Effect of ecteinascidin-743 on the interaction between DNA binding proteins and DNA31

Marina Bonfanti, Elisa La Valle, José Maria Fernandez Sousa Faro, Glynn Faircloth, Giuseppina Caretti, Roberto Mantovani, Maurizio D'Incalci

Research output: Contribution to journalArticlepeer-review


Ecteinascidin-743 (ET-743) is a tetrahydroisoquinoline alkaloid isolated from Ecteinascidia turbinata, a tunicate growing in mangrove roots in Caribbean. It has been shown to bind in the minor groove of DNA forming covalent adducts by reaction of the N2 of guanine with the carbinolamine moiety. We investigated ET-743 ability to inhibit the binding of different transcription factors to their consensus sequences by using gel shift assays. We have selected three types of factors: (i) oncogene products such as MYC, c-MYB and Maf; (ii) transcriptional activators regulated during the cell cycle as E2F and SRF; and (iii) general transcription factors such as TATA binding protein (TBP), Sp1 and NF-Y, We observed no inhibition of the binding of Sp1, Maf, MYB and MYC. Inhibition of DNA binding was observed for TBP, E2F, SRF at ET-743 concentrations ranging from 50 to 300 μM. The inhibition of binding of NF-Y occurs at even lower concentrations (i.e. 10-30 μM) when the recombinant subunits of NF-Y are preincubated with the drug, indicating that the inhibition of NF-Y binding does not require previous ET-743 DNA binding. Since NF-Y is a trimer containing two subunits with high resemblance to histones H2B and H2A, we have investigated the effect of ET-743 on nucleosome reconstitution. ET-743 caused a decrease of the nucleosomal band at 100 nM, with the complete disappearance of the band at 3-10 μM. These data suggest that the mode of action of this novel anticancer drug is related to its ability to modify the interaction between some DNA binding proteins and DNA.

Original languageEnglish
Pages (from-to)179-186
Number of pages8
JournalAnti-Cancer Drug Design
Issue number3
Publication statusPublished - Jun 1999


  • Ecteinascidin-743
  • Histones
  • Minor groove
  • Natural product
  • Transcription factors

ASJC Scopus subject areas

  • Drug Discovery
  • Organic Chemistry
  • Oncology
  • Biochemistry, Genetics and Molecular Biology(all)
  • Biochemistry
  • Pharmacology


Dive into the research topics of 'Effect of ecteinascidin-743 on the interaction between DNA binding proteins and DNA31'. Together they form a unique fingerprint.

Cite this