小円、小環状の、ミニサークル

Wikipedia preview

出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2016/04/30 11:25:58」(JST)

wiki en

Minicircle preparation from a parental plasmid. The parental plasmid contains two recombinase target sites (black half arrows). Recombination between these sites generates the desired minicircle (bottom right) together with the miniplasmid (bottom left). The hook on the red minicircle-insert stands for a scaffold-matrix attachment region ( S/MAR-Element), which allows for autonomous replication in the recipient cell.

Minicircles are small (~4kb) circular plasmid derivatives that have been freed from all prokaryotic vector parts. They have been applied as transgene carriers for the genetic modification of mammalian cells, with the advantage that, since they contain no bacterial DNA sequences, they are less likely to be perceived as foreign and destroyed. (Typical transgene delivery methods involve plasmids, which contain foreign DNA.) The smaller size of minicircles also extends their cloning capacity and facilitates their delivery into cells.

Their preparation usually follows a two-step procedure:^[1] ^[2]

production of a ´parental plasmid´ (bacterial plasmid with eukaryotic inserts) in 'E. coli'
induction of a site-specific recombinase at the end of this process but still in bacteria. These steps are followed by the
- excision of prokaryotic vector parts via two recombinase-target sequences at both ends of the insert
- recovery of the resulting minicircle (vehicle for the highly efficient modification of the recipient cell) and the miniplasmid by capillary gel electrophoresis (CGE)

The purified minicircle can be transferred into the recipient cell by transfection or lipofection and into a differentiated tissue by, for instance, jet injection.

Conventional minicircles lack an origin of replication, so they do not replicate within the target cells and the encoded genes will disappear as the cell divides (which can be either an advantage or disadvantage depending on whether the application demands persistent or transient expression). A novel addition to the field are nonviral self-replicating minicircles, which owe this property to the presence of a S/MAR-Element. Self-replicating minicircles hold great promise for the systematic modification of stem cells and will significantly extend the potential of their plasmidal precursor forms ("parental plasmids"), the more as the principal feasibility of such an approach has amply been demonstrated for their plasmidal precursor forms ^[3] ^[4] ^[5] ^[6]

References

^ Nehlsen, K., Broll S., Bode, J. (2006). "Replicating minicircles: Generation of nonviral episomes for the efficient modification of dividing cells". Gene Ther. Mol. Biol. 10: 233–244.
^ Kay, M.A., He, C.-Y, Chen, Z.-H. (2010). "A robust system for production of minicircle DNA vectors". Nature Biotechnology 28: 1287–1289. doi:10.1038/nbt.1708.
^ Broll, S., Oumard A., Hahn K., Schambach A, Bode, J. . (2010). "Minicircle Performance Depending on S/MAR-Nuclear Matrix Interactions". J. Mol. Biol. 395: 950–965. doi:10.1016/j.jmb.2009.11.066.
^ Argyros, O., Wong SP., Fedonidis C.; et al. (2011). "Development of S/MAR minicircles for enhanced and persistent transgene expression in the mouse liver". J. Mol. Med. 89: 515–529. doi:10.1007/s00109-010-0713-3.
^ Heinz, N, Broll S, Schleef M, Baum C, Bode J (2012). "Filling a gap: S/MAR-based replicating minicircles". CliniBook - Nonviral Platform; Clinigene Network: 271–277.
^ Nehlsen, S, Broll S, Kandimalla R, Heinz N, Heine M, Binius S, Schambach A & Bode J (2013). "Replicating Minicircles: Overcoming the limitations of transient and of stable expression systems". Minicircle and Plasmid DNA Vectors - The Future of non-viral and viral Gene-Transfer, Schleef, M. (ed.), ISBN 978-3-527-32456-9 - Wiley-VCH, Weinheim: 115–162.

English Journal

Improved intracellular delivery of peptide- and lipid-nanoplexes by natural glycosides.

Weng A1, Manunta MD2, Thakur M3, Gilabert-Oriol R4, Tagalakis AD2, Eddaoudi A2, Munye MM2, Vink CA2, Wiesner B5, Eichhorst J5, Melzig MF4, Hart SL6.
Journal of controlled release : official journal of the Controlled Release Society.J Control Release.2015 May 28;206:75-90. doi: 10.1016/j.jconrel.2015.03.007. Epub 2015 Mar 7.
Targeted nanocarriers undergo endocytosis upon binding to their membrane receptors and are transported into cellular compartments such as late endosomes and lysosomes. In gene delivery the genetic material has to escape from the cellular compartments into the cytosol. The process of endosomal escape
PMID 25758332

Healing of massive segmental femoral bone defects in minipigs by allogenic ASCs engineered with FLPo/Frt-based baculovirus vectors.

Lin CY1, Wang YH2, Li KC1, Sung LY1, Yeh CL1, Lin KJ3, Yen TC4, Chang YH5, Hu YC6.
Biomaterials.Biomaterials.2015 May;50:98-106. doi: 10.1016/j.biomaterials.2015.01.052. Epub 2015 Feb 16.
Adipose-derived stem cells (ASCs) hold promise for bone regeneration but possess inferior osteogenesis potential. Allotransplantation of ASCs engineered with the BMP2/VEGF-expressing baculoviruses into rabbits healed critical-size segmental bone defects. To translate the technology to clinical appli
PMID 25736500

Preclinical Safety Evaluation of ASCs Engineered by FLPo/Frt-Based Hybrid Baculovirus: In Vitro and Large Animal Studies.

Li KC1, Chang YH, Lin CY, Hwang SM, Wang TH, Hu YC.
Tissue engineering. Part A.Tissue Eng Part A.2015 May;21(9-10):1471-82. doi: 10.1089/ten.TEA.2014.0465. Epub 2015 Mar 6.
We recently developed hybrid baculovirus (BV) vectors that exploited FLPo/Frt-mediated DNA minicircle formation. Engineering of adipose-derived stem cells (ASCs) with the FLPo/Frt-based BV vectors enabled prolonged transgene expression and, after cell implantation into rabbits, ameliorated cartilage
PMID 25602313

Japanese Journal

A New Molecular Surveillance System for Leishmaniasis

The American Journal of Tropical Medicine and Hygiene, 90(6), pp.1082-1086; 2014 90(6), 1082-1086, 2014-06
NAID 120005457074

Subcellular localization of minicircle DNA in the dinoflagellate Amphidinium massartii

Phycological research 62(1), 1-8, 2014-01
NAID 40019980082

Testing the Use of Implicit Solvent in the Molecular Dynamics Modelling of DNA Flexibility(Statistical Physics and Topology of Polymers with Ramifications to Structure and Function of DNA and Proteins)