Scaffolding along nucleic acid duplexes using 2'-amino-locked nucleic acids.

CONSPECTUS: Incorporation of chemically modified nucleotide scaffolds into nucleic acids to form assemblies rich in function is an innovative area with great promise for nanotechnology and biomedical and material science applications. The intrinsic biorecognition potential of nucleic acids combined with advanced properties of the locked nucleic acids (LNAs) provide opportunities to develop new nanomaterials and devices like sensors, aptamers, and machines. In this Account, we describe recent research on preparation and investigation of the properties of LNA/DNA hybrids containing functionalized 2'-amino-LNA nucleotides.

"Clickable" LNA/DNA probes for fluorescence sensing of nucleic acids and autoimmune antibodies.

Herein we describe fluorescent oligonucleotides prepared by click chemistry between novel alkyne-modified locked nucleic acid (LNA) strands and a series of fluorescent azides for homogeneous (all-in-solution) detection of nucleic acids and autoimmune antibodies.

Rapid genotyping using pyrene-perylene locked nucleic acid complexes.

We have developed an assay for single strand DNA and RNA detection which is based on novel pyrene-perylene FRET pairs attached to short LNA/DNA probes. The assay is based on ratiometric emission upon binding of target DNA/RNA by three combinations of fluorescent LNA/DNA reporter strands. Specific geometry of the pyrene fluorophore attached to the 2'-amino group of 2'-amino-LNA in position 4 allows for the first time to efficiently utilize dipole-dipole orientation parameter for sensing of single-nucleotide polymorphisms (SNPs) in nucleic acid targets by FRET.

Peptide-LNA oligonucleotide conjugates.

Although peptide-oligonucleotide conjugates (POCs) are well-known for nucleic acids delivery and therapy, reports on internal attachment of peptides to oligonucleotides are limited in number. To develop a convenient route for preparation of internally labeled POCs with improved biomedical properties, peptides were introduced into oligonucleotides via a 2'-alkyne-2'-amino-LNA scaffold. Derivatives of methionine- and leucine-enkephalins were chosen as model peptides of mixed amino acid content, which were singly and doubly incorporated into LNA/DNA strands using highly efficient copper(i)-catalyzed azide-alkyne cycloaddition (CuAAC) "click" chemistry.

A locked nucleic acid-based nanocrawler: designed and reversible movement detected by multicolor fluorescence.

Herein we introduce a novel fluorescent LNA/DNA machine, a nanocrawler, which reversibly moves along a directionally polar complementary road controlled by affinity-enhancing locked nucleic acid (LNA) monomers and additional regulatory strands. Polyaromatic hydrocarbon (PAH) dyes attached to 2'-amino-LNA monomers are incorporated at four stations of the system, enabling simple detection of the position of the nanocrawler via a step-specific color signal. The sensing is provided by highly sensitive, chemically stable, and photostable PAH LNA interstrand communication systems, including pyrene excimer formation and pyrene-perylene interstrand Förster resonance energy transfer.