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Related to episome: endogenote, episomal DNA


A segment of DNA in certain cells, especially bacterial cells, that can exist either autonomously in the cytoplasm or as part of a chromosome.

ep′i·so′mal adj.
ep·i·so′mal·ly adv.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(Microbiology) a unit of genetic material (DNA) in bacteria, such as a plasmid, that can either replicate independently or can be integrated into the host chromosome
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˈɛp əˌsoʊm)

a strand of DNA that is extrachromosomal, as a bacterial plasmid.
[< French épisome (1958); see epi-, -some3]
ep`i•so′mal, adj.
ep`i•so′mal•ly, adv.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.episome - DNA that is not incorporated into the genome but is replicated together with the genome (especially in bacterial cells)
deoxyribonucleic acid, desoxyribonucleic acid, DNA - (biochemistry) a long linear polymer found in the nucleus of a cell and formed from nucleotides and shaped like a double helix; associated with the transmission of genetic information; "DNA is the king of molecules"
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
References in periodicals archive ?
These results indicates that Integration of HPV16 more common than episome genome in the host genome.
Lipkin, "Bocavirus episome in infected human tissue contains Non- Identical termini," PLoS ONE, vol.
The linking regions of EBNA1 LR1 and LR2 were revealed to have a strong preference for G-quadruplex RNA and it was revealed that G-quadruplex RNA-interacting drugs block the functions of EBNA1 that are critical for viral DNA replication and episome maintenance [12,13].
During latency, a limited number of viral genes are expressed which maintain the viral episome [86, 87].
These vectors are based on a well-established technology in which the inclusion of the EBNA1 gene and the OriP sequence of the Epstein-Barr virus allow a plasmid, after a single transfection, to replicate extrachromosomally, as a circular episome, in several cell types [45].
Unlike HPV and HBV, EBV genome is not integrated into the host genome but maintained as an episome inside latently infected cells [33, 35].
This approach is simple and fast and will greatly improve the way we study Leishmania genes compared to previous methods of gene tagging (e.g., by expressing GOI fused to a fluorescent tag from an episome), since part of their endogenous regulation may be better maintained through the conservation of either the 5' or 3'UTR (depending whether the tagging is at the Cor N-terminus, resp.).
The cccDNA episome is the transcriptional template for HBV messenger RNA transcripts that encode viral structural and NS proteins and the pregenomic RNA template for reverse transcription and synthesis of the viral genome [5].
In HPV-associated malignancies, high-risk HPV DNA may either be integrated within the cellular genome or it may be maintained as an episome in the nuclei of the malignant cells.
As described previously [36], rKSHV.219 expresses enhanced green fluorescent protein (GFP) under the control of the strong cellular elongation factor 1-[alpha] promoter and the Ds-red fluorescent protein (RFP) from the KSHV lytic polyadenylated nuclear (PAN) RNA promoter, in addition to the gene for puromycin resistance as a selectable marker for maintenance of the viral episome in rKSHV.219-infected cells [36].