Showing papers in "Annual Review of Genetics in 1989"
TL;DR: The history and present situation of Spanish language, culture, literature, cuisine, tourism, and more are explored in more detail in this booklet.
Abstract: TELOMERES DEFINED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 579 TELOMERE FUNCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 580 SEQUENCE AND STRUCTURE OF TELOMERES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 581 SOLUTIONS FOR REPLICATION OF DNA TERMINI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 586 STRUCTURE OF SUBTELOMERIC REGIONS.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 589 FORMA TION OF TELOMERES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ... . . . . . .. 591 PROTEINS THAT INTERACT WITH TELOMERES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 594 ARE TELOMERES REALLY ESSENTIAL? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 597 FUTURE PROSPECTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 598
1,923Â citations
TL;DR: This review indicates that few experiments approach basic issues such as the number of loci that contribute to within-population variation, the rate of polygenic mutation, the extent of pleiotropy, the mechanisms that maintain additive variance, and the reasons for reduced fitness of extreme phenotypes.
Abstract: Our emphasis is on the genetic basis of quantitative variation, and its effects on the evolution of quantitative. Our review indicates that few experiments approach basic issues such as the number of loci that contribute to within-population variation, the rate of polygenic mutation, the extent of pleiotropy, the mechanisms that maintain additive variance, and the reasons for reduced fitness of extreme phenotypes
665Â citations
TL;DR: In this review, the discussion of mechanisms attempts to be exhaustive, drawing not only upon direct experimental investigations of alternatively spliced genes, but also upon relevant themes derived from the study of constitutive splicing.
Abstract: In this review, we focus upon the mechanistic, functional, and evolutionary aspects of alternative splicing. The discussion of mechanisms attempts to be exhaustive, drawing not only upon direct experimental investigations of alternatively spliced genes, but also upon relevant themes derived from the study of constitutive splicing
641Â citations
TL;DR: The theoretical and empirical studies reviewed here yield the conclusion that Drosophila TEs are maintained in populations as a result of transpositional increase in copy number, and that their spread is checked by one or more opposing forces.
Abstract: The theoretical and empirical studies reviewed here yield the conclusion that Drosophila TEs are maintained in populations as a result of transpositional increase in copy number, and that their spread is checked by one or more opposing forces. In other words, the concept that TEs are essentially intragenomic parasites is supported
440Â citations
TL;DR: It is an especially encouraging result that proteins appear to tolerate most substitutions, even those that are destabilizing, without significant changes in the native structure.
Abstract: There is tremendous variability in the importance of individual amino acids in protein sequences. On the one hand, nonconservative residue substitutions can be tolerated with no loss of activity at many residue positions, especially those exposed on the protein surface. On the other hand, destabilizing mutations can occur at a large number of different sites in a protein, and for many proteins such mutations account for more than half of the randomly isolated missense mutations that confer a defective phenotype. At sites that are key determinants of stability or activity, even residue substitutions that are generally considered to be conservative (e.g., Glu in equilibrium Asp, Asn in equilibrium Asp, Ile in equilibrium Leu, Lys in equilibrium Arg and Ala in equilibrium Gly) can have severe phenotypic effects. Unfortunately, this means that there is no simple way to infer the likely effect of an amino acid substitution on the basis of sequence information alone. A nonconservative Gly----Arg substitution could be phenotypically silent at one position while a conservative Asn----Asp change could lead to complete loss of activity at another position. For proteins whose structures are known, it is often possible to predict whether particular residue substitutions will be destabilizing, as long as detailed estimates of the destabilization energy are not required. Substitutions that introduce polar groups, large cavities, or overly large side chains into the hydrophobic core are potentially the most destabilizing. Substitutions that disrupt hydrogen bonding or electrostatic interactions can also have significant effects, although the destabilization caused by these substitutions is smaller than that caused by severe core mutations. Destabilizing substitutions that involve replacing glycines in turns, or introducing prolines into alpha-helices and other disallowed positions are also reasonably common. Finally, most solvent exposed residues can apparently be freely substituted without serious effects on protein stability. Although exceptions may occur, these generalizations serve to summarize a large body of information and can be rationalized in physical and chemical terms. It is an especially encouraging result that proteins appear to tolerate most substitutions, even those that are destabilizing, without significant changes in the native structure. For proteins whose structures are known, this means that it is reasonable to interpret mutant phenotypes in terms of the wild-type structure. For proteins whose structures are not known, it is reasonable to infer that mutations that reduce activity without affecting stability are directly involved in function.(ABSTRACT TRUNCATED AT 400 WORDS)
437Â citations
TL;DR: The investigations reviewed here indicate that the eukaryotic genome is an integrated structural, functional, and evolutionary system.
Abstract: The investigations reviewed here indicate that the eukaryotic genome is an integrated structural, functional, and evolutionary system. This view arose from a comparative study of vertebrate genomes, centered on the analysis of their compositional patterms, namely of the compositional distributions of large DNA fragments, coding sequences, and introns
367Â citations
TL;DR: This article reviews the processes that work together to achieve stable maintenance in plasmid life cycles and attempts to explain how they work together.
Abstract: A closer analysis of different plasmids revealed that some of the stability functions did not involve real partition functions, i.e. functions that actively distribute the plasmid molecules to the daughter cells, but affected other aspects of plasmid life cycles, such as the resolution of oligomers formed by recombination or the killing of plasmid-free cells by plasmid-coded functions. This article reviews these processes and attempts to explain how they work together to achieve stable maintenance
315Â citations
TL;DR: Evidence implicating a wide-range of neurophysiological and biochemical traits as potential candidates for the major loci imparting increased risk for alcoholism is examined.
Abstract: In this review, we develop and document the emergence of the current view of the genetics of alcoholism We also examine evidence implicating a wide-range of neurophysiological and biochemical traits as potential candidates for the major loci imparting increased risk for alcoholism Finally, we touch briefly upon the methods and strategies being employed in the search for those loci
313Â citations
TL;DR: The Regu la tors, the Regu latory Pairs, and the E nvZIOmpR System are described.
Abstract: INTRODUCTION . . . .... . . .... . . . . HOMOLOGY BETWEEN SIGNAL TRANSDUCING REGULATORY PAIRS . . . . . .. . . Th e S enso rs . . . . . . . . . . . . . . . . . . . . .. . . . . . . . .... . .. . . . . . . .. .. . . . . . ...... . . . . . .. .. . . . . . . . ...... . . . . . . . . The Regu la tors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Identification of Ne w Signa l Tra nsdu cing Regu latory Pairs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CONSERVED INTERACTION BETWEEN SENSOR AND REGULATOR . . . . . . . . . .. . . Th e NtrBINtrC System . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . The CheA IChe Y + Che B S ystem . . . . . . . . . . . . . . . .. . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . The E nvZIOmpR System . . . . . . . . . . . . . . . . . . . . . . . . . .. . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Th e PhoR IPhoB S ystem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C ross-Ta lk . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FUNCTION OF THE SENSOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Signa l De te c tion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Domain Structure of th e S enso rs .. . . . . .. . .. .. .. . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . FUNCTION OF THE REGULATOR . . . ..... . . . . . . . . . . . . . . . . . . . . . . . .. . NtrC Sub cla ss . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . OmpR Subcla ss . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CheB Subcla ss . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Che Y Subcla ss . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . GENETIC ANALYSIS OF SIGNAL TRANSDUCTION IN REGULATORY PAIRS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . .. . . SUMMARY AND PROSPECTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ... .. .. . . . . . . . . . . . . ... .
305Â citations
TL;DR: This review focuses on three approaches used to study recombination mediated by cellular functions: extrachromosomal recombination between transfected DNA molecules; chromosomal recombinating between repeated genes stably incorporated in the genome; and targeted recombinationbetween introduced DNA molecules and homologous sequences in the chromosome.
Abstract: This review focuses on three approaches used to study recombination mediated by cellular functions: (a) extrachromosomal recombination between transfected DNA molecules; (b) chromosomal recombination between repeated genes stably incorporated in the genome; and (c) targeted recombination between introduced DNA molecules and homologous sequences in the chromosome
248Â citations
TL;DR: This review focuses on the mechanism underlying the promiscuous transactivation activity of the E1A protein.
Abstract: The generality with which the E1A protein can act is further emphasized by its ability to stimulate transcription by RNA polymerase III. Such observations have led to the seemingly inevitable conclusion that the E1A proteins act by a mechanism that must be both indirect and general. In this review we focus on the mechanism underlying the promiscuous transactivation activity of the E1A protein
TL;DR: This review summarizes the current knowledge of this particular role of proteases responsible for the initial cleavages in most of these interesting degradative processes.
Abstract: Over the last ten years it has become increasingly apparent that turnover of particular proteins, under specific conditions, can play as central a role as the transcriptional and translational regulatory mechanisms. This review summarizes our current knowledge of this particular role of proteases responsible for the initial cleavages in most of these interesting degradative processes
TL;DR: Based on the model of DNA looping and other new developments in E. coli, the reformulation of how regulatory proteins and DNA sites interact with each other and thereby govern gene expression is discussed.
Abstract: Based on the model of DNA looping and other new developments in E. coli, we discuss here the reformulation of how regulatory proteins and DNA sites interact with each other and thereby govern gene expression. We describe a few examples of control systems of E. coli, mosthy negative control, which involve distant and multipartite sites
TL;DR: Of the ten transposable element systems that have been genetically identified in maize, two have contributed most of the molecular data and are used as the principle examples to outline the current status in the molecular analysis of transposition.
Abstract: Of the ten transposable element systems that have been genetically identified in maize (listed in 55), two have contributed most of the molecular data. These are the Enhancer (En) or Suppressor-mutator (Spm) system and the Activator (Ac) system. With a certain preference for En/Spm, these two systems are used as the principle examples to outline the current status in the molecular analysis of transposition
TL;DR: Current understanding of both the mechanism and regulation of these DNA rearrangement events are described.
Abstract: Both variable region gene assembly and HC class switching seem to be regulated processes. The mechanisms that control these events appear to be intimately related to the progression of B-lymphocyte differentiation. In this review we describe current understanding of both the mechanism and regulation of these DNA rearrangement events
TL;DR: This review limits this review to several systems that illustrate common molecular themes in control of virulence properties rather than presenting a comprehensive review of this extensive literature.
Abstract: In this review, we concentrate on genetic control of bacterial virulence. We limit this review to several systems that illustrate common molecular themes in control of virulence properties rather than presenting a comprehensive review of this extensive literature
TL;DR: The evidence that habituation results from reversible modifications in cell heredity, known as epigenetic changes, is summarized and possible mechanisms for these changes are discussed.
Abstract: The aim of this contribution is to review the basic features of habituation for auxin and cytokinin. I summarize the evidence that habituation results from reversible modifications in cell heredity, known as epigenetic changes, and discuss possible mechanisms for these changes
TL;DR: The cellular and genetic basis of pollen recognition in Brassica is reviewed in light of recent data derived from the molecular genetic analysis of the interaction between pollen and stigma.
Abstract: After a brief description of the distribution and diversity of SI systems, we detail the SI system that operates in the crucifer family, the Brassicaceae, (which includes such plants as broccoli, cabbage, kale, mustards, oil seed crops and radish). Specifically, the cellular and genetic basis of pollen recognition in Brassica is reviewed in light of recent data derived from the molecular genetic analysis of the interaction between pollen and stigma
TL;DR: This review explores whether the systems controlling rDNA copy number in flies represent mechanisms unique to rDNA.
Abstract: Throughout this review we are guided by several basic questions. First, to what extent do recombinational processes act to control rDNA copy number in wild-type Drosophila? Second, if any of these processes is induced by an rDNA deficiency and therefore can be considered as a compensatory mechanism, then by what mechanism(s) is an rDNA deficiency sensed and then corrected? Third, we explore whether the systems controlling rDNA copy number in flies represent mechanisms unique to rDNA
TL;DR: In this article, the authors focus on the population aspects of genetic variation, i.e. the variation and evolution of genetic structure within and between species, by identifying probable cases of gene loci under selection.
Abstract: The present review is focussed on the population aspects of genetic variation, i.e. the variation and evolution of genetic structure within and between species. Population survey data, by identifying probable cases of gene loci under selection, provide information for planning biochemical and physiological studies of adaptation on one hand, and molecular population genetic studies of gene structure on the other
TL;DR: Traditional genetic analyses of C. elegans have been extended with a powerful array of new reagents and methodologies that make an integrated approach to muscle biology possible in this organism.
Abstract: Within the past several years, traditional genetic analyses of C. elegans have been extended with a powerful array of new reagents and methodologies thatmake an integrated approach to muscle biology possible in this organism. Mutations can now be related to their genes and proteins; proteins and genes can be related to the corresponding mutants; and many of these components can be manipulated by design in vivo
TL;DR: The organization of this chromosome is defined by examining repeated sequences on the short arm of the chromosome, genes on the long arm, a genetic linkage map of the chromosomes and future gene mapping studies.
Abstract: In particular, we define the organization of this chromosome by examining: repeated sequences on the short arm of the chromosome, genes on the long arm, a genetic linkage map of the chromosome and future gene mapping studies (long-range restriction fragments, sequencing, and isolation of genes expressed in different fetal tissues)