Nucleus (Austin, Tex.)最新文献_第7页

Are the processes of DNA replication and DNA repair reading a common structural chromatin unit? DNA复制和DNA修复是一个共同的染色质结构单元吗?

Nucleus (Austin, Tex.) Pub Date : 2020-12-01 DOI: 10.1080/19491034.2020.1744415

Stefania Mamberti, M Cristina Cardoso

{"title":"Are the processes of DNA replication and DNA repair reading a common structural chromatin unit?","authors":"Stefania Mamberti, M Cristina Cardoso","doi":"10.1080/19491034.2020.1744415","DOIUrl":"https://doi.org/10.1080/19491034.2020.1744415","url":null,"abstract":"Decades of investigation on genomic DNA have brought us deeper insights into its organization within the nucleus and its metabolic mechanisms. This was fueled by the parallel development of experimental techniques and has stimulated model building to simulate genome conformation in agreement with the experimental data. Here, we will discuss our recent discoveries on the chromatin units of DNA replication and DNA damage response. We will highlight their remarkable structural similarities and how both revealed themselves as clusters of nanofocal structures each on the hundred thousand base pair size range corresponding well with chromatin loop sizes. We propose that the function of these two global genomic processes is determined by the loop level organization of chromatin structure with structure dictating function.Abbreviations: 3D-SIM: 3D-structured illumination microscopy; 3C: chromosome conformation capture; DDR: DNA damage response; FISH: fluorescent in situ hybridization; Hi-C: high conformation capture; HiP-HoP: highly predictive heteromorphic polymer model; IOD: inter-origin distance; LAD: lamina associated domain; STED: stimulated emission depletion microscopy; STORM: stochastic optical reconstruction microscopy; SBS: strings and binders switch model; TAD: topologically associated domain.","PeriodicalId":74323,"journal":{"name":"Nucleus (Austin, Tex.)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/19491034.2020.1744415","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"37821767","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 6

LINC-complex mediated positioning of the vegetative nucleus is involved in calcium and ROS signaling in Arabidopsis pollen tubes. 拟南芥花粉管中linc复合物介导的营养核定位参与钙和ROS信号传导。

Nucleus (Austin, Tex.) Pub Date : 2020-12-01 DOI: 10.1080/19491034.2020.1783783

Morgan Moser, Andrew Kirkpatrick, Norman Reid Groves, Iris Meier

{"title":"LINC-complex mediated positioning of the vegetative nucleus is involved in calcium and ROS signaling in Arabidopsis pollen tubes.","authors":"Morgan Moser, Andrew Kirkpatrick, Norman Reid Groves, Iris Meier","doi":"10.1080/19491034.2020.1783783","DOIUrl":"https://doi.org/10.1080/19491034.2020.1783783","url":null,"abstract":"Nuclear movement and positioning play a role in developmental processes throughout life. Nuclear movement and positioning are mediated primarily by linker of nucleoskeleton and cytoskeleton (LINC) complexes. LINC complexes are comprised of the inner nuclear membrane SUN proteins and the outer nuclear membrane (ONM) KASH proteins. In Arabidopsis pollen tubes, the vegetative nucleus (VN) maintains a fixed distance from the pollen tube tip during growth, and the VN precedes the sperm cells (SCs). In pollen tubes of wit12 and wifi, mutants deficient in the ONM component of a plant LINC complex, the SCs precede the VN during pollen tube growth and the fixed VN distance from the tip is lost. Subsequently, pollen tubes frequently fail to burst upon reception. In this study, we sought to determine if the pollen tube reception defect observed in wit12 and wifi is due to decreased sensitivity to reactive oxygen species (ROS). Here, we show that wit12 and wifi are hyposensitive to exogenous H2O2, and that this hyposensitivity is correlated with decreased proximity of the VN to the pollen tube tip. Additionally, we report the first instance of nuclear Ca2+ peaks in growing pollen tubes, which are disrupted in the wit12 mutant. In the wit12 mutant, nuclear Ca2+ peaks are reduced in response to exogenous ROS, but these peaks are not correlated with pollen tube burst. This study finds that VN proximity to the pollen tube tip is required for both response to exogenous ROS, as well as internal nuclear Ca2+ fluctuations.","PeriodicalId":74323,"journal":{"name":"Nucleus (Austin, Tex.)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/19491034.2020.1783783","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38125161","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 11

CTCF as a boundary factor for cohesin-mediated loop extrusion: evidence for a multi-step mechanism. CTCF 作为凝聚素介导的环挤压的边界因子：多步骤机制的证据。

Nucleus (Austin, Tex.) Pub Date : 2020-12-01 DOI: 10.1080/19491034.2020.1782024

Anders S Hansen

引用次数: 45

Lamin microaggregates lead to altered mechanotransmission in progerin-expressing cells. 纤层蛋白微聚集体导致表达早衰蛋白的细胞机械传递的改变。

Nucleus (Austin, Tex.) Pub Date : 2020-12-01 DOI: 10.1080/19491034.2020.1802906

Brooke E Danielsson, Katie V Tieu, Kranthidhar Bathula, Travis J Armiger, Pragna S Vellala, Rebecca E Taylor, Kris Noel Dahl, Daniel E Conway

{"title":"Lamin microaggregates lead to altered mechanotransmission in progerin-expressing cells.","authors":"Brooke E Danielsson, Katie V Tieu, Kranthidhar Bathula, Travis J Armiger, Pragna S Vellala, Rebecca E Taylor, Kris Noel Dahl, Daniel E Conway","doi":"10.1080/19491034.2020.1802906","DOIUrl":"https://doi.org/10.1080/19491034.2020.1802906","url":null,"abstract":"The nuclear lamina is a meshwork of intermediate filament proteins, and lamin A is the primary mechanical protein. An altered splicing of lamin A, known as progerin, causes the disease Hutchinson-Gilford progeria syndrome. Progerin-expressing cells have altered nuclear shapes and stiffened nuclear lamina with microaggregates of progerin. Here, progerin microaggregate inclusions in the lamina are shown to lead to cellular and multicellular dysfunction. We show with Comsol simulations that stiffened inclusions causes redistribution of normally homogeneous forces, and this redistribution is dependent on the stiffness difference and relatively independent of inclusion size. We also show mechanotransmission changes associated with progerin expression in cells under confinement and cells under external forces. Endothelial cells expressing progerin do not align properly with patterning. Fibroblasts expressing progerin do not align properly to applied cyclic force. Combined, these studies show that altered nuclear lamina mechanics and microstructure impacts cytoskeletal force transmission through the cell.","PeriodicalId":74323,"journal":{"name":"Nucleus (Austin, Tex.)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/19491034.2020.1802906","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38290727","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Mechanical properties of nucleoprotein complexes determined by nanoindentation spectroscopy. 用纳米压痕光谱测定核蛋白复合物的力学性能。

Nucleus (Austin, Tex.) Pub Date : 2020-12-01 DOI: 10.1080/19491034.2020.1816053

Tatini Rakshit, Daniël P Melters, Emilios K Dimitriadis, Yamini Dalal

{"title":"Mechanical properties of nucleoprotein complexes determined by nanoindentation spectroscopy.","authors":"Tatini Rakshit, Daniël P Melters, Emilios K Dimitriadis, Yamini Dalal","doi":"10.1080/19491034.2020.1816053","DOIUrl":"https://doi.org/10.1080/19491034.2020.1816053","url":null,"abstract":"The interplay between transcription factors, chromatin remodelers, 3-D organization, and mechanical properties of the chromatin fiber controls genome function in eukaryotes. Besides the canonical histones which fold the bulk of the chromatin into nucleosomes, histone variants create distinctive chromatin domains that are thought to regulate transcription, replication, DNA damage repair, and faithful chromosome segregation. Whether histone variants translate distinctive biochemical or biophysical properties to their associated chromatin structures, and whether these properties impact chromatin dynamics as the genome undergoes a multitude of transactions, is an important question in biology. Here, we describe single-molecule nanoindentation tools that we developed specifically to determine the mechanical properties of histone variant nucleosomes and their complexes. These methods join an array of cutting-edge new methods that further our quantitative understanding of the response of chromatin to intrinsic and extrinsic forces which act upon it during biological transactions in the nucleus.","PeriodicalId":74323,"journal":{"name":"Nucleus (Austin, Tex.)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/19491034.2020.1816053","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38401300","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Bromodomain AAA+ ATPases get into shape. 溴域AAA+ atp酶形成形状。

Nucleus (Austin, Tex.) Pub Date : 2020-12-01 DOI: 10.1080/19491034.2020.1741304

Magdalena Murawska, Andreas G Ladurner

引用次数: 2

The ESCRT-III complex is required for nuclear pore complex sequestration and regulates gamete replicative lifespan in budding yeast meiosis. 在出芽酵母减数分裂中，ESCRT-III复合体是核孔复合体隔离和调节配子复制寿命所必需的。

Nucleus (Austin, Tex.) Pub Date : 2020-12-01 DOI: 10.1080/19491034.2020.1812872

Bailey A Koch, Elizabeth Staley, Hui Jin, Hong-Guo Yu

{"title":"The ESCRT-III complex is required for nuclear pore complex sequestration and regulates gamete replicative lifespan in budding yeast meiosis.","authors":"Bailey A Koch, Elizabeth Staley, Hui Jin, Hong-Guo Yu","doi":"10.1080/19491034.2020.1812872","DOIUrl":"https://doi.org/10.1080/19491034.2020.1812872","url":null,"abstract":"Cellular aging occurs as a cell loses its ability to maintain homeostasis. Aging cells eliminate damaged cellular compartments and other senescence factors via self-renewal. The mechanism that regulates cellular rejuvenation remains to be further elucidated. Using budding yeast gametogenesis as a model, we show here that the endosomal sorting complex required for transport (ESCRT) III regulates nuclear envelope organization. During gametogenesis, the nuclear pore complex (NPC) and other senescence factors are sequestered away from the prospore nuclei. We show that the LEM-domain protein Heh1 (Src1) facilitates the nuclear recruitment of ESCRT-III, which is required for meiotic NPC sequestration and nuclear envelope remodeling. Furthermore, ESCRT-III-mediated nuclear reorganization appears to be critical for gamete rejuvenation, as hindering this process curtails either directly or indirectly the replicative lifespan in gametes. Our findings demonstrate the importance of ESCRT-III in nuclear envelope remodeling and its potential role in eliminating senescence factors during gametogenesis.","PeriodicalId":74323,"journal":{"name":"Nucleus (Austin, Tex.)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/19491034.2020.1812872","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38349560","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 8

Impairment of nuclear F-actin formation and its relevance to cellular phenotypes in Hutchinson-Gilford progeria syndrome. 哈钦森-吉尔福德早衰综合征中核f -肌动蛋白形成损伤及其与细胞表型的相关性

Nucleus (Austin, Tex.) Pub Date : 2020-12-01 DOI: 10.1080/19491034.2020.1815395

Yuto Takahashi, Shogo Hiratsuka, Nanako Machida, Daisuke Takahashi, Junpei Matsushita, Pavel Hozak, Tom Misteli, Kei Miyamoto, Masahiko Harata

{"title":"Impairment of nuclear F-actin formation and its relevance to cellular phenotypes in Hutchinson-Gilford progeria syndrome.","authors":"Yuto Takahashi, Shogo Hiratsuka, Nanako Machida, Daisuke Takahashi, Junpei Matsushita, Pavel Hozak, Tom Misteli, Kei Miyamoto, Masahiko Harata","doi":"10.1080/19491034.2020.1815395","DOIUrl":"https://doi.org/10.1080/19491034.2020.1815395","url":null,"abstract":"Hutchinson-Gilford progeria syndrome (HGPS) is a premature aging disorder caused by a mutation of lamin A, which contributes to nuclear architecture and the spatial organization of chromatin in the nucleus. The expression of a lamin A mutant, named progerin, leads to functional and structural disruption of nuclear organization. Since progerin lacks a part of the actin-binding site of lamin A, we hypothesized that nuclear actin dynamics and function are altered in HGPS cells. Nuclear F-actin is required for the organization of nuclear shape, transcriptional regulation, DNA damage repair, and activation of Wnt/β-catenin signaling. Here we show that the expression of progerin decreases nuclear F-actin and impairs F-actin-regulated transcription. When nuclear F-actin levels are increased by overexpression of nuclear-targeted actin or by using jasplakinolide, a compound that stabilizes F-actin, the irregularity of nuclear shape and defects in gene expression can be reversed. These observations provide evidence for a novel relationship between nuclear actin and the etiology of HGPS.","PeriodicalId":74323,"journal":{"name":"Nucleus (Austin, Tex.)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/19491034.2020.1815395","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38403690","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 9

Nuclear lamin phosphorylation: an emerging role in gene regulation and pathogenesis of laminopathies. 核纤层蛋白磷酸化:在纤层病的基因调控和发病机制中的新作用。

Nucleus (Austin, Tex.) Pub Date : 2020-12-01 DOI: 10.1080/19491034.2020.1832734

Sunny Yang Liu, Kohta Ikegami

引用次数: 34

The role of phosphorylation in the elasticity of the tethers that connect telomeres of separating anaphase chromosomes. 磷酸化在连接分离后期染色体端粒的系链弹性中的作用。

Nucleus (Austin, Tex.) Pub Date : 2020-12-01 DOI: 10.1080/19491034.2019.1710329

Emma Kite, Arthur Forer

引用次数: 5