Differential effects of distamycin analogues on amplification of human gene sequences by polymerase-chain reaction.
In this report we analyse the effects of distamycin and five distamycin analogues on amplification by polymerase-chain reaction (PCR) of two gene sequences displaying a different A+T/G+C content. The first was a 5' region of the human oestrogen receptor (ER) gene, containing a (TA)26 stretch; the second was a CG-rich sequence of the human Ha-ras oncogene. The results obtained unequivocally demonstrate that the addition of one pyrrole ring significantly improves the ability of distamycin derivatives to interfere with PCR-mediated amplification of the human ER genomic region carrying a (TA)26 stretch. The distamycin analogues analysed differ in the number of pyrrole rings and in the presence of an N-formyl, an N-formimidoyl or a retroamide group at position X1. Among compounds carrying the same number of pyrrole rings, those carrying an N-formyl or an N-formimidoyl group retain a similar inhibitory activity. The retroamide analogues, on the contrary, are much less efficient in inhibiting PCR-mediated amplification of the 5'ER region. With respect to sequence selectivity both distamycin and distamycin analogues exhibit a sequence preference, since they do not inhibit PCR amplification of Ha-ras CG-rich gene regions, with the exception of a distamycin analogue carrying four pyrrole rings.
Passadore
M
M
Department of Biochemistry and Molecular Biology, Ferrara University, Italy.
Bianchi
N
N
Feriotto
G
G
Mischiati
C
C
Giacomini
P
P
Piva
R
R
Gambari
R
R
D001482:Base Composition; D001483:Base Sequence; D001665:Binding Sites; D004247:DNA / Q000737:chemistry; D017931:DNA Primers / Q000737:chemistry; D004214:Distamycins / Q000737:chemistry / Q000494:pharmacology*; D011905:Genes, ras; D066298:In Vitro Techniques; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction / Q000379:methods*; D011960:Receptors, Estrogen / Q000235:genetics
D017931:DNA Primers; D004214:Distamycins; D011960:Receptors, Estrogen; C030000:stallimycin; D004247:DNA