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1.
The advancement of immunocytochemistry (ICC) allows one to observe detailed spatial distribution of cellular antigens, but,
with some limitations. Using conventional ICC, it is difficult to distinguish the nuclear localization from cytoplasm, as
two large subcellular compartments overlap on the z-axis. In this study, we have investigated whether in situ immunostaining of ‘naked’ nuclei could provide an unambiguous method
for detection of nuclear antigens. We have designed a protocol that efficiently lyses plasmalemma, while keeping the nuclear
envelope intact. The optimal condition for lysing the plasmalemma was 0.5% Nonidet P-40 for 5 min in both neuronal and non-neuronal
cultured cells. Using this protocol, we could unambiguously isolate nuclear from cytoplasmic ICC signals. Since the present
protocol has been designed for immunostaining of ‘naked’ nuclei from cultured or isolated cells, we have coined a new term
to refer to this procedure as ‘immunonucleochemistry’ (‘INC’ for abbreviation). 相似文献
2.
A parentage study of closely related Ukrainian wine grape varieties using microsatellite markers 总被引:1,自引:0,他引:1
S. Goryslavets V. Risovanna R. Bacilieri J. -F. Hausman M. Heuertz 《Cytology and Genetics》2010,44(2):95-102
Four bred grapevine varieties released for commercial cultivation in Ukraine, namely ‘Antey Magarachskii’, ‘Rubinovyi Magaracha’,
‘Granatovyi Magaracha’ and ‘Rubin Golodrigi’, and their putative parental forms were genotyped using six microsatellite loci.
Genotypes were compared with breeding records to verify genetic relationships among varieties. Results of the analysis confirmed
four of six parent-offspring relationships. Results of the analysis allow to assume that genotype ‘Seyve Villard 20347’ is
the direct parent of ‘Antey Magarachskii’ instead of its grandparent. The first-studied accession believed to be that of ‘Granatovyi
Magaracha’ was identified as impurity. In order to verify the parentage of ‘Granatovyi Magaracha’, rest accessions of that
variety and its putative parent ‘Antey Magarachskii’ were additionally genotyped at 13 nuclear loci and at three chloroplast
loci. The parent-offspring relationship was confirmed, as all ‘Granatovyi Magaracha’ accessions had a common allele with the
parent variety ‘Antey Magarachskii’ at each locus and the same chlorotype A. Different ‘Granatovyi Magaracha’ accessions could
have been obtained via vegetative propagation of two seedlings which arose from one crossing. 相似文献
3.
Jones H Bernole A Jensen LB Horsnell RA Law JR Cooke RJ Norris CE 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2008,117(8):1335-1344
The construction of large-scale databases of molecular profiles of plant varieties for variety identification and diversity
analyses is of considerable interest. When varieties of an allogamous species such as oilseed rape are analysed and described
using molecular markers such as microsatellites, care is needed to represent the variety in a meaningful yet useful way. It
is possible to characterise such heterogeneous genotypes by analysing bulked samples comprising more than one individual seed
or plant, but this approach may result in complex microsatellite profiles. Intuitively it would be reasonable to represent
a variety by the common ‘major alleles’ in a profile, but how to define these ‘major alleles’ remains problematic. This paper
describes methods of analysing DNA microsatellite data that will allow independent and objective data production at a number
of laboratories. Methods for establishing allele scoring rules (thresholding) are described and the effect of these rules
on the utility of the data is discussed. 相似文献
4.
Christophe Malaterre 《Origins of life and evolution of the biosphere》2010,40(2):169-177
The plurality of definitions of life is often perceived as an unsatisfying situation stemming from still incomplete knowledge
about ‘what it is to live’ as well as from the existence of a variety of methods for reaching a definition. For many, such
plurality is to be remedied and the search for a unique and fully satisfactory definition of life pursued. In this contribution
on the contrary, it is argued that the existence of such a variety of definitions of life undermines the very feasibility
of ever reaching a unique unambiguous definition. It is argued that focusing on the definitions of specific types of ‘living
systems’—somehow in the same way that one can define specific types of ‘flying systems’—could be more fruitful from a heuristic
point of view than looking for ‘the’ right definition of life, and probably more accurate in terms of carving Nature at its
joints. 相似文献
5.
Jason Pierson Musa Sani Cveta Tomova Susan Godsave Peter J. Peters 《Histochemistry and cell biology》2009,132(3):253-262
The cellular nanocosm is made up of numerous types of macromolecular complexes or biological nanomachines. These form functional modules that are
organized into complex subcellular networks. Information on the ultra-structure of these nanomachines has mainly been obtained
by analyzing isolated structures, using imaging techniques such as X-ray crystallography, NMR, or single particle electron
microscopy (EM). Yet there is a strong need to image biological complexes in a native state and within a cellular environment,
in order to gain a better understanding of their functions. Emerging methods in EM are now making this goal reachable. Cryo-electron
tomography bypasses the need for conventional fixatives, dehydration and stains, so that a close-to-native environment is
retained. As this technique is approaching macromolecular resolution, it is possible to create maps of individual macromolecular
complexes. X-ray and NMR data can be ‘docked’ or fitted into the lower resolution particle density maps to create a macromolecular
atlas of the cell under normal and pathological conditions. The majority of cells, however, are too thick to be imaged in
an intact state and therefore methods such as ‘high pressure freezing’ with ‘freeze-substitution followed by room temperature
plastic sectioning’ or ‘cryo-sectioning of unperturbed vitreous fully hydrated samples’ have been introduced for electron
tomography. Here, we review methodological considerations for visualizing nanomachines in a close-to-physiological, cellular
context. EM is in a renaissance, and further innovations and training in this field should be fully supported.
Robert Feulgen Lecture 2009 presented at the 51st symposium of the Society for Histochemistry in Stubai, Austria, October
7–10, 2009. 相似文献
6.
Jason A. Clark 《Biology & philosophy》2010,25(1):75-94
In the last 10 years, several authors including Griffiths and Matthen have employed classificatory principles from biology
to argue for a radical revision in the way that we individuate psychological traits. Arguing that the fundamental basis for
classification of traits in biology is that of ‘homology’ (similarity due to common descent) rather than ‘analogy’, or ‘shared
function’, and that psychological traits are a special case of biological traits, they maintain that psychological categories
should be individuated primarily by relations of homology rather than in terms of shared function. This poses a direct challenge
to the dominant philosophical view of how to define psychological categories, viz., ‘functionalism’. Although the implications
of this position extend to all psychological traits, the debate has centered around ‘emotion’ as an example of a psychological
category ripe for reinterpretation within this new framework of classification. I address arguments by Griffiths that emotions
should be divided into at least two distinct classes, basic emotions and higher cognitive emotions, and that these two classes
require radically different theories to explain them. Griffiths argues that while basic emotions in humans are homologous
to the corresponding states in other animals, higher cognitive emotions are dependent on mental capacities unique to humans,
and are therefore not homologous to basic emotions. Using the example of shame, I argue that (a) many emotions that are commonly
classified as being higher cognitive emotions actually correspond to certain basic emotions, and that (b) the “higher cognitive
forms” of these emotions are best seen as being homologous to their basic forms. 相似文献
7.
Martin Maiden 《Morphology》2009,19(1):59-86
This study examines some cases of heteroclisis in the history of Romanian dialects, and concludes that the data call for a
reconsideration of Stump’s distinction (Language 82:279–322, 2006) between ‘cloven’ heteroclisis, where the intraparadigmatic
‘split’ is aligned with some morphosyntactic feature distinction, and ‘fractured’ heteroclisis, where this is not the case
and the pattern of heteroclisis is purely morphological. Stump’s account creates the impression that the ‘cloven’ variety
is universally predominant, and that the ‘fractured’ variety tends to follow very closely the available ‘cloven’ patterns
of the language. I shall suggest, instead, that the ‘fractured-only’ situation may in fact underlie heteroclisis cross-linguistically,
the phenomenon being in general sensitive not directly to morphosyntactic content, but rather to characteristic, and often
purely ‘morphomic’, patterns of stem-allomorphy.
Research for this paper was undertaken as part of the Arts and Humantities Research Council-funded project Autonomous Morphology in Diachrony: comparative evidence from the Romance Languages, currently being conducted at Oxford University. 相似文献
8.
Karthick Babu Sai Sankar Gupta 《Reviews in Environmental Science and Biotechnology》2009,8(4):313-316
Harvesting solar energy for human use has long been a cherished dream of scientists. Especially when unprecedented potentials
of biological systems are explored, they could shift the paradigm in the field of development of bio-electronic devices. Hence
artificial photosynthetic reaction centers can be potential ‘photovoltaic cells at molecular dimensions’. Understanding the
chemical environment, structure and dynamics plays an important role towards the effort of achieving an ‘artificial reaction
center’. Let us see how S. Karthick Babu, an EMBO student describes how ‘spin torch’ experiments are designed to chase this
dream. 相似文献
9.
Hans Mohr 《Journal of plant research》1988,101(1):79-101
The powerful technology for transferring functional foreign genes into plants can only express its potential to the extent
that our knowledge about signals and signal transmission in plants improves. In higher plants gene expression is regulated
by ‘signals from within’ and ‘signals from without’ (e.g., light). Since light-mediated changes provide the basis for much
of plant development, photocontrol of gene expression will mainly be considered. The recently discovered ‘plastidic factor’
will serve as the prototype of an intracellular ‘signal from within’. Particular emphasis will be laid on rapid interorgan
signal transmission since these novel observations suggest a revision of the presently held concepts about the means of communication
within a plant. It will be concluded in the end that the prevailing views about the nature of plants underestimate the degree
of sophistication actually exhibited by higher plants. 相似文献
10.
An earlier theory of cell differentiation and morphogenesis (Wassermann, 1972, 1973, 1978) is combined with the genetic control
model of Davidson and Britten (e.g. 1979). The resulting new theory suggests how, bysystematic process algorithms, specifically enumerated combinations of batteries of structural genes can become switched on in particularly enumerated
cells, via battery-specific enumerable regulator genes. The systematization is idealized. Up to a certain stage of development
in each mitotically arising cell a unique cell-specific combination of structural genes called ‘marker genes’ is active. Marker
genes are assumed to code for cell-specifying marker proteins (CSMPs) which permit cells carrying related markers to recognize
each other, thus permitting specific cell sorting.Batteries of marker genes could ensure great developmental precision and can safeguard—via redundancies of CSMP types—against accidental
loss or detrimental mutational modification of CSMPs or marker genes, respectively. This paper is much concerned with cell
lineage in relation to ‘microdifferentiation’, where ‘microdifferentiation’ of a cell refers to a cell's active marker genes
and its syntheses of CSMPs. A drastic distinction is made between ‘microdifferentiation’ and ‘gross’ differentiation of a
cell, where the same ‘gross’ differentiation may be shared by a large number of cells that could each be uniquely ‘microdifferentiated’.
Typical ‘gross’ differentiation could manifest itself in tissue specificity, whereas, up to certain stages of development,
all cells of the same gross differentiation type (say tissue specificity) could each be uniquely ‘microdifferentiated’. The
theory also assumes that at certain stages of the developmental process some (or in some organisms all) of the previously
uniquely specified cells could give rise to small (or occasionally large) clones of equispecified cells, some of which might
form clusters that represent complete ‘morphogenetic fields’ Tentative implementation mechanisms are proposed which suggest
how the theory could operate in molecular biological terms. In particular, CSMPs could endow cell surface membranes with a
highly specific protein network, and an associated equally specific cell surface coat. It is suggested how these highly specified
cell surface coats and other systems could provide an ‘extracellular guidance network’ which could help to direct cells to
attain energetically optimal locations relative to each other based on the matching of their surface specificities. In numerous
experimental situations, where normally present optimal matching of cells is excluded, ‘alternative matching’ based on experiment-specific
suboptimal matching could explain many data, notably in experimental development neurobiology (Wassermann, 1978). 相似文献
11.
The objective of this paper is the structural and narrative reconstruction of representations of ‘nature’, ‘wildlife’ and
‘landscape’, held by rural residents of the Dadia Forest Reserve. Data collection involved in-depth interviews. Employing
a social representations’ approach, we recovered representational elements that are expected in the case of rural belief systems,
such as negative dispositions towards wolves and foxes, as well as elements of an urban adherence, such as nature’s independence.
Representational elements refer to visual aspects of the countryside, which seem compatible with the figurative nucleus of
the rural idyll. Concerning ‘wildlife’, residents focused on vultures, which comprise the main tourist attraction of the reserve.
Scientific knowledge adds to the complexity of the narrative schema, which corresponds to the representation of ‘wildlife’.
Interviewees perceived the rural landscape as an interface between the natural and the human-conditioned environment. Our
study shows that interviewees make no reference to environmental conservation or quality of life issues, as it could be expected
according to relatively wide definitions of the term ‘environmentalism’. Environmental messages reinforced by ecotourism development
seem to be recalled primarily in terms of their compatibility with the perceived economic benefit of local people. Despite
ecotourism development, representational elements that diverge from a tourist version of ‘nature’, ‘wildlife’ and ‘landscape’
were not pronounced within rural belief-systems. Further interventions within the study area are needed, in order to address
a variety of topics under the environmental conservation discourse and raise the environmental awareness of rural residents. 相似文献
12.
A. Gallois J. C. Audran M. Burrus 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,97(1-2):211-219
We assessed the genetic relationships between members of the Fagaceae family by RAPDs in order to better ascertain the taxonomic status of a very particular population of Fagus sylvatica, the ‘tortuosa’ variety. Intra- and inter-population Nei and Li’s mean genetic distances were compared, and the genetic relationships
between individuals were clarified on dendrograms by the Neighbor joining method. RAPD analysis was first conducted on three
species from three genera, Quercus petraea, Castanea sativa, and Fagus sylvatica, in order to develop an efficient RAPD protocol. The variety level was then studied, and a general tendency of the individuals
to cluster by variety was observed. Individuals also clustered by geographic locations, but the genetic distances between
populations were not correlated to the distances between sites. Finally, we compared the common beech and ‘tortuosa’ varieties
from two different locations, Verzy and Süntel. Both populations from one location were closer than the same variety from
two sites. This last result is in agreement with those previously obtained with isozymes. Hypotheses concerning the origin
of the ‘tortuosa’ variety are discussed.
Received: 9 January 1998 / Accepted: 25 February 1998 相似文献
13.
Retrotransposon characterisation and fingerprinting of apple clones by S-SAP markers 总被引:4,自引:0,他引:4
Venturi S Dondini L Donini P Sansavini S 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2006,112(3):440-444
Retrotransposons have been found to comprise the most common class of transposable elements in eukaryotes and to occur in
high copy number in plant genomes. Several of these elements have been sequenced and were found to display a high degree of
heterogeneity and insertional polymorphism, both within and between species. The dispersion, ubiquity and prevalence of retrotransposons
in plant genomes provide an excellent basis for the development of marker systems and, hence, may be good molecular candidates
in distinguishing among apple clones, when they represent bud mutations of the original variety, considering that the random
amplified polymorphic DNA (RAPD), amplified fragment length polymorphism (AFLP) and simple sequence repeat (SSR) used thus
far in fingerprinting analyses have failed to meet discrimination expectations. The technique called sequence-specific amplified
polymorphism (S-SAP), which makes it possible to identify dominant markers for the detection of variation in the DNA flanking
the retrotransposon insertion site, was used in the present study to distinguish several clones of the cultivars ‘Gala’ and
‘Braeburn’ in apple fingerprinting. Moreover, our results suggest that the bud mutations, which have generated new patented
varieties of ‘Gala’ and ‘Braeburn’, appear to derive from retrotransposon insertion. 相似文献
14.
Zenghui Hu Yingbai Shen Fanyi Shen Youqing Luo Xiaohua Su 《Trees - Structure and Function》2009,23(5):1003-1011
Interplant communication has been widely demonstrated in plants, especially in herbaceous plants. In this study, mechanical
damage was shown to affect the levels of pyrochatechol, chlorogenic acid, gallic acid and p-hydroxyl benzoic acid in poplar (Populus simonii × P. pyramidalis ‘Opera 8277’) cuttings, indicating the activation of defense response. In neighboring intact cuttings, the levels of those
phenolics also varied when compared to the control, suggesting the interplant communication between poplar cuttings. Three
volatiles, methyl jasmonate, methyl salicylate and benzothiazole, were detected in volatiles emitted from mechanically damaged
poplar cuttings. All of them can induce changes in the levels of four phenolics. Therefore, they could act as airborne signals
between P. simonii × P. pyramidalis ‘Opera 8277’ cuttings. The different change patterns of phenolic contents induced by different volatiles imply that the defense
response activated in neighboring plants may be regulated by multiple signaling pathways. The results also suggest that the
entire defense response of plants involves a variety of airborne signals in wound-induced volatiles. 相似文献
15.
Sylvi Haldorsen Hasan Akan Bahattin ?elik Manfred Heun 《Vegetation History and Archaeobotany》2011,20(4):305-318
The domestication of the Neolithic founder crops of the Near East has recently been a topic of debate particularly with respect
to how rapidly the domestication of these crops occurred. One school of thought maintains that these processes lasted several
thousand years (‘protracted model’ with ‘gathering’, ‘cultivation’ and ‘domestication’ as three stages of a continuum, each
taking up to several thousand years), while another favors the view that domestication occurred much more quickly, over several
hundred years at most (‘rapid transition’). Our study focuses on one of these crops, 1-grained domesticated Einkorn wheat,
incorporating data from geology, vegetation history, and climate. In the Karacadağ region of southeastern Turkey, where 1-grained
Einkorn wheat was domesticated, the climate was severe (i.e. cold and dry) during the Younger Dryas. The climate of the Younger
Dryas acted as boundary during which a) conditions were not suitable for ‘cultivation’, and b) Einkorn would have retreated
to refugia exhibiting more suitable moisture-bearing soils that would have made ‘gathering’ difficult. Around 11600 cal. b.p., the Younger Dryas ended and a very rapid climatic amelioration commenced at the beginning of the Early Holocene, enabling
grasses to spread throughout the region. A ritual PPNA/PPNB site (G?bekli Tepe) and associated PPNB settlements such as Nevali
?ori and ?ay?nü were established at this time. In the settlements of Nevali ?ori and Cafer H?yük, the oldest domesticated
Einkorn was found in the earliest archaeological layers. This confirms that the inhabitants made use of domesticated 1-grained
Einkorn from the very beginning of settlement activity, although they continued to practice a mixed lifestyle as hunter-gatherers
and farmers. For ?ay?nü the issue is more complex, but here domesticated Einkorn also appears around the same time. In summary,
by 10400 cal. b.p. domesticated 1-grained Einkorn was present in large quantities at a variety of sites. This would give a maximum window of
time lasting approximately 1,200 years and is therefore not in agreement with the ‘protracted’ model but would be consistent
with a ‘rapid transition’. It is improbable that the ‘cultivation’ of wild Einkorn was practiced in the Karacadağ region,
since wild Einkorn was plentiful during the favorable growing conditions following the Younger Dryas, making it more likely
that ‘gathering’ would have been practiced. Because Einkorn has not been found in early settlements in the southern Levant,
this crop cannot have been ‘gathered’ and ‘cultivated’ there but instead was ‘domesticated’ independently and solely in southeastern
Turkey. Therefore, the YD acts as a boundary, providing a maximum time frame for 1-grained Einkorn domestication. 相似文献
16.
Gerald Kastberger Ronald Thenius Anton Stabentheiner Randall Hepburn 《Journal of Insect Behavior》2009,22(1):65-85
Colony defence in Apis mellifera involves a variety of traits ranging from ‘aggressive’ (e.g. entrance guarding, recruitment
of flying guards) to ‘docile’ (e.g. retreating into the nest) expression. We tested 11 colonies of three subspecies (capensis, scutellata, carnica) regarding their defensiveness. Each colony was selected as reportedly ‘aggressive’, ‘intermediate’ or ‘docile’ and consisted
of about 10,000 bees. We applied three stimulation regimes (mechanical disturbance, exposure to alarm pheromones, and the
combination of both) and measured their behaviours by tracking the rates of outflying bees at the entrance sites of the test
hives. We provided evidence that for mechanical disturbances the test colonies resolved into two response types, if the ‘immediate’
defence response, assessed in the first minute of stimulation, was taken as a function of foraging: ‘releaser’ colonies allocated flying guards, ‘retreater’ colonies reduced the outside-hive activities. This division was observed irrespective
of the subspecies membership and maintained in even roughly changing environmental conditions. However, if pheromone and mechanical
stimulation were combined, the variety of colony defensiveness restricted to two further types irrespective of the subspecies
membership: six of nine colonies degraded their rate of flying defenders with increasing foraging level, three of the colonies
extended their ‘aggressiveness’ by increasing the defender rate with the foraging level. Such ‘super-aggressive’ colonies
obviously are able to allocate two separate recruitment pools for foragers and flying defenders. 相似文献
17.
Soybean is an important agricultural crop and has, among its genotypes, a relatively wide variation in salt tolerance. As
measured by vegetative growth and yield, however, the achievement or failure of a high emergence ratio and seedling establishment
in saline soils can have significant economic implications in areas where soil salinity is a potential problem for soybean.
This study was conducted to determine the effects of salinity, variety and maturation rate on soybean emergence and seedling
growth. Included in the study were the variety ‘Manokin’; four near-isogenic sibling lines of the variety ‘Lee’ belonging
to maturity groups IV, V, VI and VII; and the variety ‘Essex’ and two of its near-isogenic related lines representing maturity
groups V, VI and VII, respectively. Field plots were salinized with sodium chloride and calcium chloride salts prior to planting.
The soybeans were irrigated with furrow irrigation which redistributed the salts towards the tail ends of the field plots.
Elevated soil salinity near the tail ends of the field significantly reduced soybean emergence rate, shoot height and root
length. No significant reduction was found for emergence or seedling growth of variety ‘Manokin’ when the electrical conductivity
of soil solution extract (ECe) was less than 3 dS m−1. Soybean emergence and seedling growth was significantly reduced when soil ECe reached about 11 dS m−1. Maturity groups V and VII of variety ‘Lee’ or V and VI of ‘Essex’ appeared to be more sensitive to salinity stress than
other maturity groups. Salt tolerance of different genotypes and maturity groups should be considered, among other limiting
factors, in minimizing salinity effects on soybean growth.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
18.
19.
Basal ganglia (BG) constitute a network of seven deep brain nuclei involved in a variety of crucial brain functions including:
action selection, action gating, reward based learning, motor preparation, timing, etc. In spite of the immense amount of
data available today, researchers continue to wonder how a single deep brain circuit performs such a bewildering range of
functions. Computational models of BG have focused on individual functions and fail to give an integrative picture of BG function.
A major breakthrough in our understanding of BG function is perhaps the insight that activities of mesencephalic dopaminergic
cells represent some form of ‘reward’ to the organism. This insight enabled application of tools from ‘reinforcement learning,’
a branch of machine learning, in the study of BG function. Nevertheless, in spite of these bright spots, we are far from the
goal of arriving at a comprehensive understanding of these ‘mysterious nuclei.’ A comprehensive knowledge of BG function has
the potential to radically alter treatment and management of a variety of BG-related neurological disorders (Parkinson’s disease,
Huntington’s chorea, etc.) and neuropsychiatric disorders (schizophrenia, obsessive compulsive disorder, etc.) also. In this
article, we review the existing modeling literature on BG and hypothesize an integrative picture of the function of these
nuclei. 相似文献