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Title: Fluorescent CdSe/ZnS nanocrystal-peptide conjugates for long-term, nontoxic imaging and nuclear targeting in living cells

Abstract

One of the biggest challenges in cell biology is the imaging of living cells. For this purpose, the most commonly used visualization tool is fluorescent markers. However, conventional labels, such as organic fluorescent dyes or green fluorescent proteins (GFP), lack the photostability to allow the tracking of cellular events that happen over minutes to days. In addition, they are either toxic to cells (dyes), or difficult to construct and manipulate (GFP). We report here the use of a new class of fluorescent labels, silanized CdSe/ZnS nanocrystal-peptide conjugates, for imaging the nuclei of living cells. CdSe/ZnS nanocrystals, or so called quantum dots (qdots), are extremely photostable, and have been used extensively in cellular imaging of fixed cells. However, most of the studies about living cells so far have been concerned only with particle entry into the cytoplasm or the localization of receptors on the cell membrane. Specific targeting of qdots to the nucleus of living cells ha s not been reported in previous studies, due to the lack of a targeting mechanism and proper particle size. Here we demonstrate for the first time the construction of a CdSe/ZnS nanocrystal-peptide conjugate that carries the SV40 large T antigen nuclear localization signal (NLS),more » and the transfection of the complex into living cells. By a novel adaptation of commonly used cell transfection techniques for qdots, we were able to introduce and retain the NLS-qdots conjugate in living cells for up to a week without detectable negative cellular effects. Moreover, we can visualize the movement of the CdSe/ZnS nanocrystal-peptide conjugates from cytoplasm to the nucleus, and the accumulation of the complex in the cell nucleus, over a long observation time period. This report opens the door for using qdots to visualize long-term biological events that happen in the cell nucleus, and provides a new nontoxic, long-term imaging platform for cell nuclear processes.« less

Authors:
;
Publication Date:
Research Org.:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org.:
National Aeronautics and Space Administration (US)
OSTI Identifier:
838190
Report Number(s):
LBNL-55719
R&D Project: 862N1A; TRN: US0501264
DOE Contract Number:  
AC03-76SF00098
Resource Type:
Journal Article
Journal Name:
Nano Letters
Additional Journal Information:
Journal Volume: 4; Journal Issue: 10; Other Information: Submitted to Nano Letters: Volume 4, No.10; Journal Publication Date: 10/2004; PBD: 14 Jun 2004
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 60 APPLIED LIFE SCIENCES; 59 BASIC BIOLOGICAL SCIENCES; ANTIGENS; BIOLOGY; CELL MEMBRANES; CONSTRUCTION; CYTOPLASM; DOORS; DYES; NUCLEI; PARTICLE SIZE; PROTEINS; QUANTUM DOTS; QUANTUM DOTS NUCLEAR LOCALIZATION LIVE CELL IMAGING

Citation Formats

Chen, Fanqing, and Gerion, Daniele. Fluorescent CdSe/ZnS nanocrystal-peptide conjugates for long-term, nontoxic imaging and nuclear targeting in living cells. United States: N. p., 2004. Web. doi:10.1021/nl049170q.
Chen, Fanqing, & Gerion, Daniele. Fluorescent CdSe/ZnS nanocrystal-peptide conjugates for long-term, nontoxic imaging and nuclear targeting in living cells. United States. doi:10.1021/nl049170q.
Chen, Fanqing, and Gerion, Daniele. Mon . "Fluorescent CdSe/ZnS nanocrystal-peptide conjugates for long-term, nontoxic imaging and nuclear targeting in living cells". United States. doi:10.1021/nl049170q. https://www.osti.gov/servlets/purl/838190.
@article{osti_838190,
title = {Fluorescent CdSe/ZnS nanocrystal-peptide conjugates for long-term, nontoxic imaging and nuclear targeting in living cells},
author = {Chen, Fanqing and Gerion, Daniele},
abstractNote = {One of the biggest challenges in cell biology is the imaging of living cells. For this purpose, the most commonly used visualization tool is fluorescent markers. However, conventional labels, such as organic fluorescent dyes or green fluorescent proteins (GFP), lack the photostability to allow the tracking of cellular events that happen over minutes to days. In addition, they are either toxic to cells (dyes), or difficult to construct and manipulate (GFP). We report here the use of a new class of fluorescent labels, silanized CdSe/ZnS nanocrystal-peptide conjugates, for imaging the nuclei of living cells. CdSe/ZnS nanocrystals, or so called quantum dots (qdots), are extremely photostable, and have been used extensively in cellular imaging of fixed cells. However, most of the studies about living cells so far have been concerned only with particle entry into the cytoplasm or the localization of receptors on the cell membrane. Specific targeting of qdots to the nucleus of living cells ha s not been reported in previous studies, due to the lack of a targeting mechanism and proper particle size. Here we demonstrate for the first time the construction of a CdSe/ZnS nanocrystal-peptide conjugate that carries the SV40 large T antigen nuclear localization signal (NLS), and the transfection of the complex into living cells. By a novel adaptation of commonly used cell transfection techniques for qdots, we were able to introduce and retain the NLS-qdots conjugate in living cells for up to a week without detectable negative cellular effects. Moreover, we can visualize the movement of the CdSe/ZnS nanocrystal-peptide conjugates from cytoplasm to the nucleus, and the accumulation of the complex in the cell nucleus, over a long observation time period. This report opens the door for using qdots to visualize long-term biological events that happen in the cell nucleus, and provides a new nontoxic, long-term imaging platform for cell nuclear processes.},
doi = {10.1021/nl049170q},
journal = {Nano Letters},
number = 10,
volume = 4,
place = {United States},
year = {2004},
month = {6}
}