Fluorophores labeling between nucleotides

When the nucleotides are labeled with different fluorophores, they are identified by their spectral characteristics. Alternatively, the same fluorophore can be used and distinction is made on the basis of different lifetimes as a result of different interactions between the nucleotide and the fluorophore. 

A method for the detection of single base mismatches (single nucleotide polymorphism, SNPs) with DNA microarrays is described that does not require labelling of the sample DNA. The method is based on the disruption of FRET between a fluorophore attached to the immobilised probe, and a quencher sequence complementary except for an artificial mismatch. Typically, a universal... 

Elucidation of the thermodynamic basis of Rab membrane targeting requires analysis of interaction between prenylated Rab proteins (GDP/GTP-bound) and REP/GDI. Such analysis is made possible by generation of fluorescent labelled prenylated Rab proteins (Scheme 10a) [30, 54]. A series of Rab7-based protein probes with one or two isoprenyl moieties and fluorophores on the lipid moiety or the lysine side chain were prepared using the EPL technique. The semisynthetic method enables precise installation of GDP/GTP into Rab proteins to generate the off and on states, yielding for the first time homogeneous preparations of functionalized prenylated proteins in a well-defined nucleotide bound state [87]. 

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