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PubMed · 6572358

Wrinkled DNA.

S Arnott·R Chandrasekaran·L C Puigjaner·J K Walker·I H Hall·D L Birdsall·R L Ratliff
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Abstract

The B form of poly d(GC):poly d(GC) in orthorhombic microcrystallites in oriented fibers has a secondary structure in which a dinucleotide is the repeated motif rather than a mononucleotide as in standard, smooth B DNA. One set of nucleotides (probably GpC) has the same conformations as the smooth form but the alternate (CpG) nucleotides have a different conformation at C3'-O3'. This leads to a distinctive change in the orientation of the phosphate groups. Similar perturbations can be detected in other poly d(PuPy):poly d(PuPy) DNAs such as poly d(IC):poly d(IC) and poly d(AT):poly d(AT) in their D forms which have tetragonal crystal environments. This suggests that such perturbations are intrinsic to all stretches of duplex DNA where purines and pyrimidines alternate and may play a role in the detection and exploitation of such sequences by regulatory proteins.

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DNADinucleoside PhosphatesModels, MolecularNucleic Acid ConformationOligonucleotidesPolydeoxyribonucleotidesStructure-Activity RelationshipX-Ray DiffractionComparative StudyJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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S Arnott, R Chandrasekaran, L C Puigjaner, J K Walker, I H Hall, D L Birdsall, R L Ratliff. 1983-03-11. Wrinkled DNA.. https://doi.org/10.1093/nar%2F11.5.1457

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