Pub Date : 2013-01-01Epub Date: 2013-12-02DOI: 10.1155/2013/495724
Carla Luana Dinardo, Paulo Caleb Junior Lima Santos, Isolmar Tadeu Schettert, Renata Alonso Gadi Soares, Jose Eduardo Krieger, Alexandre Costa Pereira
Background. Idiopathic erythrocytosis is the term reserved for cases with unexplained origins of abnormally increased hemoglobin after initial investigation. Extensive molecular investigation of genes associated with oxygen sensing and erythropoietin signaling pathways, in those cases, usually involves sequencing all of their exons and it may be time consuming. Aim. To perform a strategy for molecular investigation of patients with idiopathic erythrocytosis regarding oxygen sensing and erythropoietin signaling pathways. Methods. Samples of patients with idiopathic erythrocytosis were evaluated for the EPOR, VHL, PHD2, and HIF-2 α genes using bidirectional sequencing of their hotspots. Results. One case was associated with HIF-2 α mutation. Sequencing did not identify any pathogenic mutation in 4 of 5 cases studied in any of the studied genes. Three known nonpathogenic polymorphisms were found (VHL p.P25L, rs35460768; HIF-2 α p.N636N, rs35606117; HIF-2 α p.P579P, rs184760160). Conclusion. Extensive molecular investigation of cases considered as idiopathic erythrocytosis does not frequently change the treatment of the patient. However, we propose a complementary molecular investigation of those cases comprising genes associated with erythrocytosis phenotype to meet both academic and genetic counseling purposes.
{"title":"Investigation of genetic disturbances in oxygen sensing and erythropoietin signaling pathways in cases of idiopathic erythrocytosis.","authors":"Carla Luana Dinardo, Paulo Caleb Junior Lima Santos, Isolmar Tadeu Schettert, Renata Alonso Gadi Soares, Jose Eduardo Krieger, Alexandre Costa Pereira","doi":"10.1155/2013/495724","DOIUrl":"https://doi.org/10.1155/2013/495724","url":null,"abstract":"<p><p>Background. Idiopathic erythrocytosis is the term reserved for cases with unexplained origins of abnormally increased hemoglobin after initial investigation. Extensive molecular investigation of genes associated with oxygen sensing and erythropoietin signaling pathways, in those cases, usually involves sequencing all of their exons and it may be time consuming. Aim. To perform a strategy for molecular investigation of patients with idiopathic erythrocytosis regarding oxygen sensing and erythropoietin signaling pathways. Methods. Samples of patients with idiopathic erythrocytosis were evaluated for the EPOR, VHL, PHD2, and HIF-2 α genes using bidirectional sequencing of their hotspots. Results. One case was associated with HIF-2 α mutation. Sequencing did not identify any pathogenic mutation in 4 of 5 cases studied in any of the studied genes. Three known nonpathogenic polymorphisms were found (VHL p.P25L, rs35460768; HIF-2 α p.N636N, rs35606117; HIF-2 α p.P579P, rs184760160). Conclusion. Extensive molecular investigation of cases considered as idiopathic erythrocytosis does not frequently change the treatment of the patient. However, we propose a complementary molecular investigation of those cases comprising genes associated with erythrocytosis phenotype to meet both academic and genetic counseling purposes. </p>","PeriodicalId":37545,"journal":{"name":"Genetics Research International","volume":"2013 ","pages":"495724"},"PeriodicalIF":0.0,"publicationDate":"2013-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2013/495724","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"31976285","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}
Pub Date : 2013-01-01Epub Date: 2013-12-23DOI: 10.1155/2013/724124
Yunbo Xu, Hongliang Hu, Jie Zheng, Biaoru Li
Single-cell sampling with RNA-seq analysis plays an important role in reference laboratory; cytogenomic diagnosis for specimens on glass-slides or rare cells in circulating blood for tumor and genetic diseases; measurement of sensitivity and specificity in tumor-tissue genomic analysis with mixed-cells; mechanism analysis of differentiation and proliferation of cancer stem cell for academic purpose. Our single- cell RNA-seq technique shows that fragments were 250-450 bp after fragmentation, amplification, and adapter addition. There were 11.6 million reads mapped in raw sequencing reads (19.6 million). The numbers of mapped genes, mapped transcripts, and mapped exons were 31,332, 41,210, and 85,786, respectively. All QC results demonstrated that RNA-seq techniques could be used for single-cell genomic performance. Analysis of the mapped genes showed that the number of genes mapped by RNA-seq (6767 genes) was much higher than that of differential display (288 libraries) among similar specimens which we have developed and published. The single-cell RNA-seq can detect gene splicing using different subtype TGF-beta analysis. The results from using Q-rtPCR tests demonstrated that sensitivity is 76% and specificity is 55% from single-cell RNA-seq technique with some gene expression missing (2/8 genes). However, it will be feasible to use RNA-seq techniques to contribute to genomic medicine at single-cell level.
{"title":"Feasibility of whole RNA sequencing from single-cell mRNA amplification.","authors":"Yunbo Xu, Hongliang Hu, Jie Zheng, Biaoru Li","doi":"10.1155/2013/724124","DOIUrl":"10.1155/2013/724124","url":null,"abstract":"<p><p>Single-cell sampling with RNA-seq analysis plays an important role in reference laboratory; cytogenomic diagnosis for specimens on glass-slides or rare cells in circulating blood for tumor and genetic diseases; measurement of sensitivity and specificity in tumor-tissue genomic analysis with mixed-cells; mechanism analysis of differentiation and proliferation of cancer stem cell for academic purpose. Our single- cell RNA-seq technique shows that fragments were 250-450 bp after fragmentation, amplification, and adapter addition. There were 11.6 million reads mapped in raw sequencing reads (19.6 million). The numbers of mapped genes, mapped transcripts, and mapped exons were 31,332, 41,210, and 85,786, respectively. All QC results demonstrated that RNA-seq techniques could be used for single-cell genomic performance. Analysis of the mapped genes showed that the number of genes mapped by RNA-seq (6767 genes) was much higher than that of differential display (288 libraries) among similar specimens which we have developed and published. The single-cell RNA-seq can detect gene splicing using different subtype TGF-beta analysis. The results from using Q-rtPCR tests demonstrated that sensitivity is 76% and specificity is 55% from single-cell RNA-seq technique with some gene expression missing (2/8 genes). However, it will be feasible to use RNA-seq techniques to contribute to genomic medicine at single-cell level. </p>","PeriodicalId":37545,"journal":{"name":"Genetics Research International","volume":"2013 ","pages":"724124"},"PeriodicalIF":0.0,"publicationDate":"2013-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3885331/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"32055285","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}
Pub Date : 2013-01-01Epub Date: 2013-02-19DOI: 10.1155/2013/852080
Chiranjeevi Sandi, Sahar Al-Mahdawi, Mark A Pook
Friedreich's ataxia (FRDA) is an autosomal recessive neurodegenerative disorder caused by homozygous expansion of a GAA·TTC trinucleotide repeat within the first intron of the FXN gene, leading to reduced FXN transcription and decreased levels of frataxin protein. Recent advances in FRDA research have revealed the presence of several epigenetic modifications that are either directly or indirectly involved in this FXN gene silencing. Although epigenetic marks may be inherited from one generation to the next, modifications of DNA and histones can be reversed, indicating that they are suitable targets for epigenetic-based therapy. Unlike other trinucleotide repeat disorders, such as Huntington disease, the large expansions of GAA·TTC repeats in FRDA do not produce a change in the frataxin amino acid sequence, but they produce reduced levels of normal frataxin. Therefore, transcriptional reactivation of the FXN gene provides a good therapeutic option. The present paper will initially focus on the epigenetic changes seen in FRDA patients and their role in the silencing of FXN gene and will be concluded by considering the potential epigenetic therapies.
{"title":"Epigenetics in Friedreich's Ataxia: Challenges and Opportunities for Therapy.","authors":"Chiranjeevi Sandi, Sahar Al-Mahdawi, Mark A Pook","doi":"10.1155/2013/852080","DOIUrl":"https://doi.org/10.1155/2013/852080","url":null,"abstract":"<p><p>Friedreich's ataxia (FRDA) is an autosomal recessive neurodegenerative disorder caused by homozygous expansion of a GAA·TTC trinucleotide repeat within the first intron of the FXN gene, leading to reduced FXN transcription and decreased levels of frataxin protein. Recent advances in FRDA research have revealed the presence of several epigenetic modifications that are either directly or indirectly involved in this FXN gene silencing. Although epigenetic marks may be inherited from one generation to the next, modifications of DNA and histones can be reversed, indicating that they are suitable targets for epigenetic-based therapy. Unlike other trinucleotide repeat disorders, such as Huntington disease, the large expansions of GAA·TTC repeats in FRDA do not produce a change in the frataxin amino acid sequence, but they produce reduced levels of normal frataxin. Therefore, transcriptional reactivation of the FXN gene provides a good therapeutic option. The present paper will initially focus on the epigenetic changes seen in FRDA patients and their role in the silencing of FXN gene and will be concluded by considering the potential epigenetic therapies.</p>","PeriodicalId":37545,"journal":{"name":"Genetics Research International","volume":" ","pages":"852080"},"PeriodicalIF":0.0,"publicationDate":"2013-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2013/852080","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40228640","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}
Pub Date : 2013-01-01Epub Date: 2013-12-31DOI: 10.1155/2013/249157
H Direskeneli
Behcet's disease (BD) is a systemic, chronic inflammatory disorder with both innate and adaptive immune responses. Heat shock proteins (HSP) are highly conserved molecules in different species with scavenger activity and involved in correct folding of newly synthesized proteins. T and B cell responses against HSPs are observed in BD patients in both αβ and γδ T-cell populations. 60-kD HSP (HSP60) is also shown to be recognized by pattern recognition receptors such as toll-like receptors (TLR) and is suggested to be an endogenous "danger" signal to the immune system with rapid inflammatory cytokine releases and enhancement of adaptive Th1-type responses. Elucidating the exact role of HSPs in BD pathogenesis might pave the way to less toxic therapeutic approaches to BD, such as antibacterial therapies and immunomodulation.
{"title":"Innate and Adaptive Responses to Heat Shock Proteins in Behcet's Disease.","authors":"H Direskeneli","doi":"10.1155/2013/249157","DOIUrl":"https://doi.org/10.1155/2013/249157","url":null,"abstract":"<p><p>Behcet's disease (BD) is a systemic, chronic inflammatory disorder with both innate and adaptive immune responses. Heat shock proteins (HSP) are highly conserved molecules in different species with scavenger activity and involved in correct folding of newly synthesized proteins. T and B cell responses against HSPs are observed in BD patients in both αβ and γδ T-cell populations. 60-kD HSP (HSP60) is also shown to be recognized by pattern recognition receptors such as toll-like receptors (TLR) and is suggested to be an endogenous \"danger\" signal to the immune system with rapid inflammatory cytokine releases and enhancement of adaptive Th1-type responses. Elucidating the exact role of HSPs in BD pathogenesis might pave the way to less toxic therapeutic approaches to BD, such as antibacterial therapies and immunomodulation. </p>","PeriodicalId":37545,"journal":{"name":"Genetics Research International","volume":"2013 ","pages":"249157"},"PeriodicalIF":0.0,"publicationDate":"2013-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2013/249157","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"32085462","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}
Pub Date : 2012-01-01Epub Date: 2012-11-28DOI: 10.1155/2012/491204
Vett K Lloyd, Jennifer A Brisson, Kathleen A Fitzpatrick, Lori A McEachern, Eveline C Verhulst
Genetic model organisms have gifted researchers with a breathtakingly detailed understanding of the most intimate aspects of their genomes, cells, and development. And yet there is a problem—model organisms have been selected because they have simple life histories and happily inhabit laboratories. In short, they make a virtue of being boring. But the diversity of the natural world is not fully captured by yeast, flies, or mice. To truly appreciate the variety of biological mechanisms underlying this remarkable diversity, one must study the often inconvenient but fascinating non-model organism. Experimental and descriptive approaches in nonmodel organisms have become more tractable with reduced genome-sequencing costs and the transferability of techniques and tools developed in model organisms, elevating some of them from non-model to emerging model organism status. One area of biology into which non-model organisms promise to provide significant insight is the area of epigenetics. Epigenetics focuses on how internal and external environments interact with the genome to produce the phenotype, and non-model organisms arguably present a larger range of phenotypes than model organisms. In this issue, we present recent research into the epigenetics of non- and emerging-model organisms. The papers in this series highlight several common themes: experimental approaches to studying epigenetics in non-model organisms, epigenetics as a mediator of environmental changes in morphology and development, and epigenetic contributions to individual and population diversity. How to Study Epigenetics in Non- and Emerging-Model Organisms — Despite the ecological and evolutionary importance of non-model organisms, an obvious disadvantage is the absence of genetic and epigenetic tools available for these organisms. This issue is addressed by W. A. MacDonald, who examines the question of whether one of the best-studied aspects of epigenetics, genomic imprinting, is evolutionarily conserved. His conclusion that the basic epigenetic mechanisms, if not the target genes, are conserved, allows the extrapolation of findings from model organisms to non-model organisms. This approach is taken by studies on polychaetes (G. Gibson et al.) and Daphnia (N. F. Robichaud et al.) in this special issue. L. A. McEachern further explores the potential of transgenic epigenetic studies in non-model organism research. This underutilized but powerful and sophisticated approach to studying epigenetics involves transferring a potential epigenetic control sequence from one organism to another for detailed molecular analysis. On a practical level, G. Prantera and S. Bongiorni examine new experimental approaches used to dissect one of the first epigenetic processes described, chromosome imprinting in mealybugs, and K. R. Shorter et al. describe the manifold resources for the study of the deer mouse Peromyscus, by the Peromyscus genome center. Epigenetics as
{"title":"The epigenetics of emerging and nonmodel organisms.","authors":"Vett K Lloyd, Jennifer A Brisson, Kathleen A Fitzpatrick, Lori A McEachern, Eveline C Verhulst","doi":"10.1155/2012/491204","DOIUrl":"https://doi.org/10.1155/2012/491204","url":null,"abstract":"Genetic model organisms have gifted researchers with a breathtakingly detailed understanding of the most intimate aspects of their genomes, cells, and development. And yet there is a problem—model organisms have been selected because they have simple life histories and happily inhabit laboratories. In short, they make a virtue of being boring. But the diversity of the natural world is not fully captured by yeast, flies, or mice. To truly appreciate the variety of biological mechanisms underlying this remarkable diversity, one must study the often inconvenient but fascinating non-model organism. Experimental and descriptive approaches in nonmodel organisms have become more tractable with reduced genome-sequencing costs and the transferability of techniques and tools developed in model organisms, elevating some of them from non-model to emerging model organism status. \u0000 \u0000One area of biology into which non-model organisms promise to provide significant insight is the area of epigenetics. Epigenetics focuses on how internal and external environments interact with the genome to produce the phenotype, and non-model organisms arguably present a larger range of phenotypes than model organisms. In this issue, we present recent research into the epigenetics of non- and emerging-model organisms. The papers in this series highlight several common themes: experimental approaches to studying epigenetics in non-model organisms, epigenetics as a mediator of environmental changes in morphology and development, and epigenetic contributions to individual and population diversity. \u0000 \u0000 \u0000 \u0000 \u0000 \u0000 \u0000How to Study Epigenetics in Non- and Emerging-Model Organisms — \u0000Despite the ecological and evolutionary importance of non-model organisms, an obvious disadvantage is the absence of genetic and epigenetic tools available for these organisms. This issue is addressed by W. A. MacDonald, who examines the question of whether one of the best-studied aspects of epigenetics, genomic imprinting, is evolutionarily conserved. His conclusion that the basic epigenetic mechanisms, if not the target genes, are conserved, allows the extrapolation of findings from model organisms to non-model organisms. This approach is taken by studies on polychaetes (G. Gibson et al.) and Daphnia (N. F. Robichaud et al.) in this special issue. L. A. McEachern further explores the potential of transgenic epigenetic studies in non-model organism research. This underutilized but powerful and sophisticated approach to studying epigenetics involves transferring a potential epigenetic control sequence from one organism to another for detailed molecular analysis. On a practical level, G. Prantera and S. Bongiorni examine new experimental approaches used to dissect one of the first epigenetic processes described, chromosome imprinting in mealybugs, and K. R. Shorter et al. describe the manifold resources for the study of the deer mouse Peromyscus, by the Peromyscus genome center. \u0000 \u0000 \u0000 \u0000 \u0000 \u0000 \u0000 \u0000 \u0000 \u0000 \u0000Epigenetics as","PeriodicalId":37545,"journal":{"name":"Genetics Research International","volume":"2012 ","pages":"491204"},"PeriodicalIF":0.0,"publicationDate":"2012-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2012/491204","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"31126933","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}
Pub Date : 2012-01-01Epub Date: 2012-12-04DOI: 10.1155/2012/748698
Joel Sng, Thomas Lufkin
The inner ear cytoarchitecture forms one of the most intricate and delicate organs in the human body and is vulnerable to the effects of genetic disorders, aging, and environmental damage. Owing to the inability of the mammalian cochlea to regenerate sensory hair cells, the loss of hair cells is a leading cause of deafness in humans. Millions of individuals worldwide are affected by the emotionally and financially devastating effects of hearing impairment (HI). This paper provides a brief introduction into the key role of genes regulating inner ear development and function. Potential future therapies that leverage on an improved understanding of these molecular pathways are also described in detail.
{"title":"Filling the silent void: genetic therapies for hearing impairment.","authors":"Joel Sng, Thomas Lufkin","doi":"10.1155/2012/748698","DOIUrl":"https://doi.org/10.1155/2012/748698","url":null,"abstract":"<p><p>The inner ear cytoarchitecture forms one of the most intricate and delicate organs in the human body and is vulnerable to the effects of genetic disorders, aging, and environmental damage. Owing to the inability of the mammalian cochlea to regenerate sensory hair cells, the loss of hair cells is a leading cause of deafness in humans. Millions of individuals worldwide are affected by the emotionally and financially devastating effects of hearing impairment (HI). This paper provides a brief introduction into the key role of genes regulating inner ear development and function. Potential future therapies that leverage on an improved understanding of these molecular pathways are also described in detail.</p>","PeriodicalId":37545,"journal":{"name":"Genetics Research International","volume":"2012 ","pages":"748698"},"PeriodicalIF":0.0,"publicationDate":"2012-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2012/748698","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"31147996","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}
Pub Date : 2012-01-01Epub Date: 2012-01-29DOI: 10.1155/2012/430136
Patrick M Ferree, Satyaki Prasad
Satellites are one of the most enigmatic parts of the eukaryotic genome. These highly repetitive, noncoding sequences make up as much as half or more of the genomic content and are known to play essential roles in chromosome segregation during meiosis and mitosis, yet they evolve rapidly between closely related species. Research over the last several decades has revealed that satellite divergence can serve as a formidable reproductive barrier between sibling species. Here we highlight several key studies on Drosophila and other model organisms demonstrating deleterious effects of satellites and their rapid evolution on the structure and function of chromosomes in interspecies hybrids. These studies demonstrate that satellites can impact chromosomes at a number of different developmental stages and through distinct cellular mechanisms, including heterochromatin formation. These findings have important implications for how loci that cause postzygotic reproductive isolation are viewed.
{"title":"How can satellite DNA divergence cause reproductive isolation? Let us count the chromosomal ways.","authors":"Patrick M Ferree, Satyaki Prasad","doi":"10.1155/2012/430136","DOIUrl":"https://doi.org/10.1155/2012/430136","url":null,"abstract":"<p><p>Satellites are one of the most enigmatic parts of the eukaryotic genome. These highly repetitive, noncoding sequences make up as much as half or more of the genomic content and are known to play essential roles in chromosome segregation during meiosis and mitosis, yet they evolve rapidly between closely related species. Research over the last several decades has revealed that satellite divergence can serve as a formidable reproductive barrier between sibling species. Here we highlight several key studies on Drosophila and other model organisms demonstrating deleterious effects of satellites and their rapid evolution on the structure and function of chromosomes in interspecies hybrids. These studies demonstrate that satellites can impact chromosomes at a number of different developmental stages and through distinct cellular mechanisms, including heterochromatin formation. These findings have important implications for how loci that cause postzygotic reproductive isolation are viewed.</p>","PeriodicalId":37545,"journal":{"name":"Genetics Research International","volume":"2012 ","pages":"430136"},"PeriodicalIF":0.0,"publicationDate":"2012-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2012/430136","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"30602115","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}
Pub Date : 2012-01-01Epub Date: 2012-03-25DOI: 10.1155/2012/758384
Sebastián Chávez, David S Gross, Damien Hermand, Carlos Suñé
This special issue of Genetics Research International is dedicated to transcription elongation and the role that it plays in the control of gene expression. As K. Brannan and D. Bentley highlight in their retrospective review, 30 years after the first examples of gene control during transcription elongation were described, the importance of this step of the RNA biogenesis process has become increasingly clear, in parallel with myriad findings that connect transcription elongation to almost every relevant genome-related phenomenon. It is, therefore, gratifying to present the most current work from an array of leading scientists, who offer in one rich volume up-to-date review articles of this interesting field. Addressed are the covalent modifications of the C-terminal domain of the largest subunit of RNA polymerase II, whose extensive studies have launched the interesting paradigm of a CTD code governing and integrating cotranscriptionally the different steps of mRNA biogenesis. The teams led by A. Greenleaf (B. Bartkowiak et al.) and A. Ansari (D. Zhang et al.) review this important aspect of RNA-polymerase-II-dependent transcription. They discuss the readers, writers, and erasers of the posttranslational modifications that occur on the CTD and that function as a binding platform for enzymatic complexes that regulate Pol II elongation, pre-mRNA splicing, RNA export from the nucleus, chromatin remodelling, and DNA repair. Also featured is the way transcription is ruled by the other great code, that is, the histone code, a panoply of specific interactions between genome effectors and chromatin that is mediated by covalent modifications of the histones. E. M. Crisucci and K. M. Arndt explore the roles of the Paf1 complex (Paf1C) in regulating gene expression in both budding yeast and metazoans. They review evidence that Paf1C associates with elongating Pol II, and by doing so facilitates histone modifications to the underlying chromatin template as well as contributes to transcription termination and RNA 3′-end formation. A complementary view of chromatin dynamics during transcription elongation is provided by A. A. Duina, who provides a comprehensive review of the roles of the histone chaperones Spt6 and FACT in facilitating passage of Pol II on the chromatin template. He compares and contrasts their mechanisms, highlighting recent evidence indicating that they travel across transcribed regions in likely association with elongating Pol II, where they play an important role in the removal and redeposition of nucleosomes during polymerase elongation. Cotraversal of Pol II and its regulatory factors is also an important aspect of those regulatory phenomena affecting the transition between initiation and elongation and during early elongation. L. A. Stargell and colleagues (M. N. Yearling et al.) describe the complex interplay among the constellation of factors that govern the transition of poised RNA polymerases into active elongation. The po
{"title":"Gene Control during Transcription Elongation.","authors":"Sebastián Chávez, David S Gross, Damien Hermand, Carlos Suñé","doi":"10.1155/2012/758384","DOIUrl":"https://doi.org/10.1155/2012/758384","url":null,"abstract":"This special issue of Genetics Research International is dedicated to transcription elongation and the role that it plays in the control of gene expression. As K. Brannan and D. Bentley highlight in their retrospective review, 30 years after the first examples of gene control during transcription elongation were described, the importance of this step of the RNA biogenesis process has become increasingly clear, in parallel with myriad findings that connect transcription elongation to almost every relevant genome-related phenomenon. It is, therefore, gratifying to present the most current work from an array of leading scientists, who offer in one rich volume up-to-date review articles of this interesting field. \u0000 \u0000Addressed are the covalent modifications of the C-terminal domain of the largest subunit of RNA polymerase II, whose extensive studies have launched the interesting paradigm of a CTD code governing and integrating cotranscriptionally the different steps of mRNA biogenesis. The teams led by A. Greenleaf (B. Bartkowiak et al.) and A. Ansari (D. Zhang et al.) review this important aspect of RNA-polymerase-II-dependent transcription. They discuss the readers, writers, and erasers of the posttranslational modifications that occur on the CTD and that function as a binding platform for enzymatic complexes that regulate Pol II elongation, pre-mRNA splicing, RNA export from the nucleus, chromatin remodelling, and DNA repair. \u0000 \u0000Also featured is the way transcription is ruled by the other great code, that is, the histone code, a panoply of specific interactions between genome effectors and chromatin that is mediated by covalent modifications of the histones. E. M. Crisucci and K. M. Arndt explore the roles of the Paf1 complex (Paf1C) in regulating gene expression in both budding yeast and metazoans. They review evidence that Paf1C associates with elongating Pol II, and by doing so facilitates histone modifications to the underlying chromatin template as well as contributes to transcription termination and RNA 3′-end formation. A complementary view of chromatin dynamics during transcription elongation is provided by A. A. Duina, who provides a comprehensive review of the roles of the histone chaperones Spt6 and FACT in facilitating passage of Pol II on the chromatin template. He compares and contrasts their mechanisms, highlighting recent evidence indicating that they travel across transcribed regions in likely association with elongating Pol II, where they play an important role in the removal and redeposition of nucleosomes during polymerase elongation. Cotraversal of Pol II and its regulatory factors is also an important aspect of those regulatory phenomena affecting the transition between initiation and elongation and during early elongation. L. A. Stargell and colleagues (M. N. Yearling et al.) describe the complex interplay among the constellation of factors that govern the transition of poised RNA polymerases into active elongation. \u0000 \u0000The po","PeriodicalId":37545,"journal":{"name":"Genetics Research International","volume":"2012 ","pages":"758384"},"PeriodicalIF":0.0,"publicationDate":"2012-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2012/758384","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"30602126","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}
Pub Date : 2012-01-01Epub Date: 2011-10-19DOI: 10.1155/2012/795069
Michael B Wells, Györgyi Csankovszki, Laura M Custer
Dosage compensation balances gene expression levels between the sex chromosomes and autosomes and sex-chromosome-linked gene expression levels between the sexes. Different dosage compensation strategies evolved in different lineages, but all involve changes in chromatin. This paper discusses our current understanding of how modifications of the histone H4 tail, particularly changes in levels of H4 lysine 16 acetylation and H4 lysine 20 methylation, can be used in different contexts to either modulate gene expression levels twofold or to completely inhibit transcription.
{"title":"Finding a balance: how diverse dosage compensation strategies modify histone h4 to regulate transcription.","authors":"Michael B Wells, Györgyi Csankovszki, Laura M Custer","doi":"10.1155/2012/795069","DOIUrl":"https://doi.org/10.1155/2012/795069","url":null,"abstract":"<p><p>Dosage compensation balances gene expression levels between the sex chromosomes and autosomes and sex-chromosome-linked gene expression levels between the sexes. Different dosage compensation strategies evolved in different lineages, but all involve changes in chromatin. This paper discusses our current understanding of how modifications of the histone H4 tail, particularly changes in levels of H4 lysine 16 acetylation and H4 lysine 20 methylation, can be used in different contexts to either modulate gene expression levels twofold or to completely inhibit transcription.</p>","PeriodicalId":37545,"journal":{"name":"Genetics Research International","volume":"2012 ","pages":"795069"},"PeriodicalIF":0.0,"publicationDate":"2012-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2012/795069","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"30602129","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}
Pub Date : 2012-01-01Epub Date: 2012-03-06DOI: 10.1155/2012/786930
Pamela Tozzo, Luciana Caenazzo, Daniele Rodriguez
Genetic testing in children raises many important ethical, legal, and social issues. One of the main concerns is the ethically inappropriate genetic testing of minors. Various European countries established professional guidelines which reflect the different countries perspectives regarding the main ethical issues involved. In this paper, we analyze the Italian and the British guidelines by highlighting differences and similarities. We discuss presymptomatic, predictive, and carrier testing because we consider them to be the more ethically problematic types of genetic testing in minors. In our opinion, national guidelines should take into account the different needs in clinical practice. At the same time, in the case of genetic testing the national and supranational protection of minors could be strengthened by approving guidelines based on a common framework of principles and values. We suggest that the Oviedo Convention could represent an example of such a common framework or, at least, it could lead to articulate it.
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