Linked Life Data

203402

Source:http://linkedlifedata.com/resource/pubmed/id/203402

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1978-4-26
pubmed:abstractText
We have investigated by electron microscopy the mechanism of DNA compaction and have found that the double helix has the intrinsic potential to direct its own packaging into two distinctly different and mutally exclusive modes. The mode of DNA packaging is determined by the electrostatic charge density and water activity of the immediate microenvironment of the helix. The two basic structures formed by both linear and covalently closed-circular DNA are: a left-handed supercoil characteristic of minimally charge-shielded DNA, and a smooth rod characteristic of fully charge-shielded DNA. We propose that in the supercoil, the double helix is overwound (increased turn-angle), while in the rod, the helix is folded back and forth on itself. Variation of these two basic structures are the beaded fiber of DNA obtained with partially charge-shielded DNA and the toroid formed by the bending of the DNA rod and fusion of its ends in the presence of certain cations. We compare the DNA packaging inside these in vitro generated structures to DNA packaging in chromatin and viral capsids, and conclude that the packaging of DNA brought about by the use of salts and alcohol closely mimics the packaging behavior of the DNA in vivo, where it is usually complexed with histones or polyamines.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0092-8674
pubmed:author
pubmed:issnType
Print
pubmed:volume
13
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
295-306
pubmed:dateRevised
2006-5-1
pubmed:meshHeading
pubmed:year
1978
pubmed:articleTitle
The compaction of DNA helices into either continuous supercoils or folded-fiber rods and toroids.
pubmed:publicationType
Journal Article