ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Publication Date: 2014-11-15
    Description: DNA double-strand breaks (DSBs) are introduced in meiosis to initiate recombination and generate crossovers, the reciprocal exchanges of genetic material between parental chromosomes. Here, we present high-resolution maps of meiotic DSBs in individual human genomes. Comparing DSB maps between individuals shows that along with DNA binding by PRDM9, additional factors may dictate the efficiency of DSB formation. We find evidence for both GC-biased gene conversion and mutagenesis around meiotic DSB hotspots, while frequent colocalization of DSB hotspots with chromosome rearrangement breakpoints implicates the aberrant repair of meiotic DSBs in genomic disorders. Furthermore, our data indicate that DSB frequency is a major determinant of crossover rate. These maps provide new insights into the regulation of meiotic recombination and the impact of meiotic recombination on genome function.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Pratto, Florencia -- Brick, Kevin -- Khil, Pavel -- Smagulova, Fatima -- Petukhova, Galina V -- Camerini-Otero, R Daniel -- 1R01GM084104-01A1/GM/NIGMS NIH HHS/ -- Intramural NIH HHS/ -- New York, N.Y. -- Science. 2014 Nov 14;346(6211):1256442. doi: 10.1126/science.1256442.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉National Institute of Diabetes, Digestive and Kidney Diseases, NIH, Bethesda, MD, USA. ; Department of Biochemistry and Molecular Biology, Uniformed Services University of Health Sciences, Bethesda, MD, USA. ; Department of Biochemistry and Molecular Biology, Uniformed Services University of Health Sciences, Bethesda, MD, USA. rdcamerini@mail.nih.gov galina.petukhova@usuhs.edu. ; National Institute of Diabetes, Digestive and Kidney Diseases, NIH, Bethesda, MD, USA. rdcamerini@mail.nih.gov galina.petukhova@usuhs.edu.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25395542" target="_blank"〉PubMed〈/a〉
    Keywords: Alleles ; *Chromosome Mapping ; *DNA Breaks, Double-Stranded ; Genome, Human/*genetics ; *Genomic Instability ; Histone-Lysine N-Methyltransferase/genetics/metabolism ; *Homologous Recombination ; Humans ; Male ; Meiosis/*genetics ; Protein Binding ; Spermatocytes ; Telomere/genetics
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Publication Date: 2012-06-23
    Description: In female (XX) mammals, one of the two X chromosomes is inactivated to ensure an equal dose of X-linked genes with males (XY). X-chromosome inactivation in eutherian mammals is mediated by the non-coding RNA Xist. Xist is not found in metatherians (marsupials), and how X-chromosome inactivation is initiated in these mammals has been the subject of speculation for decades. Using the marsupial Monodelphis domestica, here we identify Rsx (RNA-on-the-silent X), an RNA that has properties consistent with a role in X-chromosome inactivation. Rsx is a large, repeat-rich RNA that is expressed only in females and is transcribed from, and coats, the inactive X chromosome. In female germ cells, in which both X chromosomes are active, Rsx is silenced, linking Rsx expression to X-chromosome inactivation and reactivation. Integration of an Rsx transgene on an autosome in mouse embryonic stem cells leads to gene silencing in cis. Our findings permit comparative studies of X-chromosome inactivation in mammals and pose questions about the mechanisms by which X-chromosome inactivation is achieved in eutherians.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3484893/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3484893/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Grant, Jennifer -- Mahadevaiah, Shantha K -- Khil, Pavel -- Sangrithi, Mahesh N -- Royo, Helene -- Duckworth, Janine -- McCarrey, John R -- VandeBerg, John L -- Renfree, Marilyn B -- Taylor, Willie -- Elgar, Greg -- Camerini-Otero, R Daniel -- Gilchrist, Mike J -- Turner, James M A -- HD60858/HD/NICHD NIH HHS/ -- MC_U117597137/Medical Research Council/United Kingdom -- MC_U117597141/Medical Research Council/United Kingdom -- U117581331/Medical Research Council/United Kingdom -- U117588498/Medical Research Council/United Kingdom -- U117597137/Medical Research Council/United Kingdom -- U117597141/Medical Research Council/United Kingdom -- Z99 DK999999/Intramural NIH HHS/ -- ZIA DK052035-05/Intramural NIH HHS/ -- England -- Nature. 2012 Jul 12;487(7406):254-8. doi: 10.1038/nature11171.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉MRC National Institute for Medical Research, The Ridgeway, Mill Hill, London NW71AA, UK.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/22722828" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Female ; Gene Expression Regulation ; Gene Silencing ; Mice ; Monodelphis/*genetics/*metabolism ; RNA/*genetics/*metabolism ; Transgenes ; X Chromosome/*genetics/*metabolism ; *X Chromosome Inactivation
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Publication Date: 2012-06-05
    Description: Genetic recombination occurs during meiosis, the key developmental programme of gametogenesis. Recombination in mammals has been recently linked to the activity of a histone H3 methyltransferase, PR domain containing 9 (PRDM9), the product of the only known speciation-associated gene in mammals. PRDM9 is thought to determine the preferred recombination sites--recombination hotspots--through sequence-specific binding of its highly polymorphic multi-Zn-finger domain. Nevertheless, Prdm9 knockout mice are proficient at initiating recombination. Here we map and analyse the genome-wide distribution of recombination initiation sites in Prdm9 knockout mice and in two mouse strains with different Prdm9 alleles and their F(1) hybrid. We show that PRDM9 determines the positions of practically all hotspots in the mouse genome, with the exception of the pseudo-autosomal region (PAR)--the only area of the genome that undergoes recombination in 100% of cells. Surprisingly, hotspots are still observed in Prdm9 knockout mice, and as in wild type, these hotspots are found at H3 lysine 4 (H3K4) trimethylation marks. However, in the absence of PRDM9, most recombination is initiated at promoters and at other sites of PRDM9-independent H3K4 trimethylation. Such sites are rarely targeted in wild-type mice, indicating an unexpected role of the PRDM9 protein in sequestering the recombination machinery away from gene-promoter regions and other functional genomic elements.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3367396/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3367396/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Brick, Kevin -- Smagulova, Fatima -- Khil, Pavel -- Camerini-Otero, R Daniel -- Petukhova, Galina V -- 1R01GM084104-01A1/GM/NIGMS NIH HHS/ -- R01 GM084104/GM/NIGMS NIH HHS/ -- R01 GM084104-01A1/GM/NIGMS NIH HHS/ -- Intramural NIH HHS/ -- England -- Nature. 2012 May 13;485(7400):642-5. doi: 10.1038/nature11089.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉National Institute of Diabetes, Digestive and Kidney Diseases, NIH, Bethesda, Maryland 20892, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/22660327" target="_blank"〉PubMed〈/a〉
    Keywords: Alleles ; Amino Acid Sequence ; Animals ; Base Sequence ; *DNA Breaks, Double-Stranded ; Genome/*genetics ; Histone-Lysine N-Methyltransferase/deficiency/genetics/*metabolism ; Histones/chemistry/metabolism ; Meiosis/genetics ; Methylation ; Mice ; Mice, Knockout ; Molecular Sequence Data ; Promoter Regions, Genetic/*genetics ; Recombination, Genetic/*genetics
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Publication Date: 2011-04-05
    Description: Meiotic recombination predominantly occurs at discrete genomic loci called recombination hotspots, but the features defining these areas are still largely unknown (reviewed in refs 1-5). To allow a comprehensive analysis of hotspot-associated DNA and chromatin characteristics, we developed a direct molecular approach for mapping meiotic DNA double-strand breaks that initiate recombination. Here we present the genome-wide distribution of recombination initiation sites in the mouse genome. Hotspot centres are mapped with approximately 200-nucleotide precision, which allows analysis of the fine structural details of the preferred recombination sites. We determine that hotspots share a centrally distributed consensus motif, possess a nucleotide skew that changes polarity at the centres of hotspots and have an intrinsic preference to be occupied by a nucleosome. Furthermore, we find that the vast majority of recombination initiation sites in mouse males are associated with testis-specific trimethylation of lysine 4 on histone H3 that is distinct from histone H3 lysine 4 trimethylation marks associated with transcription. The recombination map presented here has been derived from a homogeneous mouse population with a defined genetic background and therefore lends itself to extensive future experimental exploration. We note that the mapping technique developed here does not depend on the availability of genetic markers and hence can be easily adapted to other species with complex genomes. Our findings uncover several fundamental features of mammalian recombination hotspots and underline the power of the new recombination map for future studies of genetic recombination, genome stability and evolution.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3117304/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3117304/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Smagulova, Fatima -- Gregoretti, Ivan V -- Brick, Kevin -- Khil, Pavel -- Camerini-Otero, R Daniel -- Petukhova, Galina V -- 1R01GM084104-01A1/GM/NIGMS NIH HHS/ -- R01 GM084104/GM/NIGMS NIH HHS/ -- R01 GM084104-01A1/GM/NIGMS NIH HHS/ -- Intramural NIH HHS/ -- England -- Nature. 2011 Apr 21;472(7343):375-8. doi: 10.1038/nature09869. Epub 2011 Apr 3.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Uniformed Services University of the Health Sciences, Bethesda, Maryland 20814, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/21460839" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Chromosome Mapping/*methods ; Chromosome Segregation ; Chromosomes, Mammalian/*genetics ; Consensus Sequence ; Crossing Over, Genetic/genetics ; *DNA Breaks, Double-Stranded ; Genetic Markers ; Genome/*genetics ; Genomics ; Histones/metabolism ; Lysine/metabolism ; Male ; Meiosis/*genetics ; Methylation ; Mice ; Mice, Inbred C57BL ; Molecular Sequence Data ; Nucleosomes/genetics/metabolism ; Organ Specificity ; Recombination, Genetic/*genetics ; Sister Chromatid Exchange/genetics ; Testis/metabolism ; Transcription, Genetic/genetics
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Publication Date: 2012-01-30
    Print ISSN: 0027-8424
    Electronic ISSN: 1091-6490
    Topics: Biology , Medicine , Natural Sciences in General
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Publication Date: 2012-02-15
    Description: The protein Vezf1 plays multiple roles important for embryonic development. In Vezf1−/− mouse embryonic stem (mES) cells, our earlier data showed widespread changes in gene-expression profiles, including decreased expression of the full-length active isoform of Dnmt3b methyltransferase and concomitant genome-wide reduction in DNA methylation. Here we show that in HeLaS3 cells there is a strong genome-wide correlation between Vezf1 binding and peaks of elongating Ser2-P RNA polymerase (Pol) ll, reflecting Vezf1-dependent slowing of elongation. In WT mES cells, the elongating form of RNA pol II accumulates near Vezf1 binding sites within the dnmt3b gene and at several other Vezf1 sites, and this accumulation is significantly reduced at these sites in Vezf1−/− mES cells. Depending upon genomic location, Vezf1-mediated Pol II pausing can have different regulatory roles in transcription and splicing. We find examples of genes in which Vezf1 binding sites are located near cassette exons, and in which loss of Vezf1 leads to a change in the relative abundance of alternatively spliced messages. We further show that Vezf1 interacts with Mrg15/Mrgbp, a protein that recognizes H3K36 trimethylation, consistent with the role of histone modifications at alternatively spliced sites.
    Print ISSN: 0027-8424
    Electronic ISSN: 1091-6490
    Topics: Biology , Medicine , Natural Sciences in General
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Publication Date: 2014-01-28
    Description: The Hop2–Mnd1 complex functions with the DMC1 recombinase in meiotic recombination. Hop2–Mnd1 stabilizes the DMC1-single-stranded DNA (ssDNA) filament and promotes the capture of the double-stranded DNA partner by the recombinase filament to assemble the synaptic complex. Herein, we define the action mechanism of Hop2–Mnd1 in DMC1-mediated recombination. Small angle X-ray scattering analysis and electron microscopy reveal that the heterodimeric Hop2–Mnd1 is a V-shaped molecule. We show that the protein complex harbors three distinct DNA binding sites, and determine their functional relevance. Specifically, the N-terminal double-stranded DNA binding functions of Hop2 and Mnd1 co-operate to mediate synaptic complex assembly, whereas ssDNA binding by the Hop2 C-terminus helps stabilize the DMC1-ssDNA filament. A model of the Hop2-Mnd1-DMC1-ssDNA ensemble is proposed to explain how it mediates homologous DNA pairing in meiotic recombination.
    Print ISSN: 0305-1048
    Electronic ISSN: 1362-4962
    Topics: Biology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Publication Date: 2014-02-28
    Description: Deletion of Hop2 in mice eliminates homologous chromosome synapsis and disrupts double-strand break (DSB) repair through homologous recombination. HOP2 in vitro shows two distinctive activities: when it is incorporated into a HOP2–MND1 complex it stimulates DMC1 and RAD51 recombination activities and the purified HOP2 alone is proficient in promoting strand invasion. We observed that a fraction of Mnd1 –/– spermatocytes, which express HOP2 but apparently have inactive DMC1 and RAD51 due to lack of the HOP2–MND1 complex, exhibits a high level of chromosome synapsis and that most DSBs in these spermatocytes are repaired. This suggests that DSB repair catalyzed solely by HOP2 supports homologous chromosome pairing and synapsis. In addition, we show that in vitro HOP2 promotes the co-aggregation of ssDNA with duplex DNA, binds to ssDNA leading to unstacking of the bases, and promotes the formation of a three-strand synaptic intermediate. However, HOP2 shows distinctive mechanistic signatures as a recombinase. Namely, HOP2-mediated strand exchange does not require ATP and, in contrast to DMC1, joint molecules formed by HOP2 are more sensitive to mismatches and are efficiently dissociated by RAD54. We propose that HOP2 may act as a recombinase with specific functions in meiosis.
    Print ISSN: 0305-1048
    Electronic ISSN: 1362-4962
    Topics: Biology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...