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1. |
γ‐Tubulin: The hub of cellular microtubule assemblies |
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BioEssays,
Volume 15,
Issue 10,
1993,
Page 637-643
Harish C. Joshi,
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摘要:
AbstractIn eukaryotic cells a specialized organelle called the microtubule organizing center (MTOC) is responsible for disposition of microtubules in a radial, polarized array in interphase cells and in the spindle in mitotic cells. Eukaryotic cells across different species, and different cell types within single species, have morphologically diverse MTOCs, but these share a common function of organizing microtubule arrays. MTOCs effect microtubule organization by initiating microtubule assembly and anchoring microtubules by their slowly growing minus ends, thus ensuring that the rapidly growing plus ends extend distally in each microtubule array. The goal is to define molecular components of the MTOC responsible for regulating microtubule assembly. One approach to defining the molecules responsible for MTOC function is to look for molecules common to all MTOCs. A newly discovered centrosomal protein, γ‐tubulin, is found in MTOCs in cells from many different organisms, and has several properties which make it a candidate for both initiation of microtubule assembly and anchorage. The hypothesis that γ‐tubulin plays a role in MTOCs in microtubule initiation and anchorage is currently being tested by a variety of experimental appro
ISSN:0265-9247
DOI:10.1002/bies.950151002
出版商:Wiley Subscription Services, Inc., A Wiley Company
年代:1993
数据来源: WILEY
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2. |
The molecular biology of taste transduction |
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BioEssays,
Volume 15,
Issue 10,
1993,
Page 645-650
Robert F. Margolskee,
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摘要:
AbstractTaste cells respond to a wide variety of chemical stimuli: certain ions are perceived as salty (Na+) or sour (H+); other small molecules are perceived as sweet (sugars) and bitter (alkaloids). Taste has evolutionary value allowing animals to respond positively (to sweet carhohydrates and salty NaCl) or aversively (to bitter poisons and corrosive acids). Recently, some of the proteins involved in taste transduction have been cloned. Several different G proteins have been identified and cloned from taste tissue: gustducin is a taste cell specific G protein closely related to the transducins. Work is under way to clone additional components of the taste transduction pathways. The combination of electrophysiology, biochemistry and molecular biology is being used to characterize taste receptor cells and their sensory transduction mechanisms.
ISSN:0265-9247
DOI:10.1002/bies.950151003
出版商:Wiley Subscription Services, Inc., A Wiley Company
年代:1993
数据来源: WILEY
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3. |
Localized RNAs and their functions |
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BioEssays,
Volume 15,
Issue 10,
1993,
Page 651-658
Dali Ding,
Howard D. Lipshitz,
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摘要:
AbstractThe eukaryotic cell is partitioned by membranes into spatially and functionally discrete subcellular organelles. In addition, the cytoplasm itself is partitioned into discrete subregions that carry out specific functions. Such compartmentation can be achieved by localizing proteins and RNAs to different subcellular regions. This review will focus on localized RNAs, with a particular emphasis on RNA localization mechanisms and on the possible biological functions of localization of these RNAs. In recent years, an increasing number of localized RNAs have been identified in a variety of cell types among many animal species. Emphasis here will be on localized RNAs in the most intensively studied systems –DrosophilaandXenopuseggs and early embryo
ISSN:0265-9247
DOI:10.1002/bies.950151004
出版商:Wiley Subscription Services, Inc., A Wiley Company
年代:1993
数据来源: WILEY
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4. |
Common mechanisms for the control of eukaryotic transcriptional elongation |
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BioEssays,
Volume 15,
Issue 10,
1993,
Page 659-665
Anton Krumm,
Tea Meulia,
Mark Groudine,
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摘要:
AbstractRegulation of transcriptional elongation is emerging as an important control mechanism for eukaryotic gene expression. In this essay, we review the basis of the current view of the regulation of elongation in the human c‐mycgene and discuss similarities in elongation control among the c‐myc, Drosophilahsp70and the HIV‐1 genes. Based upon these similarities, we propose a model for control of expression of these genes at the elongation phase of transcription. This model suggests that distinct promoter elements direct the assembly of RNA polymerase II transcription complexes which differ in their elongation effic
ISSN:0265-9247
DOI:10.1002/bies.950151005
出版商:Wiley Subscription Services, Inc., A Wiley Company
年代:1993
数据来源: WILEY
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5. |
Protein splicing: Excision of intervening sequences at the protein level |
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BioEssays,
Volume 15,
Issue 10,
1993,
Page 667-674
Antony A. Cooper,
To M. H. Stevens,
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摘要:
AbstractProtein splicing is an extraordinary post‐translational reaction that removes an intact central “spacer” domain (Sp) from precursor proteins (N‐Sp‐C) while splicing together the N‐ and C‐domains of the precursor, via a peptide bond, to produce a new protein (N‐C). All of the available data on protein splicing fit a model in which these intervening sequences excise at the protein level via a self‐splicing mechanism. Several proteins have recently been discovered that undergo protein splicing, and in two such cases, the excised spacer protein is an endonuclease. Such endonucleases are capable of conferring genetic mobility upon the intervening sequences that encodes them. These intervening sequences define a new family of mobile genetic elements that are translated yet remain phenotypically silent by excising at the protein rather t
ISSN:0265-9247
DOI:10.1002/bies.950151006
出版商:Wiley Subscription Services, Inc., A Wiley Company
年代:1993
数据来源: WILEY
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6. |
The aminoacyl‐tRNA synthetase family: Modules at work |
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BioEssays,
Volume 15,
Issue 10,
1993,
Page 675-687
M. Delarue,
D. Moras,
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摘要:
AbstractThe combined use of molecular and structural biology techniques has proved very efficient in elucidating structure‐function relationships in aminoacyl‐tRNA synthetases. Our present understanding of this family of enzymes is based on two main unifying principles: (i) division into two different classes, corresponding to two different modes of ATP binding and attachment of the activated amino acid to the last nucleotide of tRNA (either 2′OH or 3′OH of the ribose) by two different catalytic mechanisms and two structural domains with completely different folding, and (ii) the modular organization into separate and additional domains that we are just beginning to understand. Sequence analysis complements very nicely existing structural, biochemical and genetic results and makes them more general, leading to verifiable pred
ISSN:0265-9247
DOI:10.1002/bies.950151007
出版商:Wiley Subscription Services, Inc., A Wiley Company
年代:1993
数据来源: WILEY
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7. |
What the papers say: The p53‐mdm2autoregulatory feedback loop: A paradigm for the regulation of growth control by p53? |
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BioEssays,
Volume 15,
Issue 10,
1993,
Page 689-690
Steven M. Picksley,
David P. Lane,
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ISSN:0265-9247
DOI:10.1002/bies.950151008
出版商:Wiley Subscription Services, Inc., A Wiley Company
年代:1993
数据来源: WILEY
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8. |
What the papers say: Divergence in the role of MADS box genes in the determination of floral organ identity |
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BioEssays,
Volume 15,
Issue 10,
1993,
Page 691-693
Yongbiao Xue,
Gwyneth Ingram,
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ISSN:0265-9247
DOI:10.1002/bies.950151009
出版商:Wiley Subscription Services, Inc., A Wiley Company
年代:1993
数据来源: WILEY
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9. |
Problems and paradigms: Altering sex ratios: The games microbes play |
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BioEssays,
Volume 15,
Issue 10,
1993,
Page 695-697
Gregory D. D. Hurst,
Laurence D. Hurst,
Michael E. N. Majerus,
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摘要:
AbstractThe male gametes of most organisms lack cytoplasm. Consequently, most cytoplasmic genetic elements are maternally inherited: they cannot be transmitted patrilinnearly. The evolutionary interests of cytoplasmic elements therefore lie in transmission through the female. These elements may thus be in evolutionary conflict with nuclear genes which are transmitted by both sexes. This conflict is manifested in observations of cytoplasmically induced biased sex‐ratios. Some cytoplasmic genes avoid this fate by biasing the primary sex ratio towards females, or by inducing parthenogenesis. Others kill male hosts, and either achieve transmission via dispersal, or benefit their clonal relatives in the dead male's female siblings. Still others cause the failure of zygotes resulting from pairings between males carrying specific microbes and females lacking them, causing an increase in the microbes through the sterilisation of non‐bearing females. Many, but not all, of these ‘ultra‐selfish’ microbes are closely related. Investigations of the significance of their phylogenetic affinities, or lack of them, their adaptability in terms of the methods by which they avoid, or ameliorate, the adverse effects of being in male hosts, and their importance as selective agents in the evolution of invertebrate sex determination systems, provide fertile spheres for future
ISSN:0265-9247
DOI:10.1002/bies.950151010
出版商:Wiley Subscription Services, Inc., A Wiley Company
年代:1993
数据来源: WILEY
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10. |
Meetings: Germ line development |
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BioEssays,
Volume 15,
Issue 10,
1993,
Page 699-700
Adam S. Wilkins,
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ISSN:0265-9247
DOI:10.1002/bies.950151011
出版商:Wiley Subscription Services, Inc., A Wiley Company
年代:1993
数据来源: WILEY
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