Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2001-2-22
pubmed:abstractText
Transfection of the human malaria parasite Plasmodium falciparum is currently performed with circularised plasmids that are maintained episomally in parasites under drug selection but which are rapidly lost when selection pressure is removed. In this paper, we show that in instances where gene targeting is not favoured, transfected plasmids can change to stably replicating forms (SRFs) that are maintained episomally in the absence of drug selection. SRF DNA is a large concatamer of the parental plasmid comprising at least nine plasmids arranged in a head-to-tail array. We show as well that the original unstable replicating forms (URFs) are also present as head-to-tail concatamers, but only comprise three plasmids. Limited digestion and gamma irradiation experiments revealed that while URF concatamers are primarily circular, as expected, SRF concatamers form a more complex structure that includes extensive single-stranded DNA. No evidence of sequence rearrangement or additional sequence was detected in SRF DNA, including in transient replication experiments designed to select for more efficiently replicating plasmids. Surprisingly, these experiments revealed that the bacterial plasmid alone can replicate in parasites. Together, these results imply that transfected plasmids are required to form head-to-tail concatamers to be maintained in parasites and implicate both rolling-circle and recombination-dependent mechanisms in their replication.
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/11160894-10394367, http://linkedlifedata.com/resource/pubmed/commentcorrection/11160894-10613831, http://linkedlifedata.com/resource/pubmed/commentcorrection/11160894-10878256, http://linkedlifedata.com/resource/pubmed/commentcorrection/11160894-1324472, http://linkedlifedata.com/resource/pubmed/commentcorrection/11160894-1779931, http://linkedlifedata.com/resource/pubmed/commentcorrection/11160894-2822257, http://linkedlifedata.com/resource/pubmed/commentcorrection/11160894-2823136, http://linkedlifedata.com/resource/pubmed/commentcorrection/11160894-2959907, http://linkedlifedata.com/resource/pubmed/commentcorrection/11160894-3538420, http://linkedlifedata.com/resource/pubmed/commentcorrection/11160894-383936, http://linkedlifedata.com/resource/pubmed/commentcorrection/11160894-3889657, http://linkedlifedata.com/resource/pubmed/commentcorrection/11160894-6312838, http://linkedlifedata.com/resource/pubmed/commentcorrection/11160894-7041114, http://linkedlifedata.com/resource/pubmed/commentcorrection/11160894-7761856, http://linkedlifedata.com/resource/pubmed/commentcorrection/11160894-781840, http://linkedlifedata.com/resource/pubmed/commentcorrection/11160894-7862676, http://linkedlifedata.com/resource/pubmed/commentcorrection/11160894-8199217, http://linkedlifedata.com/resource/pubmed/commentcorrection/11160894-8571132, http://linkedlifedata.com/resource/pubmed/commentcorrection/11160894-8577727, http://linkedlifedata.com/resource/pubmed/commentcorrection/11160894-8599952, http://linkedlifedata.com/resource/pubmed/commentcorrection/11160894-8692985, http://linkedlifedata.com/resource/pubmed/commentcorrection/11160894-9108483, http://linkedlifedata.com/resource/pubmed/commentcorrection/11160894-9200122, http://linkedlifedata.com/resource/pubmed/commentcorrection/11160894-9380737, http://linkedlifedata.com/resource/pubmed/commentcorrection/11160894-9497038, http://linkedlifedata.com/resource/pubmed/commentcorrection/11160894-9669998
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
1362-4962
pubmed:author
pubmed:issnType
Electronic
pubmed:day
1
pubmed:volume
29
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
716-24
pubmed:dateRevised
2009-11-18
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
An alteration in concatameric structure is associated with efficient segregation of plasmids in transfected Plasmodium falciparum parasites.
pubmed:affiliation
Department of Microbiology and Immunology and the CRC for Vaccine Technology, The University of Melbourne, VIC 3010, Australia.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't