Download or read book A Role for the Let 7 Primary MicroRNA in Target Gene Recognition and Repression written by Robin Deis Trujillo and published by Stanford University. This book was released on 2010 with total page 222 pages. Available in PDF, EPUB and Kindle. Book excerpt: MicroRNA (miRNA) genes produce three noncoding RNA products: the long primary transcript (pri-miRNA), the ~70 nucleotide pre-miRNA, and the ~22-nt mature miRNA. Only the mature miRNA is considered to be the functional species of a miRNA gene in recognizing cognate target mRNAs and modulating their expression. However, mature miRNAs are processed from the primary transcript through sequential endonucleolytic steps. As a result, the mature miRNA sequence is present in all three RNA products of a miRNA gene. It has thus been intrinsically difficult to determine the contribution of each miRNA gene product to target repression. In fact, direct functional roles for pri- and pre-miRNAs have never been ruled out. Here we show that pri- and pre-miRNAs may not be mere transitory intermediates of mature miRNA biogenesis. We found that ectopic expression of the C. elegans miRNA gene let-7 (cel-let-7) in human culture cells results in the production of truncated pre- and mature miRNAs that lack the first two 5' nucleotides, one of which is the first nucleotide of the miRNA seed region (nucleotide SD1). We found this nucleotide to be required for repression of target reporters by cel-let-7 in these cells, demonstrating that pri-let-7 may have a direct role in target repression. Further, we show that the nucleotide sequence and structure of both the pri-/pre-let-7 loop and stem regions play a key role in miRNA gene function in reporter assays. In vitro and in vivo analyses indicated the significance of these regions may be in the mediation of a physical interaction between pri-let-7 and target RNAs. These observations suggest that regulatory information encoded in the structured pri-miRNAs, but absent from mature miRNAs, could be directly interpreted for target recognition and repression through RNA:RNA interaction. Intriguingly, some mutations in the loop nucleotide sequence also restored processing of the 5' ends of C. elegans pre- and mature let-7 in culture cells, demonstrating that the pri-/pre-miRNA loop region can also regulate the precision of mature miRNA biogenesis. Importantly, in the presence of functional pre- and mature let-7, cel-let-7 activity in target repression consists of both SD1-independent and SD1-dependent components, implying potential contributions by both pri- and mature let-7. Finally, we interrogated the effects of pri-/pre-let-7 loop mutations on their ability to rescue a let-7 loss-of-function mutant phenotype in C. elegans. Our results indicate decreased significance of these parameters in the control of worm vulval development, although context-dependent differences in mature miRNA biogenesis between heterologous culture and live animals may partially explain this discrepancy. Taken together the work presented here reveals a novel layer of regulatory complexity encoded in long primary miRNAs that may have broad implications in understanding the mechanisms by which miRNA genes control target expression.
Download or read book A Role for the Let 7 Primary MicroRNA in Target Gene Recognition and Repression written by Robin Deis Trujillo and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: MicroRNA (miRNA) genes produce three noncoding RNA products: the long primary transcript (pri-miRNA), the ~70 nucleotide pre-miRNA, and the ~22-nt mature miRNA. Only the mature miRNA is considered to be the functional species of a miRNA gene in recognizing cognate target mRNAs and modulating their expression. However, mature miRNAs are processed from the primary transcript through sequential endonucleolytic steps. As a result, the mature miRNA sequence is present in all three RNA products of a miRNA gene. It has thus been intrinsically difficult to determine the contribution of each miRNA gene product to target repression. In fact, direct functional roles for pri- and pre-miRNAs have never been ruled out. Here we show that pri- and pre-miRNAs may not be mere transitory intermediates of mature miRNA biogenesis. We found that ectopic expression of the C. elegans miRNA gene let-7 (cel-let-7) in human culture cells results in the production of truncated pre- and mature miRNAs that lack the first two 5' nucleotides, one of which is the first nucleotide of the miRNA seed region (nucleotide SD1). We found this nucleotide to be required for repression of target reporters by cel-let-7 in these cells, demonstrating that pri-let-7 may have a direct role in target repression. Further, we show that the nucleotide sequence and structure of both the pri-/pre-let-7 loop and stem regions play a key role in miRNA gene function in reporter assays. In vitro and in vivo analyses indicated the significance of these regions may be in the mediation of a physical interaction between pri-let-7 and target RNAs. These observations suggest that regulatory information encoded in the structured pri-miRNAs, but absent from mature miRNAs, could be directly interpreted for target recognition and repression through RNA:RNA interaction. Intriguingly, some mutations in the loop nucleotide sequence also restored processing of the 5' ends of C. elegans pre- and mature let-7 in culture cells, demonstrating that the pri-/pre-miRNA loop region can also regulate the precision of mature miRNA biogenesis. Importantly, in the presence of functional pre- and mature let-7, cel-let-7 activity in target repression consists of both SD1-independent and SD1-dependent components, implying potential contributions by both pri- and mature let-7. Finally, we interrogated the effects of pri-/pre-let-7 loop mutations on their ability to rescue a let-7 loss-of-function mutant phenotype in C. elegans. Our results indicate decreased significance of these parameters in the control of worm vulval development, although context-dependent differences in mature miRNA biogenesis between heterologous culture and live animals may partially explain this discrepancy. Taken together the work presented here reveals a novel layer of regulatory complexity encoded in long primary miRNAs that may have broad implications in understanding the mechanisms by which miRNA genes control target expression.
Download or read book Developmental Timing written by and published by Academic Press. This book was released on 2013-09-04 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This new volume of Current Topics in Developmental Biology covers developmental timing, with contributions from an international board of authors. The chapters provide a comprehensive set of reviews covering such topics as the timing of developmental programs in Drosophila, temporal patterning of neural progenitors, and environmental modulation of developmental timing.
Download or read book MicroRNAs in Cancer written by Cesar Lopez-Camarillo and published by CRC Press. This book was released on 2013-02-22 with total page 426 pages. Available in PDF, EPUB and Kindle. Book excerpt: MicroRNA (miRNA) biology is a cutting-edge topic in basic as well as biomedical research. This is a specialized book focusing on the current understanding of the role of miRNAs in the development, progression, invasion, and metastasis of diverse types of cancer. It also reviews their potential for applications in cancer diagnosis, prognosis, and th
Download or read book Plant MicroRNAs written by Stefan de Folter and published by Humana Press. This book was released on 2019-01-31 with total page 363 pages. Available in PDF, EPUB and Kindle. Book excerpt: This detailed volume provides a collection of protocols for the study of miRNA functions in plants. Beginning with coverage of miRNA function, biogenesis, activity, and evolution in plants, the book continues by guiding readers through methods on the identification and detection of plant miRNAs, bioinformatic analyses, and strategies for functional analyses of miRNAs. Written in the highly successful Methods in Molecular Biology series format, chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and tips on troubleshooting and avoiding known pitfalls. Authoritative and cutting-edge, Plant MicroRNAs: Method and Protocols aims to ensure successful results in the further study of this vital area of plant science.
Download or read book Tumor Microenvironment and Cellular Stress written by Constantinos Koumenis and published by Springer Science & Business Media. This book was released on 2013-11-23 with total page 293 pages. Available in PDF, EPUB and Kindle. Book excerpt: The collection of chapters in this proceeding volume reflects the latest research presented at the Aegean meeting on Tumor Microenvironment and Cellular Stress held in Crete in Fall of 2012. The book provides critical insight to how the tumor microenvironment affects tumor metabolism, cell stemness, cell viability, genomic instability and more. Additional topics include identifying common pathways that are potential candidates for therapeutic intervention, which will stimulate collaboration between groups that are more focused on elucidation of biochemical aspects of stress biology and groups that study the pathophysiological aspects of stress pathways or engaged in drug discovery.
Download or read book MicroRNAs written by Krishnarao Appasani and published by Cambridge University Press. This book was released on 2009-08-20 with total page 580 pages. Available in PDF, EPUB and Kindle. Book excerpt: MicroRNAs (miRNAs) are RNA molecules, conserved by evolution, that regulate gene expressions and their recent discovery is revolutionising both basic biomedical research and drug discovery. Expression levels of MiRNAs have been found to vary between tissues and with developmental stages and hence evaluation of the global expression of miRNAs potentially provides opportunities to identify regulatory points for many different biological processes. This wide-ranging reference work, written by leading experts from both academia and industry, will be an invaluable resource for all those wishing to use miRNA techniques in their own research, from graduate students, post-docs and researchers in academia to those working in R&D in biotechnology and pharmaceutical companies who need to understand this emerging technology. From the discovery of miRNAs and their functions to their detection and role in disease biology, this volume uniquely integrates the basic science with industry application towards drug validation, diagnostic and therapeutic development. Forewords by: Sidney Altman, Yale University, Winner of the Nobel Prize in Chemistry, 1989 and Victor R. Ambros, Dartmouth Medical School, Co-discoverer of MicroRNAs
Download or read book Circulating MicroRNAs written by Takahiro Ochiya and published by Humana Press. This book was released on 2013-05-30 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: microRNAs (miRNAs) are small non-coding RNAs that regulate various biological phenomena, such as development and homeostasis. The dysregulation of miRNA leads to disease progression, particularly of cancer. In Circulating MicroRNAs: Methods and Protocols, expert researchers in the field detail recent advances in the isolation, purification and analysis of circulating miRNAs from a variety of sources for research. The book is divided into three main topics. The first section involves the study of secretory miRNAs in cell-cell communication, and the second, the study of circulating miRNAs in body fluids. The last describes the novel techniques used to study circulating miRNAs. Written in the highly successful Methods in Molecular BiologyTM series format, chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and key tips on troubleshooting and avoiding known pitfalls. Authoritative and practical, Circulating MicroRNAs: Methods and Protocols seeks to aid scientists in dealing with the recent advances of RNAi technology from the bench to the bedside.
Download or read book Plant Physiological Aspects of Phenolic Compounds written by Marcos Soto-Hernández and published by BoD – Books on Demand. This book was released on 2019-09-04 with total page 122 pages. Available in PDF, EPUB and Kindle. Book excerpt: Phenolic compounds are considered secondary metabolites within the physiology of a plant. They have different functions, such as pollination systems, sun protection, protection against pathogens and diseases, etc.Research on these compounds has increased due to the number of molecules they can include and the different biological activities they demonstrate. It is important to know the methods of extracting molecules, the biosynthesis routes, and their relationship with activities that can benefit from their consumption. Therefore, the book includes chapters that provide information on extraction and optimization techniques, biosynthetic pathways, and the identification and characterization of miRNAs involved in the regulation of their biosynthesis.
Download or read book Handbook on Immunosenescence written by Tamas Fulop and published by Springer Science & Business Media. This book was released on 2009-02-27 with total page 1693 pages. Available in PDF, EPUB and Kindle. Book excerpt: This authoritative handbook covers all aspects of immunosenescence, with contributions from experts in the research and clinical areas. It examines methods and models for studying immunosenescence; genetics; mechanisms including receptors and signal transduction; clinical relevance in disease states including infections, autoimmunity, cancer, metabolic syndrome, neurodegenerative diseases, frailty and osteoporosis; and much more.
Download or read book The Liver written by Irwin M. Arias and published by John Wiley & Sons. This book was released on 2020-03-09 with total page 1156 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bridging the gap between basic scientific advances and the understanding of liver disease — the extensively revised new edition of the premier text in the field. The latest edition of The Liver: Biology and Pathobiology remains a definitive volume in the field of hepatology, relating advances in biomedical sciences and engineering to understanding of liver structure, function, and disease pathology and treatment. Contributions from leading researchers examine the cell biology of the liver, the pathobiology of liver disease, the liver’s growth, regeneration, metabolic functions, and more. Now in its sixth edition, this classic text has been exhaustively revised to reflect new discoveries in biology and their influence on diagnosing, managing, and preventing liver disease. Seventy new chapters — including substantial original sections on liver cancer and groundbreaking advances that will have significant impact on hepatology — provide comprehensive, fully up-to-date coverage of both the current state and future direction of hepatology. Topics include liver RNA structure and function, gene editing, single-cell and single-molecule genomic analyses, the molecular biology of hepatitis, drug interactions and engineered drug design, and liver disease mechanisms and therapies. Edited by globally-recognized experts in the field, this authoritative volume: Relates molecular physiology to understanding disease pathology and treatment Links the science and pathology of the liver to practical clinical applications Features 16 new “Horizons” chapters that explore new and emerging science and technology Includes plentiful full-color illustrations and figures The Liver: Biology and Pathobiology, Sixth Edition is an indispensable resource for practicing and trainee hepatologists, gastroenterologists, hepatobiliary and liver transplant surgeons, and researchers and scientists in areas including hepatology, cell and molecular biology, virology, and drug metabolism.
Download or read book Handbook of Nutrition Diet and Epigenetics written by Vinood B. Patel and published by Springer. This book was released on 2019-02-27 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This multivolume reference work addresses the fact that the well being of humankind is predicated not only on individuals receiving adequate nutrition but also on their genetic makeup. The work includes more than 100 chapters organized in the following major sections: Introduction and Overview; Epigenetics of Organs and Diseases in Relation to Diet and Nutrition; Detailed Processes in Epigenetics of Diet and Nutrition; Modulating Epigenetics with Diet and Nutrition; and Practical Techniques. While it is well known that genes may encode proteins responsible for structural and dynamic components, there is an increasing body of evidence to suggest that nutrition itself may alter the way in which genes are expressed via the process of epigenetics. This is where chemically imposed alteration in the DNA sequence occurs or where the functional expression of DNA is modulated. This may include changes in DNA methylation, non-coding RNA, chromatin, histone acetylation or methylation, and genomic imprinting. Knowledge regarding the number of dietary components that impact on epigenetic processes is increasing almost daily. Marshalling all the information on the complex relationships between diet, nutrition, and epigenetic processes is somewhat difficult due to the wide myriad of material. It is for this reason that the present work has been compiled.
Download or read book Handbook of Computational Molecular Biology written by Srinivas Aluru and published by CRC Press. This book was released on 2005-12-21 with total page 1108 pages. Available in PDF, EPUB and Kindle. Book excerpt: The enormous complexity of biological systems at the molecular level must be answered with powerful computational methods. Computational biology is a young field, but has seen rapid growth and advancement over the past few decades. Surveying the progress made in this multidisciplinary field, the Handbook of Computational Molecular Biology of
Download or read book MiRNomics written by Malik Yousef and published by . This book was released on 2014 with total page 333 pages. Available in PDF, EPUB and Kindle. Book excerpt: In miRNomics: MicroRNA Biology and Computational Analysis, expert researchers in the field present an overview of the current state of the art and aim to put the respective areas of research into a larger perspective. These include methods and techniques ranging from miRNA biogenesis, their biological function, computational analyses to their medical implications and applications. Written in the highly successful Methods in Molecular Biology series format, chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and key tips on troubleshooting and avoiding known pitfalls. Authoritative and practical, miRNomics: MicroRNA Biology and Computational Analysis seeks to aid scientists in the further study into miRNA research and statistics.
Download or read book Regulation of microRNAs written by Helge Großhans and published by Springer. This book was released on 2011-08-25 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt: Given this pervasiveness and importance of miRNA-mediated gene regulation, it should come as little surprise that miRNAs themselves are also highly regulated. However, the recent explosion of knowledge on this topic has been remarkable, providing a primary motivation for publication of this book. As miRNAs are transcribed by RNA polymerase II, the enzyme that also generates mRNAs, it was perhaps not unexpected that miRNA transcription would be subject to regulation, and we have willfully mitted this aspect from this monograph. However, what has been unexpected is the extent of post-transcriptional regulation of miRNAs that is illustrated in this book.
Download or read book Hormones Metabolism and the Benefits of Exercise written by Bruce Spiegelman and published by Springer. This book was released on 2018-03-07 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt: The world is faced with an epidemic of metabolic diseases such as obesity and type 2 diabetes. This is due to changes in dietary habits and the decrease in physical activity. Exercise is usually part of the prescription, the first line of defense, to prevent or treat metabolic disorders. However, we are still learning how and why exercise provides metabolic benefits in human health. This open access volume focuses on the cellular and molecular pathways that link exercise, muscle biology, hormones and metabolism. This will include novel “myokines” that might act as new therapeutic agents in the future.
Download or read book Cell Cycle Regulation written by Philipp Kaldis and published by Results and Problems in Cell Differentiation. This book was released on 2006-06-26 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a state-of-the-art summary of the latest achievements in cell cycle control research with an outlook on the effect of these findings on cancer research. The chapters are written by internationally leading experts in the field. They provide an updated view on how the cell cycle is regulated in vivo, and about the involvement of cell cycle regulators in cancer.
