Structural isomers of bis-PNA bound to a target in duplex DNA

Citation
Gi. Hansen et al., Structural isomers of bis-PNA bound to a target in duplex DNA, J MOL BIOL, 307(1), 2001, pp. 67-74
Citations number
28
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Molecular Biology & Genetics
Journal title
JOURNAL OF MOLECULAR BIOLOGY
ISSN journal
0022-2836 → ACNP
Volume
307
Issue
1
Year of publication
2001
Pages
67 - 74
Database
ISI
SICI code
0022-2836(20010316)307:1<67:SIOBBT>2.0.ZU;2-T
Abstract
Upon binding of a decamer bis-PNA (H-Lys-TTCCTCTCTT-(eg1)(3)-TTCTCTCCTT-Lys NH(2)) to a complementary target in a double-stranded DNA fragment, three d istinct complexes were detected by gel mobility shift analysis. Using in si tu chemical probing techniques (KMnO4 and DMS) it was found that all three complexes represent bona fide sequence-specific PNA binding to the designat ed target, bur the complexes were structurally different. One complex that preferentially formed at higher FNA concentrations contains two bis-PNA mol ecules per DNA target, whereas the other two complexes are genuine tripler invasion clamped structures. However, these two latter complexes differ by the path relative to the DNA target of the flexible ethylene-glycol linker connecting the two PNA oligomers that comprise a bis-PNA. We distinguish be tween one in which the linker wraps around the non-target DNA strand, thus making this strand part of the tripler invasion complex and another complex that encompass the target strand only. The implications of these results a re discussed in terms of DNA targeting by synthetic ligands. (C) 2001 Acade mic Press.