The Experts below are selected from a list of 321 Experts worldwide ranked by ideXlab platform
Zuoyan Zhu - One of the best experts on this subject based on the ideXlab platform.
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Zebrafish z-otu, a novel Otu and Tudor domain-containing gene, is expressed in early stages of oogenesis and embryogenesis.
Biochimica et biophysica acta, 2005Co-Authors: Ping Song, Yungui Chen, Wei Zhou, Wuming Gong, Zuoyan ZhuAbstract:Several studies have suggested that Otu domain had de-ubiquitinating activity and Tudor domain was important for the formation of germ cells. Here, we reported a novel zebrafish ovary-specific gene containing Otu and Tudor domain, z-otu, which was expressed at stages I-III oocytes and embryonic stages from zygotes to early blastula during embryonic cells maintained their Totipotency. Therefore, z-otu might link the ubiquitin signaling pathway to early oogenesis and maintaining the Totipotency of embryonic cell.
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Zebrafish z-otu, a novel Otu and Tudor domain-containing gene, is expressed in early stages of oogenesis and embryogenesis
Biochimica et Biophysica Acta, 2005Co-Authors: Ping Song, Yungui Chen, Wei Zhou, Wuming Gong, Zuoyan ZhuAbstract:Several studies have suggested that Otu domain had de-ubiquitinating activity and Tudor domain was important for the formation of germ cells. Here, we reported a novel zebrafish ovary-specific gene containing Otu and Tudor domain, z-otu, which was expressed at stages I-III oocytes and embryonic stages from zygotes to early blastula during embryonic cells maintained their Totipotency. Therefore, z-otu might link the ubiquitin signaling pathway to early oogenesis and maintaining the Totipotency of embryonic cell. (c) 2005 Elsevier B.V. All rights reserved.
Maria-elena Torres-padilla - One of the best experts on this subject based on the ideXlab platform.
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On transposons and Totipotency.
Philosophical transactions of the Royal Society of London. Series B Biological sciences, 2020Co-Authors: Maria-elena Torres-padillaAbstract:Our perception of the role of the previously considered 'selfish' or 'junk' DNA has been dramatically altered in the past 20 years or so. A large proportion of this non-coding part of mammalian genomes is repetitive in nature, classified as either satellites or transposons. While repetitive elements can be termed selfish in terms of their amplification, such events have surely been co-opted by the host, suggesting by itself a likely altruistic function for the organism at the subject of such natural selection. Indeed numerous examples of transposons regulating the functional output of the host genome have been documented. Transposons provide a powerful framework for large-scale relatively rapid concerted regulatory activities with the ability to drive evolution. Mammalian Totipotency has emerged as one key stage of development in which transposon-mediated regulation of gene expression has taken centre stage in the past few years. During this period, large-scale (epigenetic) reprogramming must be accomplished in order to activate the host genome. In mice and men, one particular element murine endogenous retrovirus with leucine tRNA primer (MERVL) (and its counterpart human ERVL (HERVL)) appears to have acquired roles as a key driving force in this process. Here, I will discuss and interpret the current knowledge and its implications regarding the role of transposons, particularly of long interspersed nuclear elements (LINE-1s) and endogenous retroviruses (ERVs), in the regulation of Totipotency. This article is part of a discussion meeting issue 'Crossroads between transposons and gene regulation'.
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Building up the nucleus: nuclear organization in the establishment of Totipotency and pluripotency during mammalian development
Genes & development, 2016Co-Authors: Máté Borsos, Maria-elena Torres-padillaAbstract:In mammals, epigenetic reprogramming, the acquisition and loss of Totipotency, and the first cell fate decision all occur within a 3-d window after fertilization from the one-cell zygote to the formation of the blastocyst. These processes are poorly understood in molecular detail, yet this is an essential prerequisite to uncover principles of stem cells, chromatin biology, and thus regenerative medicine. A unique feature of preimplantation development is the drastic genome-wide changes occurring to nuclear architecture. From studying somatic and in vitro cultured embryonic stem cells (ESCs) it is becoming increasingly established that the three-dimensional (3D) positions of genomic loci relative to each other and to specific compartments of the nucleus can act on the regulation of gene expression, potentially driving cell fate. However, the functionality, mechanisms, and molecular characteristics of the changes in nuclear organization during preimplantation development are only now beginning to be unraveled. Here, we discuss the peculiarities of nuclear compartments and chromatin organization during mammalian preimplantation development in the context of the transition from Totipotency to pluripotency.
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Higher chromatin mobility supports Totipotency and precedes pluripotency in vivo
Genes & development, 2014Co-Authors: Ana Bošković, Takashi Ishiuchi, André Eid, Julien Pontabry, Coralie Spiegelhalter, Edupuganti V.s. Raghu Ram, Eran Meshorer, Maria-elena Torres-padillaAbstract:The fusion of the gametes upon fertilization results in the formation of a totipotent cell. Embryonic chromatin is expected to be able to support a large degree of plasticity. However, whether this plasticity relies on a particular conformation of the embryonic chromatin is unknown. Moreover, whether chromatin plasticity is functionally linked to cellular potency has not been addressed. Here, we adapted fluorescence recovery after photobleaching (FRAP) in the developing mouse embryo and show that mobility of the core histones H2A, H3.1, and H3.2 is unusually high in two-cell stage embryos and decreases as development proceeds. The transition toward pluripotency is accompanied by a decrease in histone mobility, and, upon lineage allocation, pluripotent cells retain higher mobility than the differentiated trophectoderm. Importantly, totipotent two-cell-like embryonic stem cells also display high core histone mobility, implying that reprogramming toward Totipotency entails changes in chromatin mobility. Our data suggest that changes in chromatin dynamics underlie the transitions in cellular plasticity and that higher chromatin mobility is at the nuclear foundations of Totipotency.
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Towards an understanding of the regulatory mechanisms of Totipotency.
Current opinion in genetics & development, 2013Co-Authors: Takashi Ishiuchi, Maria-elena Torres-padillaAbstract:The 21st century started with an important discovery that a pluripotent stem cell can be induced from differentiated cells by ‘simply’ introducing a few transcription factors. Because pluripotent embryonic stem cells can be stably maintained in culture and also induced, the mechanisms as to how cells maintain and acquire pluripotency have been extensively interrogated. In contrast, how cells maintain or acquire Totipotency and the cell potency that exists in the zygote are still poorly understood. To address this question, it is necessary to capture the features that reside in totipotent cells. Here, we review recent results, which shed light on the unique epigenetic state in totipotent cells, and discuss how Totipotency is regulated before finding its way towards pluripotency.
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A germline-centric view of cell fate commitment, reprogramming and immortality.
Development (Cambridge England), 2013Co-Authors: Maria-elena Torres-padilla, Rafal CioskAbstract:Summary To ensure species continuity, the tantalising developmental plasticity of early embryonic cells, also called Totipotency, must be transmitted to the offspring. This responsibility rests within the reproductive cell lineage: the germ line. At the recent EMBO/EMBL symposium ‘Germline – Immortality through Totipotency’, researchers discussed the mechanisms that establish and control Totipotency, with an eye towards the mechanisms that may endow germ cells with the ability to propagate Totipotency across generations.
Yves Chupeau - One of the best experts on this subject based on the ideXlab platform.
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Characterization of the Early Events Leading to Totipotency in an Arabidopsis Protoplast Liquid Culture by Temporal Transcript Profiling
The Plant cell, 2013Co-Authors: Marie-christine Chupeau, Fabienne Granier, Olivier Pichon, Jean-pierre Renou, Valérie Gaudin, Yves ChupeauAbstract:The molecular mechanisms underlying plant cell Totipotency are largely unknown. Here, we present a protocol for the efficient regeneration of plants from Arabidopsis thaliana protoplasts. The specific liquid medium used in our study leads to a high rate of reentry into the cell cycle of most cell types, providing a powerful system to study dedifferentiation/regeneration processes in independent somatic cells. To identify the early events in the establishment of Totipotency, we monitored the genome-wide transcript profiles of plantlets and protoplast-derived cells (PdCs) during the first week of culture. Plant cells rapidly dedifferentiated. Then, we observed the reinitiation and reorientation of protein synthesis, accompanied by the reinitiation of cell division and de novo cell wall synthesis. Marked changes in the expression of chromatin-associated genes, especially of those in the histone variant family, were observed during protoplast culture. Surprisingly, the epigenetic status of PdCs and well-established cell cultures differed, with PdCs exhibiting rare reactivated transposons and epigenetic changes. The differentially expressed genes identified in this study are interesting candidates for investigating the molecular mechanisms underlying plant cell plasticity and Totipotency. One of these genes, the plant-specific transcription factor ABERRANT LATERAL ROOT FORMATION4, is required for the initiation of protoplast division.
Ping Song - One of the best experts on this subject based on the ideXlab platform.
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Zebrafish z-otu, a novel Otu and Tudor domain-containing gene, is expressed in early stages of oogenesis and embryogenesis.
Biochimica et biophysica acta, 2005Co-Authors: Ping Song, Yungui Chen, Wei Zhou, Wuming Gong, Zuoyan ZhuAbstract:Several studies have suggested that Otu domain had de-ubiquitinating activity and Tudor domain was important for the formation of germ cells. Here, we reported a novel zebrafish ovary-specific gene containing Otu and Tudor domain, z-otu, which was expressed at stages I-III oocytes and embryonic stages from zygotes to early blastula during embryonic cells maintained their Totipotency. Therefore, z-otu might link the ubiquitin signaling pathway to early oogenesis and maintaining the Totipotency of embryonic cell.
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Zebrafish z-otu, a novel Otu and Tudor domain-containing gene, is expressed in early stages of oogenesis and embryogenesis
Biochimica et Biophysica Acta, 2005Co-Authors: Ping Song, Yungui Chen, Wei Zhou, Wuming Gong, Zuoyan ZhuAbstract:Several studies have suggested that Otu domain had de-ubiquitinating activity and Tudor domain was important for the formation of germ cells. Here, we reported a novel zebrafish ovary-specific gene containing Otu and Tudor domain, z-otu, which was expressed at stages I-III oocytes and embryonic stages from zygotes to early blastula during embryonic cells maintained their Totipotency. Therefore, z-otu might link the ubiquitin signaling pathway to early oogenesis and maintaining the Totipotency of embryonic cell. (c) 2005 Elsevier B.V. All rights reserved.
Fanchang Zeng - One of the best experts on this subject based on the ideXlab platform.
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Dynamic TMT-Based Quantitative Proteomics Analysis of Critical Initiation Process of Totipotency during Cotton Somatic Embryogenesis Transdifferentiation.
International journal of molecular sciences, 2019Co-Authors: Haixia Guo, Huihui Guo, Li Zhang, Yijie Fan, Yupeng Fan, Zhengmin Tang, Fanchang ZengAbstract:The somatic embryogenesis (SE) process of plants, as one of the typical responses to abiotic stresses with hormone, occurs through the dynamic expression of different proteins that constitute a complex regulatory network in biological activities and promotes plant Totipotency. Plant SE includes two critical stages: primary embryogenic calli redifferentiation and somatic embryos development initiation, which leads to Totipotency. The isobaric labels tandem mass tags (TMT) large-scale and quantitative proteomics technique was used to identify the dynamic protein expression changes in nonembryogenic calli (NEC), primary embryogenic calli (PEC) and globular embryos (GEs) of cotton. A total of 9369 proteins (6730 quantified) were identified; 805, 295 and 1242 differentially accumulated proteins (DAPs) were identified in PEC versus NEC, GEs versus PEC and GEs versus NEC, respectively. Eight hundred and five differentially abundant proteins were identified, 309 of which were upregulated and 496 down regulated in PEC compared with NEC. Of the 295 DAPs identified between GEs and PEC, 174 and 121 proteins were up- and down regulated, respectively. Of 1242 differentially abundant proteins, 584 and 658 proteins were up- and down regulated, respectively, in GEs versus NEC. We have also complemented the authenticity and accuracy of the proteomic analysis. Systematic analysis indicated that peroxidase, photosynthesis, environment stresses response processes, nitrogen metabolism, phytohormone response/signal transduction, transcription/posttranscription and modification were involved in somatic embryogenesis. The results generated in this study demonstrate a proteomic molecular basis and provide a valuable foundation for further investigation of the roles of DAPs in the process of SE transdifferentiation during cotton Totipotency.
