Oligonucleotide Labelling, Conjugation and Affinity Studies

The development of efficient and versatile procedures for attaching reporter groups and other biologically interesting molecules to nucleic acids continues to be an important area of research. Several groups have recently investigated methods that allow reporter molecules to 

A thiol tedio has been utilised fm- the site-specific attachment of rqxnler groups to 175 

Several simple and versatile procedures have been developed for derivatising the 5 -end of oligonucleotides with thiol functions. Attachment of L-cysteine to the S -end of a support-bound oligonucleotide was achieved by activation of the S -hydroxy group with carbonyldi- 

Some potentially exciting studies involving energy transfer from a lumazine chromophore 

A model nucleopeptide (20S) has been prepared which has a phosphodiester bond between 

Oligonucleotide Labelling. Conjugation and Affinity Studies. A review on conjugates of oligonucleotides and related compounds has recently been published. 

The synthesis of 2 -deoxyadenoslne nucleotides which contain an aminoalkyl chain at the 8-posltion covalently attached to fluoroscein and their subsequent incorporation into nucleic acids provides a route to fluorescent DNA probes. 8-(10-Aminodecyl)amino 5 -dAMP was treated with fluoroscein isothiocyanate in aqueous buffer at pH 9 to give the fluoroscelnylated monophosphate in good yield. The labelled triphosphate was most efficiently prepared by an analogous reaction of the phosphoromorpholidate with fluoroscein isothiocyanate 

A universal controlled-pore glass support has been prepared which gives rise to oligonucleotides with a 3 -thiol function after the final deprotection 

Oligodeoxyribonucleotides with sequences 5 -d(GCAC TCAG) (C = 127) and 5 -d(GCACT CAG) (T = 128) have been prepared. The primary amino functions of these oligonucleotides can be reacted specifically with the N-hydroxysuccinimide ester of 4-carboxy-4 -methyl-2,2 -bipyridine and further treatment with Ru(bpy)2(H20)2 gives oligonucleotides which are covalently attached to 

5-[(4-Azidophenacyl)thioJuridine 5 -triphosphate (134) has been prepared by alkylation of 5-thlouridine 5 -triphosphate with 4-azidophenacyl bromide. This analogue is a substrate for E.coli RNA polymerase and once incorporated into RNA can be used to study RNA-protein or RNA-nucleic acids interactions by photo-activated cross-linking. Unlike other photoaffinity labels the cross-linking 

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