Multi-analyte responsive luminescent probes for the detection of biochemical targets in cell models / Wieloanalitowe, maloczasteczkowe sondy luminescencyjne do symultanicznego wykrywania kilku celów molekularnych w modelach komórkowych.

Luminescence has found wide application in biology, biotechnology and medicine. Particularly, fluorescent and bioluminescent probes allow visualization of molecular targets at the cellular level and even macromolecules or single small-molecule analytes. Among the most reliable tools for visualization of molecular targets are so-called responsive probes, which change the intensity and colour of the emitted signal after interaction with a molecular target. The majority of such probes allow detection of a single analyte. Meanwhile, most of the processes in the human body involve multiple elements. To better understand these mechanisms, it is possible to use several responsive probes simultaneously. However, this poses a risk of their different uptake by cells or different metabolism. In order to provide a more reliable response, so-called multi-analyte and multi-responsive probes are being developed. Examples of such probes will be discussed in the article, divided based on their response mechanism and detected changes within the cell.

Thermodynamic and structural contributions of the 6-thioguanosine residue to helical properties of RNA.

Thionucleotides, especially 4-thiouridine and 6-thioguanosine, are photosensitive molecules that photocrosslink to both proteins and nucleic acids, and this feature is a major reason for their application in various investigations. To get insight into the thermodynamic and structural contributions of 6-thioguanosine to the properties of RNA duplexes a systematic study was performed. In a series of RNA duplexes, selected guanosine residues located in G-C base pairs, mismatches (G-G, G-U, and G-A), or 5' and 3'-dangling ends were replaced with 6-thioguanosine. Generally, the presence of 6-thioguanosine diminishes the thermodynamic stability of RNA duplexes. This effect depends on its position within duplexes and the sequence of adjacent base pairs. However, when placed at a dangling end a 6-thioguanosine residue actually exerts a weak stabilizing effect. Furthermore, the structural effect of 6-thioguanosine substitution appears to be minimal based on NMR and Circular Dichroism (CD) data.

Synthesis and cytotoxic activity of novel acyclic nucleoside analogues with functionality in click chemistry.

We describe synthesis of novel acyclic nucleoside analogues which are building blocks for CuAAC reaction and their activity against two types of human cancer cell lines (HeLa, KB). Three of chosen compounds show promising cytotoxic activity. Synthesis pathway starting from simple and easily accessible substrates employing DMT or TBDPS protective groups is described. Adenosine and thymidine analogues containing alkyne moiety and adenosine analogue containing azido group were synthesized. The obtained units showed ability of forming triazole motif under the CuAAC reaction conditions.

Synthesis and hybridization properties of oligonucleotide analogues with novel acyclic triazole internucleotide linkages.

Herein, we describe synthesis of novel acyclic dinucleotide analogues connected via triazole linkage in CuAAC reaction. Synthesis pathway starting from previously obtained building blocks containing alkyne or azide functional group is described. Further functionalization and application of dinucleotide analogues in DNA phosphoramidite solid-phase synthesis is also explained. Additionally, we have examined the influence of novel modifications on DNA duplex thermodynamic stability.