Transfer RNAs (tRNAs) are one of the classical non-coding RNAs whose lengths are approximately 70–100 bases. The secondary structure of tRNAs can be represented as the cloverleaf with 4 stems, and the three dimensional structure as an “L” shape. Historically, the basic function of tRNA as an essential component of translation was established in 1960s, i.e., each tRNA is charged with a target amino acid and these are delivered to the ribosome during protein synthesis. However, recent data suggests that the role of tRNA in cellular regulation goes beyond this paradigm. In most Archaea and Eukarya, precursor tRNAs are often interrupted by a short intron inserted strictly between the first and second nucleotide downstream of the anticodon, known as canonical nucleotide position (37/38). Recently, a number of reports describe novel aspects of tRNAs in terms of gene diversity, for example, several types of disrupted tRNA genes have been reported in the Archaea and primitive Eukarya, including multiple-intron-containing tRNA genes, split tRNA genes, and permuted tRNA genes. Our understanding of the enzymes involved in tRNA functions (e.g., aminoacyl-tRNA synthetase, tRNA splicing endonuclease, tRNA ligase) has deepened. Moreover, it is well known that tRNA possesses many types of base modifications whose enzymatic regulations remain to be fully elucidated. It was reported that impaired tRNA nuclear-cytoplasmic export links DNA damage and cell-cycle checkpoint. Furthermore, a variety of additional functions of tRNA, beyond its translation of the genetic code, have emerged rapidly. For instance, tRNA cleavage is a conserved part of the responses to a variety of stresses in eukaryotic cells. Age-associated or tissue-specific tRNA fragmentation has also been observed. Several papers suggested that some of these tRNA fragments might be involve in the cellular RNA interference (RNAi) system. These exciting data, have lead to this call for a Research Topic, that plans to revisit and summarize the molecular biology of tRNA. Beyond the topics outlined above, we have highlighted recent developments in bioinformatics tools and databases for tRNA analyses.

With a Foreword by Sydney Brenner (Nobel laureate in Physiology or Medicine, 2002)This biography details the life of Paul Berg (Emeritus Professor at Stanford University), tracing Berg's life from birth, in 1926, to the present, with special emphasis on his enormous scientific contributions, including being the first to develop technology that led to gene cloning science. In 1980, Berg received a Nobel Prize in chemistry for this work.In addition to his contributions in the research laboratory, Berg orchestrated and oversaw a historic meeting at Asilomar, California that centered on a threatening controversy surrounding the perception by some of the harmful potential of recombinant DNA technology. This meeting did much to forestall this controversy and to put in place the regulation of recombinant DNA work, thus putting fears to rest.The recombinant DNA controversy was a historic outcome of the discovery of gene cloning. Notably, it represented a paramount example of scientific foresight and due diligence by the scientific community, rather than by regulatory entities in the United States and many other countries. The ultimate acceptance of gene/DNA cloning led to a new era of modern biology that thrives to the present.This book is aimed primarily at scientists and those in training. The book strives to simply provide information for the general reader, but is not specifically tailored for a general reading audience.While many books cover the recombinant DNA controversy, none have satisfactorily addressed this historic period and are often contradictory about the many who's, where's, and why's involved. Additionally, the great majority of these were written by non-scientists. This biography of Paul Berg provides access to numerous archived letters and documents at Stanford University not previously addressed, and to the chronology of events as recalled and documented by him, as well as other key personalities, many of whom were interviewed.

The literature on recoding is scattered, so this superb book ?lls a need by prov- ing up-to-date, comprehensive, authoritative reviews of the many kinds of recoding phenomena. Between 1961 and 1966 my colleagues and I deciphered the genetic code in Escherichia coli and showed that the genetic code is the same in E. coli, Xenopus laevis, and guinea pig tissues. These results showed that the code has been c- served during evolution and strongly suggested that the code appeared very early during biological evolution, that all forms of life on earth descended from a c- mon ancestor, and thus that all forms of life on this planet are related to one another. The problem of biological time was solved by encoding information in DNA and retrieving the information for each new generation, for it is easier to make a new organism than it is to repair an aging, malfunctioning one. Subsequently, small modi?cations of the standard genetic code were found in certain organisms and in mitochondria. Mitochondrial DNA only encodes about 10–13 proteins, so some modi?cations of the genetic code are tolerated that pr- ably would be lethal if applied to the thousands of kinds of proteins encoded by genomic DNA.

By virtue of their role as catalysts of the aminoacylation reaction, the aminoacyl-tRNA synthetases ensure that the first step of translation is performed quickly and accurately. In this volume of 36 separate chapters, the many facets of this ancient and ubiquitous family are reviewed, including their surprising structural diversity, enzymology, tRNA interaction properties, and curious alternative functions. These chapters illustrate the degree to which the aminoacyl-tRNA synthetases employ a variety of mechanisms to carry out both the standard functions related to the synthesis of aminoacylated tRNA for protein synthesis, as well as the surprising functions associated with amino acid biosynthesis, cytokine function, and even the processivity of DNA replication. Other chapters explore the regulation of their synthesis, their role in disease, and their prospects as targets for antibacterial therapeutics. This monograph will be a valuable resource for all scientists interested in the fundamentals of protein synthesis from both a basic research and clinical perspective, as well as the relation of translational components to the evolution of the genetic code.

The study of evolution at the molecular level has given the subject of evolutionary biology a new significance. Phylogenetic 'trees' of gene sequences are a powerful tool for recovering evolutionary relationships among species, and can be used to answer a broad range of evolutionary and ecological questions. They are also beginning to permeate the medical sciences. In this book, the authors approach the study of molecular evolution with the phylogenetic tree as a central metaphor. This will equip students and professionals with the ability to see both the evolutionary relevance of molecular data, and the significance evolutionary theory has for molecular studies. The book is accessible yet sufficiently detailed and explicit so that the student can learn the mechanics of the procedures discussed. The book is intended for senior undergraduate and graduate students taking courses in molecular evolution/phylogenetic reconstruction. It will also be a useful supplement for students taking wider courses in evolution, as well as a valuable resource for professionals. First student textbook of phylogenetic reconstruction which uses the tree as a central metaphor of evolution. Chapter summaries and annotated suggestions for further reading. Worked examples facilitate understanding of some of the more complex issues. Emphasis on clarity and accessibility.

The genetic code was deciphered experimentally around 1966 and for a number of years scientists considered it to be "universal" for all forms of life. In 1981 researchers shocked the scientific community with the discovery that the code differed in mitochondria and certain other organisms, evidence that the genetic code was still evolving. This book discusses the distribution and origin of the non-universal codes and examines the possible mechanisms of code changes, making it essential reading for all those interested in evolutionary genetics.

No longer simple line drawings on a page, molecular structures can now be viewed in full-figured glory, often in color and even with interactive possibilities. Anatomy of Gene Regulation is the first book to present the parts and processes of gene regulation at the three-dimensional level. Vivid structures of nucleic acids and their companion proteins are revealed in full-color, three-dimensional form. Beginning with a general introduction to three-dimensional structures, the book looks at the organization of the genome, the structure of DNA, DNA replication and transcription, splicing, protein synthesis, and ultimate protein death. Throughout, the text employs a discussion of genetics and structural mechanics. The concise and unique synthesis of information will offer insight into gene regulation, and into the development of methods to interfere with regulation at diseased states. This textbook and its accompanying web site are appropriate for both undergraduate and graduate students in genetics, molecular biology, structural biology, and biochemistry courses.

This laboratory guide represents a growing collection of tried, tested and optimized laboratory protocols for the isolation and characterization of eukaryotic RNA, with lesser emphasis on the characterization of prokaryotic transcripts. Collectively the chapters work together to embellish the RNA story, each presenting clear take-home lessons, liberally incorporating flow charts, tables and graphs to facilitate learning and assist in the planning and implementation phases of a project.RNA Methodologies, 3rd edition includes approximately 30% new material, including chapters on the more recent technologies of RNA interference including: RNAi; Microarrays; Bioinformatics. It also includes new sections on: new and improved RT-PCR techniques; innovative 5' and 3' RACE techniques; subtractive PCR methods; methods for improving cDNA synthesis.* Author is a well-recognized expert in the field of RNA experimentation and founded Exon-Intron, a well-known biotechnology educational workshop center * Includes classic and contemporary techniques * Incorporates flow charts, tables, and graphs to facilitate learning and assist in the planning phases of projects