Matrix attachment regions and regulated transcription increase and stabilize transgene expression

Matrix attachment regions (MARs) are thought to participate in the organization and segregation of independent chromosomal loop domains. Although there are several reports on the action of natural MARs in the context of heterologous genes in transgenic plants, in our study we tested a synthetic MAR (sMAR) with the special property of unpairing when under superhelical strain, for its effect on reporter gene expression in tobacco plants. The synthetic MAR was a multimer of a short sequence from the MAR 3' end of the immunoglobulin heavy chain (IgH) enhancer. This sMAR sequence was used to flank the beta-glucuronidase (GUS) reporter gene within the T-DNA of the binary vector pBI121. Vectors with or without the sMARs were then used to transform tobacco plants by Agrobacterium tumefaciens. Transgenic plants containing the sMAR sequences flanking the GUS gene exhibited higher levels of transgene expression compared with transgenic plants which lacked the sMARs. This effect was observed independently of the position of the sMAR at the 5' side of the reporter gene. However, variation of the detected transgene expression was significant in all transformed plant populations, irrespective of the construct used.

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Heritable transgene expression pattern imposed onto maize ubiquitin promoter by maize adh-1 matrix attachment regions: tissue and developmental specificity in maize transgenic plants

Plant Cell Reports ◽

10.1007/s00299-004-0779-x ◽

2004 ◽

Vol 22 (12) ◽

Cited By ~ 11

Author(s):

Fran�ois Torney ◽

Anne Partier ◽

V�ronique Says-Lesage ◽

Isabelle Nadaud ◽

Pierre Barret ◽

...

Keyword(s):

Transgenic Plants ◽

Expression Pattern ◽

Transgene Expression ◽

Matrix Attachment Regions ◽

Ubiquitin Promoter ◽

Maize Ubiquitin Promoter

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Matrix attachment regions increase transgene expression levels and stability in transgenic rice plants and their progeny

The Plant Journal ◽

10.1046/j.1365-313x.1999.00446.x ◽

1999 ◽

Vol 18 (3) ◽

pp. 233-242 ◽

Cited By ~ 58

Author(s):

Philippe Vain ◽

Barbara Worland ◽

Ajay Kohli ◽

John W. Snape ◽

Paul Christou ◽

...

Keyword(s):

Transgenic Rice ◽

Transgene Expression ◽

Matrix Attachment Regions ◽

Expression Levels ◽

Rice Plants ◽

Transgenic Rice Plants

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1297. Regulated Transgene Expression in B-Lymphocytes from Lentiviral Vectors Carrying the Immunoglobulin Heavy Chain Enhancer with Matrix Attachment Regions

Molecular Therapy ◽

10.1016/s1525-0016(16)44127-4 ◽

2002 ◽

Vol 5 (5) ◽

pp. S424

Keyword(s):

B Lymphocytes ◽

Heavy Chain ◽

Transgene Expression ◽

Lentiviral Vectors ◽

Immunoglobulin Heavy Chain ◽

Matrix Attachment Regions

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Human Matrix Attachment Regions Insulate Transgene Expression from Chromosomal Position Effects in Drosophila melanogaster

Molecular and Cellular Biology ◽

10.1128/mcb.18.4.2382 ◽

1998 ◽

Vol 18 (4) ◽

pp. 2382-2391 ◽

Cited By ~ 69

Author(s):

Stephanie J. Namciu ◽

Karen B. Blochlinger ◽

R. E. K. Fournier

Keyword(s):

Drosophila Melanogaster ◽

Transgene Expression ◽

Germ Line ◽

Binding Activity ◽

Matrix Attachment Regions ◽

Position Effects ◽

Eye Color ◽

Insulator Activity ◽

Insulator Elements

ABSTRACT Germ line transformation of white−Drosophila embryos with P-element vectors containingwhite expression cassettes results in flies with different eye color phenotypes due to position effects at the sites of transgene insertion. These position effects can be cured by specific DNA elements, such as the Drosophila scs and scs′elements, that have insulator activity in vivo. We have used this system to determine whether human matrix attachment regions (MARs) can function as insulator elements in vivo. Two different human MARs, from the apolipoprotein B and α1-antitrypsin loci, insulatedwhite transgene expression from position effects inDrosophila melanogaster. Both elements reduced variability in transgene expression without enhancing levels of whitegene expression. In contrast, expression of whitetransgenes containing human DNA segments without matrix-binding activity was highly variable in Drosophila transformants. These data indicate that human MARs can function as insulator elements in vivo.

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Shortened nuclear matrix attachment regions are sufficient for replication and maintenance of episomes in mammalian cells

Molecular Biology of the Cell ◽

10.1091/mbc.e19-02-0108 ◽

2019 ◽

Vol 30 (22) ◽

pp. 2761-2770

Author(s):

Xiao-Yin Wang ◽

Xi Zhang ◽

Tian-Yun Wang ◽

Yan-Long Jia ◽

Dan-Hua Xu ◽

...

Keyword(s):

Nuclear Matrix ◽

Cho Cells ◽

Mammalian Cells ◽

Transgene Expression ◽

Matrix Attachment Regions ◽

Expression Levels ◽

Episomal Vector ◽

Maintenance Mechanism ◽

Molecular Mode ◽

Episomal Maintenance

Matrix attachment regions (MARs) can mediate the replication of vector episomes in mammalian cells; however, the molecular mode of action remains unclear. Here, we assessed the characteristics of MARs and the mechanism that mediates episomal vector replication in mammalian cells. Five shortened subfragments of β-interferon MAR fragments were cloned and transferred into CHO cells, and transgene expression levels, presence of the gene, and the episomal maintenance mechanism were determined. Three shortened MAR derivatives (position 781–1320, 1201–1740, and 1621–2201) retained full MAR activity and mediated episomal vector replication. Moreover, the three shortened MARs showed higher transgene expression levels, greater efficiency in colony formation, and more persistent transgene expression compared with those of the original pEPI-1 plasmid, and three functional truncated MARs can bind to SAF-A MAR-binding protein. These results suggest that shortened MARs are sufficient for replication and maintenance of episomes in CHO cells.

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