Abstract:
:Intracisternal A-particle (IAP) sequences are endogenous retrovirus-like mobile elements, or retrotransposons, present at 1,000 copies in the mouse genome. These elements transpose in a replicative manner via an RNA intermediate and its reverse transcription, and their transposition should therefore be tightly controlled by their transcription level. To analyze the in vivo pattern of expression of these retrovirus-like elements, we constructed several independent transgenic mice with either a complete IAP element marked with an intron or with the IAP promoter, or long terminal repeat (LTR), alone controlling the expression of a lacZ reporter gene with a nuclear localization signal. For all transgenic lines analyzed, IAP expression as determined by reverse transcription-PCR analysis was found to be essentially restricted to the male germ line. Furthermore, in situ 5-bromo-4-chloro-3-indolyl-beta-D-galactopyranoside (X-Gal) staining of all organs disclosed specific beta-galactosidase-positive blue cells only within the testis, found as patches along the seminiferous tubules and often organized as assemblies of 2, 4, 8, or 16 cells. Histochemical analyses of tissues from 13.5-day-old embryos to adults demonstrated that this LTR activity is restricted to gonocytes and premeiotic undifferentiated spermatogonia. Finally, analysis of the methylation status of both transgenes and endogenous IAP LTRs demonstrated identical patterns, with methylation in somatic tissues and hypomethylation in the testis. Transgenic mice therefore reveal an intrinsic, highly restricted IAP expression which had escaped detection in previous global Northern (RNA) blot analyses and with possible strong biological relevance, as IAP activation specifically within the germ line might be a way to generate diversity at the evolutionary level without being deleterious to individuals.
journal_name
Mol Cell Bioljournal_title
Molecular and cellular biologyauthors
Dupressoir A,Heidmann Tdoi
10.1128/mcb.16.8.4495subject
Has Abstractpub_date
1996-08-01 00:00:00pages
4495-503issue
8eissn
0270-7306issn
1098-5549journal_volume
16pub_type
杂志文章abstract::Repetitive DNA sequences have been implicated in the mediation of DNA rearrangement in mammalian cells. We have tested this hypothesis by using a dihydrofolate reductase (DHFR) expression vector into which candidate sequences were inserted. DHFR- Chinese hamster ovary (CHO) cells were transfected with this vector, the...
journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.8.9.3611
更新日期:1988-09-01 00:00:00
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journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.11.4.2040
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journal_title:Molecular and cellular biology
pub_type: 杂志文章
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journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.7.1.403
更新日期:1987-01-01 00:00:00
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journal_title:Molecular and cellular biology
pub_type: 杂志文章
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更新日期:1999-10-01 00:00:00
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pub_type: 杂志文章
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更新日期:1990-08-01 00:00:00
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pub_type: 杂志文章
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更新日期:1998-02-01 00:00:00
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journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.4.5.840
更新日期:1984-05-01 00:00:00
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journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/MCB.00499-18
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journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.7.8.2933
更新日期:1987-08-01 00:00:00
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journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/MCB.00603-07
更新日期:2007-08-01 00:00:00
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journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.17.12.7398
更新日期:1997-12-01 00:00:00
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journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/MCB.26.4.1510-1517.2006
更新日期:2006-02-01 00:00:00
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journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.15.10.5312
更新日期:1995-10-01 00:00:00
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pub_type: 杂志文章
doi:10.1128/mcb.14.4.2777
更新日期:1994-04-01 00:00:00
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journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.4.7.1293
更新日期:1984-07-01 00:00:00
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journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/MCB.00296-13
更新日期:2013-08-01 00:00:00
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journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.7.4.1450
更新日期:1987-04-01 00:00:00
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journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.10.6.2765
更新日期:1990-06-01 00:00:00
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journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.7.5.1917
更新日期:1987-05-01 00:00:00
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journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.14.6.3876
更新日期:1994-06-01 00:00:00
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journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.18.4.2077
更新日期:1998-04-01 00:00:00
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journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/MCB.21.10.3445-3450.2001
更新日期:2001-05-01 00:00:00
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journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.16.6.2987
更新日期:1996-06-01 00:00:00
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journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.19.12.8146
更新日期:1999-12-01 00:00:00
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journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/MCB.01674-07
更新日期:2008-05-01 00:00:00
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journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/MCB.21.14.4748-4760.2001
更新日期:2001-07-01 00:00:00
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journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.11.7.3682
更新日期:1991-07-01 00:00:00
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journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/MCB.01510-09
更新日期:2010-05-01 00:00:00
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journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.23.3.1061-1074.2003
更新日期:2003-02-01 00:00:00