Which hybridization technique uses fluorophore-tagged oligonucleotides?
Fluorescence In Situ Hybridization employs short oligonucleotide probes covalently conjugated with fluorophores such as FITC, Cy3, or Texas Red that hybridize specifically to complementary DNA or RNA sequences in fixed chromosomes, interphase nuclei, or tissue sections. Hybridization signal visualizes genomic loci, copy number alterations, translocations, or gene expression patterns under fluorescence microscopy. SPR detects refractive index shifts, electrophoretic mobility shift assay evaluates protein-DNA binding by gel retardation, and ROTA assesses transcription rate. FISH combines molecular hybridization specificity with fluorescence detection providing spatial resolution in cytogenetics research.
Ref: NCERT Biology Class XII Principles on Klenow fill-in labeling, Lehninger Chapter 9 DNA cloning techniques, and Molecular Cloning by Sambrook Chapter 10 documenting end-labeling of cohesive termini.