title: N7-platinated ribonucleotides are not incorporated by RNA polymerases. New perspectives for a rational design of platinum antitumor drugs.
abstract: In this work, we assessed the capacity of RNA polymerases to use platinated ribonucleotides as substrates for RNA synthesis by testing the incorporation of the model compound [Pt(dien)(N7-5'-GTP)] (dien=diethylenetriamine; GTP=5'-guanosine triphosphate) into a natural RNA sequence. The yield of in vitro transcription operated by T7 RNA polymerase, on the LacZ (Escherichia coli gene encoding for β-galactosidase) sequence, decreases progressively with decreasing the concentration of natural GTP, in favor of the platinated nucleotide, [Pt(dien)(N7-5'-GTP)]. Comparison of the T7 RNA polymerase transcription activities for [Pt(dien)(N7-5'-GTP)] compound incorporation reaction test, with respect to the effect of a decreasing concentration of natural GTP, showed no major differences. A specific inhibitory effect of compound [Pt(dien)(N7-5'-GTP)] (which may pair the complementary base on the DNA strand, without being incorporated in the RNA by the T7 RNA polymerase) was evidenced. Our findings therefore suggest that RNA polymerases, unlike DNA polymerases, are unable to incorporate N7-platinated nucleotides into newly synthesized nucleic acids. In this respect, specifically designed N7-platinated nucleotides based compounds could be used in alternative to the classical platinum based drugs. This approach may offer a possible strategy to target specifically DNA, without affecting RNA, and is potentially able to better modulate pharmacological activity.
authors.affiliation: Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali, Università del Salento, Via Monteroni, I-73100 Lecce, Italy. Electronic address: michele.benedetti@unisalento.it.
authors.forename: Michele
authors.initials: M
authors.lastname: Benedetti
authors.affiliation: Neuropathology Unit, Institute of Experimental Neurology and Division of Neuroscience, IRCCS San Raffaele Scientific Institute, via Olgettina 60, 20132 Milan, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Romano
authors.affiliation: Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali, Università del Salento, Via Monteroni, I-73100 Lecce, Italy.
authors.forename: Federica
authors.initials: F
authors.lastname: De Castro
authors.affiliation: Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali, Università del Salento, Via Monteroni, I-73100 Lecce, Italy.
authors.forename: Chiara R
authors.initials: CR
authors.lastname: Girelli
authors.affiliation: Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali, Università del Salento, Via Monteroni, I-73100 Lecce, Italy.
authors.forename: Daniela
authors.initials: D
authors.lastname: Antonucci
authors.affiliation: Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali, Università del Salento, Via Monteroni, I-73100 Lecce, Italy.
authors.forename: Danilo
authors.initials: D
authors.lastname: Migoni
authors.affiliation: Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali, Università del Salento, Via Monteroni, I-73100 Lecce, Italy.
authors.forename: Tiziano
authors.initials: T
authors.lastname: Verri
authors.affiliation: Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali, Università del Salento, Via Monteroni, I-73100 Lecce, Italy. Electronic address: fp.fanizzi@unisalento.it.
authors.forename: Francesco P
authors.initials: FP
authors.lastname: Fanizzi
mesh_terms: D000970:Antineoplastic Agents / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D004269:DNA, Bacterial / Q000737:chemistry / Q000378:metabolism; D012321:DNA-Directed RNA Polymerases / Q000737:chemistry / Q000378:metabolism; D015195:Drug Design; D004926:Escherichia coli / Q000737:chemistry / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000096:biosynthesis; D007763:Lac Operon; D009944:Organoplatinum Compounds / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D012329:RNA, Bacterial / Q000096:biosynthesis / Q000737:chemistry; D012265:Ribonucleotides / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D014764:Viral Proteins / Q000737:chemistry / Q000378:metabolism
chemical_list: D000970:Antineoplastic Agents; D004269:DNA, Bacterial; D029968:Escherichia coli Proteins; D009944:Organoplatinum Compounds; D012329:RNA, Bacterial; D012265:Ribonucleotides; D014764:Viral Proteins; C062210:bacteriophage T7 RNA polymerase; D012321:DNA-Directed RNA Polymerases
keywords: Antitumor drug; Cisplatin; DNA; Metalated purine; RNA