Homologous pairing of DNA molecules by Ustilago rec1 protein is promoted by sequences of Z-DNA.

TitleHomologous pairing of DNA molecules by Ustilago rec1 protein is promoted by sequences of Z-DNA.
Publication TypeJournal Article
Year of Publication1986
AuthorsKmiec EB, Holloman WK
JournalCell
Volume44
Issue4
Pagination545-54
Date Published1986 Feb 28
ISSN0092-8674
KeywordsAntigen-Antibody Complex, Base Sequence, DNA, Superhelical, Exodeoxyribonuclease V, Fungal Proteins, Hydrogen Bonding, Nucleic Acid Conformation, Plasmids, Recombination, Genetic, Sequence Homology, Nucleic Acid, Structure-Activity Relationship, Ustilago
Abstract

Plasmids containing Z-DNA stretches can be paired and linked by combined action of Ustilago rec1 protein and topoisomerase. The product formed is a hemicatenated dimer in which two DNA rings are topologically intertwined at a region of homology. Superhelicity governs the reaction. Formation of linked product is coupled with formation of Z-DNA in the plasmid, a process dependent on the superhelix density. Pairing appears to initiate within the Z-DNA sequence, not at the unwound B-Z junction. The reaction can be blocked by a Z-DNA-specific binding protein, namely Z-DNA antibody. Plasmids with alternating Z-DNA dG-dC sequences at different sites on otherwise homologous molecules can be linked at the dG-dC sequences. However, a plasmid with a (dG-dC)n.(dG-dC)n Z-DNA stretch cannot be linked with a plasmid containing a (dG-dT)n.(dC-dA)n Z-DNA stretch.

Alternate JournalCell
PubMed ID3948243
Grant ListGM27103 / GM / NIGMS NIH HHS / United States

Weill Cornell Medicine Microbiology and Immunology 1300 York Avenue, Box 62 New York, NY 10065 Phone: (212) 746-6505 Fax: (212) 746-8587