the positively charged core histone proteins as opposed to the DNA or RNA, resulting in a dramatic shift off the absorption band, and a red shift and decrease in the pholuminescence (PL) intensity of the QDs. FLIM imaging of the QDs demonstrates an increased formation of QD/protein aggregates in the presence of core histones, with a resulting significant reduction in the PL lifetime. FLIM technology for the first time reveals that the localization of negatively charged QDs to their ultimate nuclear and nucleolar destinations dramatically affects the QDs' photoluminescence lifetimes, and offers thereby a sensitive readout for physical interactions between QDs and their intracellular macromolecular targets. These findings strongly suggest that charge-mediated QD/histone interactions could provide the basis for QD nuclear localization downstream of intracellular transport mechanisms.
Collections Ireland -> Trinity College Dublin -> PubMed

Full list of authors on original publication

Yuri Volkov, Dermot Kelleher, Anthony Davies, John F Donegan, Yury P Rakovich, Yurii K Gun'ko, Stephen J Byrne, Jennifer Conroy

Experts in our system

1
Yuri Volkov
Trinity College Dublin
Total Publications: 63
 
2
Dermot Kelleher
Trinity College Dublin
Total Publications: 144
 
3
Anthony Davies
Trinity College Dublin
Total Publications: 27
 
4
John Francis Donegan
Trinity College Dublin
Total Publications: 152
 
5
Yurii K Gun'ko
Trinity College Dublin
Total Publications: 48