Protein-RNA interactions play important biological roles and hence reactive RNA probes for cross-linking with proteins are important tools in their identification and study. To this end, we designed and synthesized 5'-O-triphosphates bearing a reactive squaramate group attached to position 5 of cytidine or position 7 of 7-deazaadenosine and used them as substrates for polymerase synthesis of modified RNA. In vitro transcription with T7 RNA polymerase or primer extension using TGK polymerase was used for synthesis of squaramate-modified RNA probes which underwent covalent bioconjugations with amine-linked fluorophore and lysine-containing peptides and proteins including several viral RNA polymerases or HIV reverse transcriptase. Inhibition of RNA-depending RNA polymerases from Japanese Encephalitis virus was observed through formation of covalent cross-link which was partially identified by MS/MS analysis. Thus, the squaramate-linked NTP analogs are useful building blocks for the synthesis of reactive RNA probes for bioconjugations with primary amines and cross-linking with lysine residues.

• Publikační typ
• časopisecké články MeSH

Reactive RNA probes are useful for studying and identifying RNA-binding proteins. To that end, we designed and synthesized chloroacetamide-linked 7-deaza-ATP which was a good substrate for T7 RNA polymerase in in vitro transcription assay to synthesize reactive RNA probes bearing one or several reactive modifications. Modified RNA probes reacted with thiol-containing molecules as well as with cysteine- or histidine-containing peptides to form stable covalent products. They also reacted selectively with RNA-binding proteins to form cross-linked conjugates in high conversions thanks to proximity effect. Our modified nucleotide and RNA probes are promising tools for applications in RNA (bio)conjugations or RNA proteomics.

• Klíčová slova
• Bioconjugations, Cross-Linking, Modified RNA, Proteins, RNA Polymerases,
• MeSH
• DNA řízené RNA-polymerasy metabolismus   MeSH
• DNA metabolismus   MeSH
• nukleotidy * metabolismus   MeSH
• proteiny vázající RNA MeSH
• reagencia zkříženě vázaná MeSH
• RNA sondy MeSH
• RNA * MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• chloroacetamide MeSH Prohlížeč
• DNA řízené RNA-polymerasy MeSH
• DNA MeSH
• nukleotidy * MeSH
• proteiny vázající RNA MeSH
• reagencia zkříženě vázaná MeSH
• RNA sondy MeSH
• RNA * MeSH

Linear or branched 1,3-diketone-linked thymidine 5'-O-mono- and triphosphate were synthesized through CuAAC click reaction of diketone-alkynes with 5-azidomethyl-dUMP or -dUTP. The triphosphates were good substrates for KOD XL DNA polymerase in primer extension synthesis of modified DNA. The nucleotide bearing linear 3,5-dioxohexyl group (HDO) efficiently reacted with arginine-containing peptides to form stable pyrimidine-linked conjugates, whereas the branched 2-acetyl-3-oxo-butyl (PDO) group was not reactive. Reaction with Lys or a terminal amino group formed enamine adducts that were prone to hydrolysis. This reactive HDO modification in DNA was used for bioconjugations and cross-linking with Arg-containing peptides or proteins (e.g. histones).

• Klíčová slova
• DNA polymerases, bioconjugations, cross-linking reactions, nucleotides, proteins,
• MeSH
• arginin chemie   MeSH
• DNA chemická syntéza   chemie   MeSH
• histony chemie   MeSH
• ketony chemická syntéza   chemie   MeSH
• nádorový supresorový protein p53 chemie   MeSH
• peptidy chemie   MeSH
• proteiny chemie   MeSH
• reagencia zkříženě vázaná chemická syntéza   chemie   MeSH
• sérový albumin hovězí chemie   MeSH
• skot MeSH
• thiminnukleotidy chemická syntéza   chemie   MeSH
• zvířata MeSH
• Check Tag
• skot MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• arginin MeSH
• DNA MeSH
• histony MeSH
• ketony MeSH
• nádorový supresorový protein p53 MeSH
• peptidy MeSH
• proteiny MeSH
• reagencia zkříženě vázaná MeSH
• sérový albumin hovězí MeSH
• thiminnukleotidy MeSH