共查询到20条相似文献,搜索用时 46 毫秒
1.
Cellular responses to mild heat stress 总被引:12,自引:0,他引:12
Since its discovery in 1962 by Ritossa, the heat shock response has been extensively studied by a number of investigators to understand the molecular mechanism underlying the cellular response to heat stress. The most well characterized heat shock response is induction of the heat shock proteins that function as molecular chaperones and exert cell cycle regulatory and anti-apoptotic activities. While most investigators have focused their studies on the toxic effects of heat stress in organisms such as severe heat stress-induced cell cycle arrest and apoptosis, the cellular response to fever-ranged mild heat stress has been rather underestimated. However, the cellular response to mild heat stress is likely to be more important in a physiological sense than that to severe heat stress because the body temperature of homeothermic animals increases by only 1–2°C during febrile diseases. Here we provide information that mild heat stress does have some beneficial role in organisms via positively regulating cell proliferation and differentiation, and immune response in mammalian cells.Received 14 May 2004; received after revision 2 August 2004; accepted 16 August 2004 相似文献
2.
Transient receptor potential (TRP) ion channels have been identified as cellular sensors responding to diverse external and
internal stimuli. This review will cover the TRPV subfamily that comprises vertebrate and invertebrate members. The six mammalian
TRPV channels were demonstrated to function in thermosensation, mechanosensation, osmosensation and Ca2+ uptake. Invertebrate TRPV channels, five in Caenorhabditis elegans and two in Drosophila, have been shown to play a role in mechanosensation, such as hearing and proprioception in Drosophila and nose touch in C. elegans, and in the response to osmotic and chemical stimuli in C. elegans. We will focus here on the role that TRPV ion channels play in mechanosensation and a related sensory (sub-)modality, osmosensation.
Received 2 May 2005; received after revision 30 July 2005; accepted 30 August 2005 相似文献
3.
U. Müller 《Cellular and molecular life sciences : CMLS》2006,63(9):961-962
Our understanding of the cellular and molecular mechanisms underlying learning and memory formation derives from studies of
species as diverse as worms, mollusks, insects, birds and mammals. Despite the quite different brain structures and neuronal
networks, the studies support the current notion that neuronal activity leads to changes in synaptic connections as the neural
substrate of behavioral plasticity. The analysis of the mechanisms underlying learning and memory formation reveals a surprisingly
high conservation between invertebrates and mammals, both at the behavioral as well as the molecular level. This special issue
provides an overview of the current knowledge on cellular and molecular processes underlying memory formation. The contributing
reviews summarize the findings in different organisms, such as Aplysia, Drosophila, honeybees and mammals, and discuss new approaches, developments and hypotheses all aimed at understanding how the nervous
system acquires, stores and retrieves information. 相似文献
4.
5.
A comparative view of insect circadian clock systems 总被引:1,自引:0,他引:1
6.
Royet J 《Cellular and molecular life sciences : CMLS》2004,61(5):537-546
Over the past years, parallel studies conducted in mammals and flies have emphasized the existence of common mechanisms regulating the vertebrate and invertebrate innate immune systems. This culminated in the discovery of the central role of the Toll pathway in Drosophila immunity and in the implication of Toll-like receptors (TLRs)/interleukin-1(IL-1) in the mammalian innate immune response. In spite of clear similarities, such as shared intracellular pathway components, important divergences are expected between the two groups, whose last common ancestor lived more than half a billion years ago. The most obvious discrepancies lie in the mode of activation of the signalling receptors by microorganisms. In mammals, TLRs are part of protein complexes which directly recognize microbe-associated patterns, whereas Drosophila Toll functions like a classical cytokine receptor rather than a pattern recognition receptor. Recent studies demonstrate that members of the evolutionarily conserved peptidoglycan recognition protein family play an essential role in microbial sensing during immune response of Drosophila.Received 26 June 2003; received after revision 29 July 2003; accepted 25 August 2003 相似文献
7.
Galat A 《Cellular and molecular life sciences : CMLS》2008,65(21):3481-3493
Extracellular domains of some cellular receptors expressed in the organisms at different levels of development belong to three-fingered
protein (TFP) fold. The Homo sapiens genome encodes at least 45 genes containing from one to three TFP domains (TFPDs), namely diverse paralogues of the Ly6 gene,
CD59 and the receptors of activins, bone morphogenetic proteins, Mullerian inhibiting substance and transforming growth factor-β.
C4.4a and urokinase/plasminogen activatory receptor contain two and three TFPD repeats, respectively. These diverse proteins
have a low overall sequence similarity with each other and their hydrophobicity levels vary to a considerable degree. It is
suggested that sequence differentiation within the TFPD led to distinct groups of proteins whose attributes were optimized
to fit both the physicochemical properties specific to their functional microenvironment and selective targeting of their
highly diversified extracellular cofactors.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Received 7 August 2008; accepted 29 August 2008 相似文献
8.
In all complex organisms, the peripheral nerves ensure the portage of information from the periphery to central computing
and back again. Axons are in part amazingly long and are accompanied by several different glial cell types. These peripheral
glial cells ensure electrical conductance, most likely nuture the long axon, and establish and maintain a barrier towards
extracellular body fluids. Recent work has revealed a surprisingly similar organization of peripheral nerves of vertebrates
and Drosophila. Thus, the genetic dissection of glial differentiation in Drosophila may also advance our understanding of basic principles underlying the development of peripheral nerves in vertebrates. 相似文献
9.
R. Ladenstein J.-O. Winberg J. Benach 《Cellular and molecular life sciences : CMLS》2008,65(24):3918-3935
The structure-function relationships of alcohol dehydrogenases from the large family of short-chain dehydrogenase/reductase
(SDR) enzymes are described. It seems that while mammals evolved with a medium-chain alcohol dehydrogenase family (MDR), fruit
flies utilized an ancestral SDR enzyme. They have modified its function into an efficient alcohol dehydrogenase to aid them
in colonizing the emerging ecological niches that appeared around 65 million years ago. To the scientific community, Drosophila has now served as a model organism for quite some time, and Drosophila alcohol dehydrogenase is one of the best-studied members of the SDR family. The availability of a number of high-resolution
structures, accurate and thorough kinetic work, and careful theoretical calculations have enabled an understanding of the
structure-function relationships of this metal-free alcohol dehydrogenase. In addition, these studies have given rise to various
hypotheses about the mechanism of action of this enzyme and contribute to the detailed knowledge of the large superfamily
of SDR enzymes. 相似文献
10.
Studies in mammals, including humans, have reported age-related changes in microbiota dynamics. A major challenge, however, is to dissect the cause and effect relationships involved. Invertebrate model organisms such as the fruit fly Drosophila and the nematode Caenorhabditis elegans have been invaluable in studies of the biological mechanisms of aging. Indeed, studies in flies and worms have resulted in the identification of a number of interventions that can slow aging and prolong life span. In this review, we discuss recent work using invertebrate models to provide insight into the interplay between microbiota dynamics, intestinal homeostasis during aging and life span determination. An emerging theme from these studies is that the microbiota contributes to cellular and physiological changes in the aging intestine and, in some cases, age-related shifts in microbiota dynamics can drive health decline in aged animals. 相似文献
11.
A. Beqqali W. van Eldik C. Mummery R. Passier 《Cellular and molecular life sciences : CMLS》2009,66(5):800-813
Studies on identification, derivation and characterization of human stem cells in the last decade have led to high expectations
in the field of regenerative medicine. Although it is clear that for successful stem cell-based therapy several obstacles
have to be overcome, other opportunities lay ahead for the use of human stem cells. A more immediate application would be
the development of human models for cell-type specific differentiation and disease in vitro. Cardiomyocytes can be generated from stem cells, which have been shown to follow similar molecular events of cardiac development
in vivo. Furthermore, several monogenic cardiovascular diseases have been described, for which in vitro models in stem cells could be generated. Here, we will discuss the potential of human embryonic stem cells, cardiac stem
cells and the recently described induced pluripotent stem cells as models for cardiac differentiation and disease.
Received 07 August 2008; received after revision 26 September 2008; accepted 03 October 2008 相似文献
12.
The recent identification of candidate receptor genes for sweet, umami and bitter taste in mammals has opened a door to elucidate the molecular and neuronal mechanisms of taste. Drosophila provides a suitable system to study the molecular, physiological and behavioral aspects of taste, as sophisticated molecular genetic techniques can be applied. A gene family for putative gustatory receptors has been found in the Drosophila genome. We discuss here current knowledge of the gustatory physiology of Drosophila. Taste cells in insects are primary sensory neurons whereupon each receptor neuron responds to either sugar, salt or water. We found that particular tarsal gustatory sensilla respond to bitter compounds. Electrophysiological studies indicate that gustatory sensilla on the labellum and tarsi are heterogeneous in terms of their taste sensitivity. Determination of the molecular bases for this heterogeneity could lead to an understanding of how the sensory information is processed in the brain and how this in turn is linked to behavior.Received 12 May 2003; received after revision 9 June 2003; accepted 13 June 2003 相似文献
13.
R.E. Williamson J.E. Burn C.H. Hocart 《Cellular and molecular life sciences : CMLS》2001,58(10):1475-1490
Cellulose microfibrils containing crystalline β-1,4-glucan provide the major structural framework in higher-plant cell walls. Genetic analyses of Arabidopsis thaliana now link specific genes to plant cellulose production just as was achieved some years earlier with bacteria. Cellulose-deficient
mutants have defects in several members of one family within a complex glycosyltransferase superfamily and in one member of
a small family of membrane-bound endo-1,4-β-glucanases. The mutants also accumulate a readily extractable β-1,4-glucan that has short chains which, in at least one case, are lipid linked. Cellulose could be made by direct extension
of the glucan chain by the glycosyltransferase or, as the mutant suggests, by an indirect route which makes lipid-linked oligosaccharides.
Models discussed incorporate the known enzymes and lipo-glucan and raise the possibility that different CesA glycosyltransferases
may catalyse different steps.
Received 5 January 2001; received after revision 25 April 2001; accepted 25 April 2001 相似文献
14.
Protein-O-mannosyltransferases (Pmt proteins) catalyse the addition of mannose to serine or threonine residues of secretory proteins.
This modification was described first for yeast and later for other fungi, mammals, insects and recently also for bacteria.
O-mannosylation depends on specific isoforms of the three Pmt1, 2 and 4 subfamilies. In fungi, O-mannosylation determines the structure and integrity of cell walls, as well as cellular differentiation and virulence. O-mannosylation of specific secretory proteins of the human fungal pathogen Candida albicans and of the bacterial pathogen Mycobacterium tuberculosis contributes significantly to virulence. In mammals and insects, Pmt proteins are essential for cellular differentiation and
development, while lack of Pmt activity causes Walker-Warburg syndrome (muscular dystrophy) in humans. The susceptibility
of human cells to certain viruses may also depend on O-mannosyl chains. This review focuses on the various roles of Pmt proteins in cellular differentiation, development and virulence.
Received 6 September 2007; received after revision 3 October 2007; accepted 5 October 2007 相似文献
15.
Pharmacological studies with drugs that activate or inhibit several protein kinase C (PKC) isozymes have identified the PKC family of serine-threonine kinases as important in the regulation of -aminobutyric acid type A (GABAA) receptor function. PKC modulates GABAA receptor surface density, chloride conductance and receptor sensitivity to positive allosteric modulators such as neurosteroids, ethanol, benzodiazepines and barbiturates. Recent studies using PKC isozyme-selective reagents and gene-targeted mice have begun to identify critical roles for three isozymes, PKCII, PKC and PKC, in various aspects of GABAA receptor regulation. Progress in this field touches upon therapeutic areas that are of great clinical importance such as anxiety and addiction. Increased understanding of how PKC regulates GABAA receptors and which PKC isozymes are involved holds promise for development of new treatments for diverse neuropsychiatric disorders.Received 2 August 2004; received after revision 17 August 2004; accepted 21 August 2004 相似文献
16.
DNA transposons in vertebrate functional genomics 总被引:7,自引:0,他引:7
Miskey C Izsvák Z Kawakami K Ivics Z 《Cellular and molecular life sciences : CMLS》2005,62(6):629-641
Genome sequences of many model organisms of developmental or agricultural importance are becoming available. The tremendous amount of sequence data is fuelling the next phases of challenging research: annotating all genes with functional information, and devising new ways for the experimental manipulation of vertebrate genomes. Transposable elements are known to be efficient carriers of foreign DNA into cells. Notably, members of the Tc1/mariner and the hAT transposon families retain their high transpositional activities in species other than their hosts. Indeed, several of these elements have been successfully used for transgenesis and insertional mutagenesis, expanding our abilities in genome manipulations in vertebrate model organisms. Transposon-based genetic tools can help scientists to understand mechanisms of embryonic development and pathogenesis, and will likely contribute to successful human gene therapy. We discuss the possibilities of transposon-based techniques in functional genomics, and review the latest results achieved by the most active DNA transposons in vertebrates. We put emphasis on the evolution and regulation of members of the best-characterized and most widely used Tc1/mariner family.Received 8 June 2004; received after revision 26 October 2004; accepted 18 November 2004 相似文献
17.
Assel Mussabekova Laurent Daeffler Jean-Luc Imler 《Cellular and molecular life sciences : CMLS》2017,74(11):2039-2054
The fruit fly Drosophila melanogaster has been a valuable model to investigate the genetic mechanisms of innate immunity. Initially focused on the resistance to bacteria and fungi, these studies have been extended to include antiviral immunity over the last decade. Like all living organisms, insects are continually exposed to viruses and have developed efficient defense mechanisms. We review here our current understanding on antiviral host defense in fruit flies. A major antiviral defense in Drosophila is RNA interference, in particular the small interfering (si) RNA pathway. In addition, complex inducible responses and restriction factors contribute to the control of infections. Some of the genes involved in these pathways have been conserved through evolution, highlighting loci that may account for susceptibility to viral infections in humans. Other genes are not conserved and represent species-specific innovations. 相似文献
18.
Royet J 《Cellular and molecular life sciences : CMLS》2011,68(22):3651-3660
Insects mostly develop on decaying and contaminated organic matter and often serve as vectors of biologically transmitted
diseases by transporting microorganisms to the plant and animal hosts. As such, insects are constantly ingesting microorganisms,
a small fraction of which reach their epithelial surfaces, mainly their digestive tract, where they can establish relationships
ranging from symbiosis to mutualism or even parasitism. Understanding the tight physical, genetic, and biochemical interactions
that takes place between intestinal epithelia and either resident or infectious microbes has been a long-lasting objective
of the immunologist. Research in this field has recently been re-vitalized with the development of deep sequencing techniques,
which allow qualitative and quantitative characterization of gut microbiota. Interestingly, the recent identification of regenerative
stem cells in the Drosophila gut together with the initial characterization of Drosophila gut microbiota have opened up new avenues of study aimed at understanding the mechanisms that regulate the dialog between
the Drosophila gut epithelium and its microbiota of this insect model. The fact that some of the responses are conserved across species
combined with the power of Drosophila genetics could make this organism model a useful tool to further elucidate some aspects of the interaction occurring between
the microbiota and the human gut. 相似文献
19.
E. Christians E. Michel J.-P. Renard 《Cellular and molecular life sciences : CMLS》1997,53(2):168-176
Heat shock genes are found in all organisms, and synthesis of heat shock proteins is induced by various stressors in nearly
all the cells forming these organisms. However, a particular situation is noticed for hsp70 genes in mouse embryos at the beginning of their development. First, spontaneous expression of hsp70 is observed at the onset of zygotic genome activity. Second, inducible expression is delayed until morula or early blastocyst
stages. A better understanding of both these points depends on a more careful analysis of hsp70 expression in relation to their major regulators, the heat shock factors. In this review, we will see how the development
of the preimplanta tion embryo highlights the complexity of heat shock gene regulation involving trans-cis interactions and the cellular and nuclear environment. 相似文献
20.
Major alterations in genetic activity have been observed in every organism after exposure to abnormally high temperatures. This phenomenon, called the heat shock response, was discovered in the fruit flyDrosophila. Studies with this organism led to the discovery of the heat shock proteins, whose genes were among the first eukaryotic genes to be cloned. Several of the most important aspects of the regulation of the heat shock response and of the functions of the heat shock proteins have been unraveled inDrosophila. 相似文献