Differentiated nuclei can be reprogrammed/remodelled to totipotency after their transfer to enucleated metaphase II (MII) oocytes. The process of reprogramming/remodelling is, however, only partially characterized. It has been shown that the oocyte nucleus (germinal vesicle - GV) components are essential for a successful remodelling of the transferred nucleus by providing the materials for pseudo-nucleus formation. However, the nucleus is a complex structure and exactly what nuclear components are required for a successful nucleus remodelling and reprogramming is unknown. Till date, the only nuclear sub-structure experimentally demonstrated to be essential is the oocyte nucleolus (nucleolus-like body, NLB). In this study, we investigated what other GV components might be necessary for the formation of normal-sized pseudo-pronuclei (PNs). Our results showed that the removal of the GV nuclear envelope with attached chromatin and chromatin-bound factors does not substantially influence the size of the remodelled nuclei in reconstructed cells and that their nuclear envelopes seem to have normal parameters. Rather than the insoluble nuclear lamina, the GV content, which is dissolved in the cytoplasm with the onset of oocyte maturation, influences the characteristics and size of transferred nuclei.
- MeSH
- Cell Nucleolus metabolism MeSH
- Cell Nucleus metabolism MeSH
- Chromatin metabolism MeSH
- Cytoplasm metabolism MeSH
- Nuclear Lamina metabolism MeSH
- Nuclear Envelope metabolism MeSH
- RNA, Messenger metabolism MeSH
- Mice MeSH
- Oocytes cytology metabolism MeSH
- Oogenesis MeSH
- Ovarian Follicle metabolism MeSH
- Cellular Reprogramming * MeSH
- Nuclear Transfer Techniques * MeSH
- Animals MeSH
- Check Tag
- Mice MeSH
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
Objev indukované pluripotence v roce 2006 umožnil revoluční způsob získávaní autologních terapeuticky aplikovatelných buněk, a mož‐ nost modelovat jakékoliv onemocnění v in vitro podmínkách. Možnost vrátit libovolnou, finálně diferencovanou buňku „v čase“ zpátky do stádia pluripotence je zajímavé i pro oblast onkologického výzkumu. Tato technologie umožnila studium procesů spojených s roz‐ vojem nádorového fenotypu buňky a taky s přechodem nádorové buňky do stádia s nižší mírou diferenciace. Reprogramování buněk do indukovaných pluripotentních kmenových buněk také pomáhá mnohem lépe studovat raritní populaci buněk, přítomných v nádo‐ rech – tzv. nádorové kmenové buňky. Indukovaná pluripotence některých typů nádorových buněk, spojená s jejich následnou řízenou diferenciací by se zároveň mohla stát jednou z možných terapeutických aplikací v onkologii.
Discovery of technology of induced pluripotency that allows the generation of autologous therapeutically applicable cells and generati‐ on of in vitro cell models for diseases with limited (or highly invasive) access to tested cells has also opened new horizons in the field of oncology research. The unique ability to reprogram the cancer cell into pluripotency with subsequent directed differentiation into cell with no malignant phenotype should be considered as a challenge in the field of new oncotherapy development. Although still conside‐ red to be realistic only on the level of experimental approach, the recent progress in the field of induced pluripotency gives the hope that dedifferentiation‐based therapies connected with the erase of malignant phenotype of original cancer cell will be more realistic in near future. By then, the most important role of induced pluripotency in oncology remains in the field of regenerative therapy as a source of autologous cells for regeneration of tissues or organs damaged by tumor growth or aggressive therapy
It is now more than nine years since Dolly, the world's first somatic cell cloned mammal was born, and the success of somatic cell nuclear transfer (SCNT) is still disappointingly low. Only about 3-5% of reconstructed embryos develop to term, and it is also evident that even if some clones are born, they are not necessarily fully developed and healthy. Embryonic and neonatal abnormalities of cloned offspring are probably a result of incorrect or incomplete reprogramming of the transferred donor cell nuclei. Such an incomplete reprogramming reflects the extremely low efficiency of SCNT. The key role in the process of reprogramming has been attributed to the enucleated oocyte-cytoplast into which the somatic cell nucleus is transferred. In our chapter, we will discuss the methodological approaches used for the preparation of cytoplasts and their possible reprogramming activities.
- MeSH
- Cell Differentiation genetics MeSH
- Cell Nucleus genetics MeSH
- Cytoplasmic Structures metabolism MeSH
- Embryonic Development genetics MeSH
- Financing, Organized MeSH
- Histones genetics MeSH
- Cloning, Organism methods trends MeSH
- Humans MeSH
- Oocytes metabolism MeSH
- Chromatin Assembly and Disassembly genetics MeSH
- Nuclear Transfer Techniques standards trends MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Animals MeSH
Novartis foundation symposium ; 265
viii, 221 s. : il. ; 24 cm
Aim: Human induced pluripotent stem cells (iPSCs) are inefficiently derived from somatic cells by overexpression of defined transcription factors. Overexpression of H2A histone variant macroH2A1.1, but not macroH2A1.2, leads to increased iPSC reprogramming by unclear mechanisms. Materials & methods: Cleavage under targets and tagmentation (CUT&Tag) allows robust epigenomic profiling of a low cell number. We performed an integrative CUT&Tag-RNA-Seq analysis of macroH2A1-dependent orchestration of iPSCs reprogramming using human endothelial cells. Results: We demonstrate wider genome occupancy, predicted transcription factors binding, and gene expression regulated by macroH2A1.1 during reprogramming, compared to macroH2A1.2. MacroH2A1.1, previously associated with neurodegenerative pathologies, specifically activated ectoderm/neural processes. Conclusion: CUT&Tag and RNA-Seq data integration is a powerful tool to investigate the epigenetic mechanisms occurring during cell reprogramming.
- MeSH
- Endothelial Cells metabolism MeSH
- Histones * metabolism MeSH
- Induced Pluripotent Stem Cells * metabolism MeSH
- Humans MeSH
- Cellular Reprogramming genetics MeSH
- RNA-Seq MeSH
- Transcription Factors genetics MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
The authors of the article titled "Advances in Genetic Reprogramming: Prospects from Developmental Biology to Regenerative Medicine" (Dhanjal DS, Singh R, Sharma V, Nepovimova E, Adam V, Kuca K, Chopra C. Curr Med Chem. 2024; 31(13): 1646-1690. DOI: 10.2174/0929867330666230503144619. PMID: 37138422) [1] have made revisions to the references in the text and the reference section. These updates have been made to ensure the integrity of the article. The updated reference list can be found in the latest version of the article. The authors apologize for any confusion or inconvenience caused. The original article can be found online at: https://www.eurekaselect.com/article/131443.
- MeSH
- Humans MeSH
- Cellular Reprogramming * genetics MeSH
- Regenerative Medicine * MeSH
- Developmental Biology MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Review MeSH
The foundations of cell reprogramming were laid by Yamanaka and co-workers, who showed that somatic cells can be reprogrammed into pluripotent cells (induced pluripotency). Since this discovery, the field of regenerative medicine has seen advancements. For example, because they can differentiate into multiple cell types, pluripotent stem cells are considered vital components in regenerative medicine aimed at the functional restoration of damaged tissue. Despite years of research, both replacement and restoration of failed organs/ tissues have remained elusive scientific feats. However, with the inception of cell engineering and nuclear reprogramming, useful solutions have been identified to counter the need for compatible and sustainable organs. By combining the science underlying genetic engineering and nuclear reprogramming with regenerative medicine, scientists have engineered cells to make gene and stem cell therapies applicable and effective. These approaches have enabled the targeting of various pathways to reprogramme cells, i.e., make them behave in beneficial ways in a patient-specific manner. Technological advancements have clearly supported the concept and realization of regenerative medicine. Genetic engineering is used for tissue engineering and nuclear reprogramming and has led to advances in regenerative medicine. Targeted therapies and replacement of traumatized , damaged, or aged organs can be realized through genetic engineering. Furthermore, the success of these therapies has been validated through thousands of clinical trials. Scientists are currently evaluating induced tissue-specific stem cells (iTSCs), which may lead to tumour-free applications of pluripotency induction. In this review, we present state-of-the-art genetic engineering that has been used in regenerative medicine. We also focus on ways that genetic engineering and nuclear reprogramming have transformed regenerative medicine and have become unique therapeutic niches.
- MeSH
- Genetic Engineering MeSH
- Induced Pluripotent Stem Cells metabolism cytology MeSH
- Humans MeSH
- Cellular Reprogramming * MeSH
- Regenerative Medicine * MeSH
- Tissue Engineering MeSH
- Developmental Biology MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Review MeSH
Reprogramming to pluripotency is associated with DNA damage and requires the functions of the BRCA1 tumor suppressor. Here, we leverage separation-of-function mutations in BRCA1/2 as well as the physical and/or genetic interactions between BRCA1 and its associated repair proteins to ascertain the relevance of homology-directed repair (HDR), stalled fork protection (SFP), and replication gap suppression (RGS) in somatic cell reprogramming. Surprisingly, loss of SFP and RGS is inconsequential for the transition to pluripotency. In contrast, cells deficient in HDR, but proficient in SFP and RGS, reprogram with reduced efficiency. Conversely, the restoration of HDR function through inactivation of 53bp1 rescues reprogramming in Brca1-deficient cells, and 53bp1 loss leads to elevated HDR and enhanced reprogramming in mouse and human cells. These results demonstrate that somatic cell reprogramming is especially dependent on repair of replication-associated double-strand breaks (DSBs) by the HDR activity of BRCA1 and BRCA2 and can be improved in the absence of 53BP1.
- MeSH
- Tumor Suppressor p53-Binding Protein 1 * metabolism genetics MeSH
- DNA Breaks, Double-Stranded * MeSH
- Humans MeSH
- Mice MeSH
- DNA Repair * MeSH
- Cellular Reprogramming * MeSH
- BRCA1 Protein * metabolism genetics MeSH
- Recombinational DNA Repair MeSH
- DNA Replication MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Mice MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Research Support, N.I.H., Extramural MeSH
Significance: The architecture of the mitochondrial network and cristae critically impact cell differentiation and identity. Cells undergoing metabolic reprogramming to aerobic glycolysis (Warburg effect), such as immune cells, stem cells, and cancer cells, go through controlled modifications in mitochondrial architecture, which is critical for achieving the resulting cellular phenotype. Recent Advances: Recent studies in immunometabolism have shown that the manipulation of mitochondrial network dynamics and cristae shape directly affects T cell phenotype and macrophage polarization through altering energy metabolism. Similar manipulations also alter the specific metabolic phenotypes that accompany somatic reprogramming, stem cell differentiation, and cancer cells. The modulation of oxidative phosphorylation activity, accompanied by changes in metabolite signaling, reactive oxygen species generation, and adenosine triphosphate levels, is the shared underlying mechanism. Critical Issues: The plasticity of mitochondrial architecture is particularly vital for metabolic reprogramming. Consequently, failure to adapt the appropriate mitochondrial morphology often compromises the differentiation and identity of the cell. Immune, stem, and tumor cells exhibit striking similarities in their coordination of mitochondrial morphology with metabolic pathways. However, although many general unifying principles can be observed, their validity is not absolute, and the mechanistic links thus need to be further explored. Future Directions: Better knowledge of the molecular mechanisms involved and their relationships to both mitochondrial network and cristae morphology will not only further deepen our understanding of energy metabolism but may also contribute to improved therapeutic manipulation of cell viability, differentiation, proliferation, and identity in many different cell types. Antioxid. Redox Signal. 39, 684-707.
