Nuclear localization of pyrrole–imidazole polyamide–fluorescein conjugates in cell culture

TP Best, BS Edelson, NG Nickols… - Proceedings of the …, 2003 - National Acad Sciences
TP Best, BS Edelson, NG Nickols, PB Dervan
Proceedings of the National Academy of Sciences, 2003National Acad Sciences
A series of hairpin pyrrole–imidazole polyamide–fluorescein conjugates were synthesized
and assayed for cellular localization. Thirteen cell lines, representing 11 human cancers,
one human transformed kidney cell line, and one murine leukemia cell line, were treated
with 5 μM polyamide–fluorescein conjugates for 10–14 h, then imaged by confocal laser
scanning microscopy. A conjugate containing a β-alanine residue at the C terminus of the
polyamide moiety showed no nuclear localization, whereas an analogous compound …
A series of hairpin pyrrole–imidazole polyamide–fluorescein conjugates were synthesized and assayed for cellular localization. Thirteen cell lines, representing 11 human cancers, one human transformed kidney cell line, and one murine leukemia cell line, were treated with 5 μM polyamide–fluorescein conjugates for 10–14 h, then imaged by confocal laser scanning microscopy. A conjugate containing a β-alanine residue at the C terminus of the polyamide moiety showed no nuclear localization, whereas an analogous compound lacking the β-alanine residue was strongly localized in the nuclei of all cell lines tested. The localization profiles of several other conjugates suggest that pyrrole–imidazole sequence and content, dye choice and position, linker composition, and molecular weight are determinants of nuclear localization. The attachment of fluorescein to the C terminus of a hairpin polyamide results in an ≈10-fold reduction in DNA-binding affinity, with no loss of binding specificity with reference to mismatch binding sites.
National Acad Sciences