Abstract:
:Dyskerin binds the H/ACA box of human telomerase RNA and is a core telomerase subunit required for RNP biogenesis and enzyme function in vivo. Missense mutations in dyskerin result in dyskeratosis congenita, a complex syndrome characterized by bone marrow failure, telomerase enzyme deficiency, and progressive telomere shortening. Here we demonstrate that dyskerin also contributes to telomere maintenance in Arabidopsis thaliana. We report that both AtNAP57, the Arabidopsis dyskerin homolog, and AtTERT, the telomerase catalytic subunit, accumulate in the plant nucleolus, and AtNAP57 associates with active telomerase RNP particles in an RNA-dependent manner. Furthermore, AtNAP57 interacts in vitro with AtPOT1a, a novel component of Arabidopsis telomerase. Although a null mutation in AtNAP57 is lethal, AtNAP57, like AtTERT, is not haploinsufficient for telomere maintenance in Arabidopsis. However, introduction of an AtNAP57 allele containing a T66A mutation decreased telomerase activity in vitro, disrupted telomere length regulation on individual chromosome ends in vivo, and established a new, shorter telomere length set point. These results imply that T66A NAP57 behaves as a dominant-negative inhibitor of telomerase. We conclude that dyskerin is a conserved component of the telomerase RNP complex in higher eukaryotes that is required for maximal enzyme activity in vivo.
journal_name
Mol Cell Bioljournal_title
Molecular and cellular biologyauthors
Kannan K,Nelson AD,Shippen DEdoi
10.1128/MCB.01490-07subject
Has Abstractpub_date
2008-04-01 00:00:00pages
2332-41issue
7eissn
0270-7306issn
1098-5549pii
MCB.01490-07journal_volume
28pub_type
杂志文章abstract::We have previously shown that Saccharomyces cerevisiae Isw2 complex slides nucleosomes to remodel chromatin in vivo. Our data suggested a model in which Isw2 complex binds the histone octamer and DNA separately to generate the force necessary for nucleosome movement. Here we find that the histone H4 "basic patch" is t...
journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/MCB.25.21.9165-9174.2005
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journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.19.3.1928
更新日期:1999-03-01 00:00:00
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journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.13.8.4918
更新日期:1993-08-01 00:00:00
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journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.19.6.4200
更新日期:1999-06-01 00:00:00
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journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.20.14.5248-5255.2000
更新日期:2000-07-01 00:00:00
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journal_title:Molecular and cellular biology
pub_type: 杂志文章
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pub_type: 杂志文章
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pub_type: 杂志文章
doi:10.1128/mcb.9.2.639
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journal_title:Molecular and cellular biology
pub_type: 杂志文章
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更新日期:1989-01-01 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:2003-07-01 00:00:00
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journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.17.1.100
更新日期:1997-01-01 00:00:00
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journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/MCB.21.15.5041-5049.2001
更新日期:2001-08-01 00:00:00
abstract::The yeast Mcm1 protein is a member of the MADS box family of transcriptional regulatory factors, a class of DNA-binding proteins that control numerous cellular and developmental processes in yeast, Drosophila melanogaster, plants, and mammals. Although these proteins bind DNA on their own, they often combine with diff...
journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.22.13.4607-4621.2002
更新日期:2002-07-01 00:00:00
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journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.18.3.1534
更新日期:1998-03-01 00:00:00
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journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.14.11.7256
更新日期:1994-11-01 00:00:00
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journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.17.7.3547
更新日期:1997-07-01 00:00:00
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journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/MCB.25.11.4335-4348.2005
更新日期:2005-06-01 00:00:00
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journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.17.6.3315
更新日期:1997-06-01 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:2006-08-01 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:1990-04-01 00:00:00
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journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.7.1.528
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
doi:10.1128/mcb.13.3.1863
更新日期:1993-03-01 00:00:00
abstract::The Drosophila Hrb98DE locus encodes proteins that are highly homologous to the mammalian A1 protein, a major component of heterogeneous nuclear ribonucleoprotein (RNP) particles. The Hrb98DE locus is transcribed throughout development, with the highest transcript levels found in ovaries, early embryos, and pupae. Eig...
journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.10.1.316
更新日期:1990-01-01 00:00:00
abstract::We have identified stable transcripts from the so-called nontranscribed spacer region (NTS) of the nuclear ribosomal DNA repeat in certain respiration-deficient strains of Saccharomyces cerevisiae. These RNAs, which are transcribed from the same strand as is the 37S rRNA precursor, are 500 to 800 nucleotides long and ...
journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.9.5.1897
更新日期:1989-05-01 00:00:00
abstract::Phospholipase C-gamma2 (PLC-gamma2) plays an important role in B-cell signaling. Phosphorylation of various tyrosine residues of PLC-gamma2 has been implicated in regulation of its lipase activity. With the use of antibodies specific for each of the putative phosphorylation sites, we have now shown that PLC-gamma2 is ...
journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/MCB.24.22.9986-9999.2004
更新日期:2004-11-01 00:00:00
abstract::Barsoum and Varshavsky (Proc. Natl. Acad. Sci. U.S.A. 80:5330-5334, 1983) suggest that polypeptide mitogens and the mitogenic tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA) stimulate gene amplification by related pathways. I demonstrated that TPA and the polypeptide mitogen fibroblast growth factor (FGF) bo...
journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.5.5.1130
更新日期:1985-05-01 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:2008-01-01 00:00:00
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journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.12.2.552
更新日期:1992-02-01 00:00:00
abstract::Nuclear extracts from chicken erythroid cells selectively stimulate transcription of the chicken histone H5 gene (and not of other chicken histone genes) after coinjection into frog oocytes. This effect is shown to involve an enhancerlike activity, and a region of the H5 gene sufficient to mediate trans-activation is ...
journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.7.10.3853
更新日期:1987-10-01 00:00:00
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journal_title:Molecular and cellular biology
pub_type: 杂志文章
doi:10.1128/mcb.11.5.2375
更新日期:1991-05-01 00:00:00