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Updated: Feb 17, 2026

Chemical Triphosphorylation of Oligonucleotides
Published on: June 2, 2022
Human cyclic nucleotide phosphodiesterases possess a much broader substrate-specificity than previously appreciated
Daniel Reinecke1, Heike Burhenne, Peter Sandner
1Institute of Pharmacology, Medical School of Hannover, Hannover, Germany.
Abstract:
Phosphodiesterases (PDEs) capable of degrading cAMP and cGMP are indispensable for the regulation of cyclic nucleotide-mediated signals. The existence of other cyclic nucleotides such as cCMP and cUMP has been discussed controversially in the literature. Despite publications on PDEs hydrolyzing cCMP or cUMP, the molecular identity of such enzymes remained elusive. Recently, we have provided evidence for a role of cCMP as second messenger in vascular relaxation and inhibition of platelet aggregation. Using an HPLC-MS based assay, here, we show that human PDEs belonging to various families hydrolyze not only cAMP and cGMP but also other cyclic nucleotides.
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