Author/Editor		Rohozinski, Jan; Hancock, John M.; Keniry, Max A.
Title		Polycytosine regions contained in DNA hairpin loops interact via a four-stranded, parallel structure similar to the i-motif
Type		članek
Vol. and No.		Letnik 22, št. 22
Publication year		1994
Volume		str. 4653-4659
ISSN		0305-1048 - Nucleic acids research
Language		eng
Abstract		Thermal denaturation profiles of an oligodeoxynucleotide that forms a hairpin structure with a cytidine-rich loop show an unexpected transition at 60 degrees C at pH 5.0 but not at pH 8.0. Analytical ultracentrifugation shows that this transition reflects dimer formation via the interaction of loops from two molecules to form a novel structure termed the h-dimer. The dependence of this structure on low pH implies the formation of cytosine-protonated cytosine base pairs. NMR spectroscopy, thermal denaturation and ultraviolet absorption spectral analysis suggest a similarity to the i-motif structure recently proposed for the interaction of deoxycytidine oligomers. The use of hairpin loops to form i-motif-like structures may prove useful in searches for cognate proteins and possibly in the production of antibodies.
Keywords		policitozinske regije zanke DNK vzporedna struktura polycytosine regions DNA hairpin parallel structure