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1.
Galanin is a neuropeptide with aminoacid length ranging from 29 to 31 is widely distributed in central and peripheral nervous system. Galanin controls various psychological processes such as sensation of pain, learning, feeding, and sexual behaviour. The N-terminal region of this neuropeptide has highly conserved 15 amino acids, which is triggered by galanin receptors. We performed evolutionary trace analysis for galanin sequences to gather information about functional residues. The consensus pattern given by the evolutionary trace (ET) analysis is supported by CLUSTALW and WEBLOGO results. Our observations strongly suggest the presence of functional residues in the N-terminal region of galanin for agonist-receptor binding.  相似文献   

2.
Lanosterol 14α-demethylase (CYP51) is an essential enzyme in the fungal life cycle and also an important target for the antifungal drug development. Based on the multiple sequence alignments of CYP51 family, an evolutionary tree of the CYP51 family was constructed by the evolutionary trace (ET) method. The identified trace residues could provide a reliable and rational guide to the design of CYP51 mutations and give more information about the detailed mechanism of substrate (drug) recognition and binding. The reliability of ET analysis to identify residues of functional importance was validated by the reported site-directed mutagenesis studies of CYP51s. Several residues in the active site were also validated by our mutagenesis studies. Mapping the identified trace residues onto the active site of the modeled structure of Candida albicans CYP51 (CACYP51) may provide useful information for the design of novel antifungal agents.  相似文献   

3.
Biological trace elements are needed in small quantities but are used by all living organisms. A growing list of trace element-dependent proteins and trace element utilization pathways highlights the importance of these elements for life. In this minireview, we focus on recent advances in comparative genomics of trace elements and explore the evolutionary dynamics of the dependence of user proteins on these elements. Many zinc protein families evolved representatives that lack this metal, whereas selenocysteine in proteins is dynamically exchanged with cysteine. Several other elements, such as molybdenum and nickel, have a limited number of user protein families, but they are strictly dependent on these metals. Comparative genomics of trace elements provides a foundation for investigating the fundamental properties, functions, and evolutionary dynamics of trace element dependence in biology.  相似文献   

4.
Joachimiak MP  Cohen FE 《Genome biology》2002,3(12):research0077.1-research007712

Background  

Details of functional speciation within gene families can be difficult to identify using standard multiple sequence alignment (MSA) methods. The evolutionary trace (ET) was developed as a visualization tool to combine MSA, phylogenetic and structural data for identification of functional sites in proteins. The method has been successful in extracting evolutionary details of functional surfaces in a number of biological systems and modifications of the method are useful in creating hypotheses about the function of previously unannotated genes. We wish to facilitate the graphical interpretation of disparate data types through the creation of flexible software implementations.  相似文献   

5.
The Origin of Bodyplans   总被引:3,自引:2,他引:1  
Paleontologists have documented the progressive originationof metazoan bodyplans beginning about 610 million years ago(Ma) with the major period of innovation occurring from 570Ma to about 525 Ma. The breadth of this event is now well documentedamong soft-bodied, skeletonized and trace fossils. Changes inboth the phytoplankton and in geochemical markers suggest pervasivetransformation of the environment during this interval, implicatingan ecological role in triggering this innovative burst. Theextent to which developmental innovations contributed to thisevolutionary burst requires placement of the protostome-deuterostomeancestor (PDA) in time: a PDA close to the radiation could indicatea greater role for developmental innovation. Molecular evidencepoints to a maximum age of about 670 Ma. Uncertainties overthe extent of functional homologies among the widely conserveddevelopmental control genes, and gene pathways, bracket plausibledates for such an ancestor: the maximally complex ancestor couldnot predate about 545 Ma; the least complex alternative coulddate to 575 Ma or even earlier. The nested hierarchical structureof developmental control genes and bodyplan originations suggestscertain temporal inhomogeneities to the evolutionary process:as certain developmental patterns are established they limitsubsequent evolutionary trajectories.  相似文献   

6.
There is an increasing role of population genetics in human genetic research linking empirical observations with hypotheses about sequence variation due to historical and evolutionary causes. In addition, the data sets are increasing in size, with genome-wide data becoming a common place in many empirical studies. As far as more information is available, it becomes clear that simplest hypotheses are not consistent with data. Simulations will provide the key tool to contrast complex hypotheses on real data by generating simulated data under the hypothetical historical and evolutionary conditions that we want to contrast. Undoubtedly, developing tools for simulating large sequences that at the same time allow simulate natural selection, recombination and complex demography patterns will be of great interest in order to better understanding the trace left on the DNA by different interacting evolutionary forces. Simulation tools will be also essential to evaluate the sampling properties of any statistics used on genome-wide association studies and to compare performance of methods applied at genome-wide scales. Several recent simulation tools have been developed. Here, we review some of the currently existing simulators which allow for efficient simulation of large sequences on complex evolutionary scenarios. In addition, we will point out future directions in this field which are already a key part of the current research in evolutionary biology and it seems that it will be a primary tool in the future research of genome and post-genomic biology.  相似文献   

7.
Traditional investigations of the evolution of human social and political institutions trace their ancestry back to nineteenth century social scientists such as Herbert Spencer, and have concentrated on the increase in socio-political complexity over time. More recent studies of cultural evolution have been explicitly informed by Darwinian evolutionary theory and focus on the transmission of cultural traits between individuals. These two approaches to investigating cultural change are often seen as incompatible. However, we argue that many of the defining features and assumptions of 'Spencerian' cultural evolutionary theory represent testable hypotheses that can and should be tackled within a broader 'Darwinian' framework. In this paper we apply phylogenetic comparative techniques to data from Austronesian-speaking societies of Island South-East Asia and the Pacific to test hypotheses about the mode and tempo of human socio-political evolution. We find support for three ideas often associated with Spencerian cultural evolutionary theory: (i) political organization has evolved through a regular sequence of forms, (ii) increases in hierarchical political complexity have been more common than decreases, and (iii) political organization has co-evolved with the wider presence of hereditary social stratification.  相似文献   

8.

Background

Evolution is everywhere in Galápagos, especially regarding the role the islands have played in the history of evolutionary thought. In turn, the Galápagos National Park guides are in a unique position as informal science educators, as they are the primary points-of-contact for the islands’ ~ 200,000 tourists per year. Our goal was to assess the guides’ knowledge and acceptance of the theory of evolution, in addition to learning more about their perceptions of the connection between the islands and evolution.

Methods

We surveyed 63 guides in three towns on three of the archipelago’s populated islands. Surveys included items targeting the guides knowledge of evolution (via the Knowledge of Evolution Exam, or the KEE) and acceptance of the theory of evolution (via the Measure of Acceptance of the Theory of Evolution, or the MATE). Additional, novel items gauged the guides’ perceptions of the islands, insofar as Galápagos is connected to evolution and the history of evolutionary thought.

Results

Although acceptance of evolution was high, knowledge was relatively low. However, the guides are proud of the islands’ association with the history of evolutionary thought, and enjoy talking about evolution while giving tours. On open-ended responses, guides claimed to especially enjoy talking with tourists about geology and island culture, and a few voiced concerns about the conflict between evolution and religion. Finally, the overwhelming majority of the guides agreed or strongly agreed with the statement, “I would like to learn more about Galápagos and the history of evolutionary thought.”

Conclusions

Galápagos guides display a disconnect between what is felt about evolution, and what is known about how evolution actually works. We can probably trace their fondness for, and acceptance of, evolution to the clear connection between evolution, tourism, and the guides’ livelihoods. We can trace their lack of knowledge to their schooling, as prior work detected similarly low knowledge of evolution in the islands’ schoolteachers. However, the guides are a receptive audience for professional development pertaining to our contemporary understanding of the mechanics of biological evolution. Improving guides’ understanding of biological evolution could, in turn, inform the evolutionary understanding of thousands of tourists each year.
  相似文献   

9.
Reddy DM 《Bioinformation》2007,1(9):370-375
Haemoglobins are found ubiquitously in eukaryotes and many bacteria. In plants, haemoglobins were first identified in species, which can fix nitrogen via symbiosis with bacteria. Recent findings suggest that another class of haemoglobins termed as nonsymbiotic haemoglobins are present through out the plant kingdom and are expressed differentially during plant development. Limited data available suggests that non-symbiotic haemoglobins are involved in hypoxic stress and oversupply of nutrients. Due to lack of information on structurally conserved, functionally important residues in non-symbiotic haemoglobins, further studies to elucidate the molecular mechanisms underlying the biological role are hampered. To determine functionally important residues in non-symbiotic haemoglobins, I have analyzed a number of sequences from plant haemoglobin family, in the context of the known crystal structures of plant by evolutionary trace method. Results indicate that the, evolutionary trace method like conventional phylogentic analysis, could resolve phylogentic relationships between plant haemoglobin family. Evolutionary trace analysis has identified candidate functional (trace) residues that uniquely characterize the heme-binding pocket, dimer interface and possible novel functional surfaces. Such residues from specific three-dimensional clusters might be of functional importance in nonsymbiotic haemoglobins. These data, together with our improved knowledge of possible functional residues, can be used in future structure-function analysis experiments.  相似文献   

10.
Zhu S  Huys I  Dyason K  Verdonck F  Tytgat J 《Proteins》2004,54(2):361-370
Scorpion alpha-K(+) channel toxins are a large family of polypeptides with a similar structure but diverse pharmacological activities. Despite many structural and functional data available at present, little progress has been made in understanding the toxin's molecular basis responsible for the functional diversification. In this paper, we report the first complete cDNA sequences of toxins belonging to subfamily 6 and identify five new members, called alpha-KTx 6.6-6.10. By analyzing the rates of mutations that occurred in the corresponding cDNAs, we suggest that accelerated evolution in toxin-coding regions may be associated with the functional diversification of this subfamily. To pinpoint sites probably involved in the functional diversity of alpha-KTx family, we analyzed this family of sequences using the evolutionary trace method. This analysis highlighted one channel-binding surface common for all the members. This surface is composed of one conserved lysine residue at position 29 assisted by other residues at positions 10, 26, 27, 32, 34, and 36. Of them, the positions 29, 32, and 34 have been reported to be the most major determinants of channel specificity. Interestingly, another contrary surface was also observed at a higher evolutionary time cut-off value, which may be involved in the binding of ERG (ether-a-go-go-related gene) channel-specific toxins. The good match between the trace residues and the functional epitopes of the toxins suggested that the evolutionary trace results reported here can be applied to predict channel-binding sites of the toxins. Because, the side-chain variation in the trace positions is strongly linked with the functional alteration and channel-binding surface transfer of alpha-KTx family, we conclude that our findings should also be important for the rational design of new toxins targeting a given potassium channel with high selectivity.  相似文献   

11.
Compared with Hennig's phylogenetical systematics which has as its aim the retracing of genealogical relations between taxonomic groups, evolutionary morphological systematics is equally justified. Classifications of basic plans, morphological types, and morphofunctional systems of organisms serve as the foundation of evolutionary morphological systems. They are constructed on the basis of thorough understanding and further iteration of morphological transformation in phylogenetical branches based on the constructional pecularities of the morphofunctional systems. The evolutionary morphological approach in systematics is important especially for elaborating macrosystems dealing with vastly divergant groups where it is impossible to trace their real genealogy. The general principles of evolutionary morphological systematics are considered. A variant of the classification system of the Plathelminthes is suggested.  相似文献   

12.
We re-examine the evolutionary dynamics of RNA secondary structures under directional selection towards an optimum RNA structure. We find that the punctuated equilibria lead to a very slow approach to the optimum, following on average an inverse power of the evolutionary time. In addition, our study of the trajectories shows that the out-of-equilibrium effects due to the evolutionary process are very weak. In particular, the distribution of genotypes is close to that arising during equilibrium stabilizing selection. As a consequence, the evolutionary dynamics leave almost no measurable out-of-equilibrium trace, only the transition genotypes (close to the border between different periods of stasis) have atypical mutational properties.  相似文献   

13.
微量元素指需要量很少(人体中含量在0.01%以下),但却是所有生物体所必需的元素。它们参与了生物体中各种复杂的生物过程,因此不同生物必须依赖相应的微量元素才能生存。过去大量的工作主要放在微量元素代谢通路和微量元素结合蛋白的实验研究上,由此凸显出微量元素对生命的重要性。然而,微量元素的计算生物学研究工作却非常有限。着重介绍当前利用比较基因组学的理论和方法来研究不同微量元素的利用、代谢、功能和进化方面问题的最新进展。对于所讨论的元素,大多数利用它们的蛋白已经基本确定,并且这些蛋白对于特定元素的依赖性也是非常保守的。通过比较基因组学分析,有助于帮助我们进一步认识微量元素领域很多基本问题(如在古菌、细菌和真核生物中的代谢、功能和动态进化规律等)及其重要特征。  相似文献   

14.
The elemental composition of phytoplankton is a fusion of the evolutionary history of the host and plastid, resulting in differences in genetic constraints and selection pressures associated with environmental conditions. The evolutionary inheritance hypothesis predicts similarities in elemental composition within related taxonomic lineages of phytoplankton. To test this hypothesis, we measured the elemental composition (C, N, P, S, K, Mg, Ca, Sr, Fe, Mn, Zn, Cu, Co, Cd and Mo) of 14 phytoplankton species and combined these with published data from 15 more species from both marine and freshwater environments grown under nutrient-replete conditions. The largest differences in the elemental profiles of the species distinguish between the prokaryotic Cyanophyta and primary endosymbiotic events that resulted in the green and red plastid lineages. Smaller differences in trace element stoichiometry within the red and green plastid lineages are consistent with changes in trace elemental stoichiometry owing to the processes associated with secondary endosymbioses and inheritance by descent with modification.  相似文献   

15.
MOTIVATION: Most proteins have evolved to perform specific functions that are dependent on the adoption of well-defined three-dimensional (3D) structures. Specific patterns of conserved residues in amino acid sequences of divergently evolved proteins are frequently observed; these may reflect evolutionary restraints arising both from the need to maintain tertiary structure and the requirement to conserve residues more directly involved in function. Databases of such sequence patterns are valuable in identifying distant homologues, in predicting function and in the study of evolution. RESULTS: A fully automated database of protein sequence patterns, Functional Protein Sequence Pattern Database (FPSPD), has been derived from the analysis of the conserved residues that are predicted to be functional in structurally aligned homologous families in the HOMSTRAD database. Environment-dependent substitution tables, evolutionary trace analysis, solvent accessibility calculations and 3D-structures were used to obtain the FPSPD. The method yielded 3584 patterns that are considered functional and 3049 patterns that are probably functional. FPSPD could be useful for assigning a protein to a homologous superfamily and thereby providing clues about function. AVAILABILITY: FPSPD is available at http://www-cryst.bioc.cam.ac.uk/~fpspd/  相似文献   

16.
Gu X 《Genetics》2004,167(1):531-542
Microarray technology has produced massive expression data that are invaluable for investigating the genome-wide evolutionary pattern of gene expression. To this end, phylogenetic expression analysis is highly desirable. On the basis of the Brownian process, we developed a statistical framework (called the E(0) model), assuming the independent expression of evolution between lineages. Several evolutionary mechanisms are integrated to characterize the pattern of expression diversity after gene duplications, including gradual drift and dramatic shift (punctuated equilibrium). When the phylogeny of a gene family is given, we show that the likelihood function follows a multivariate normal distribution; the variance-covariance matrix is determined by the phylogenetic topology and evolutionary parameters. Maximum-likelihood methods for multiple microarray experiments are developed, and likelihood-ratio tests are designed for testing the evolutionary pattern of gene expression. To reconstruct the evolutionary trace of expression diversity after gene (or genome) duplications, we developed a Bayesian-based method and use the posterior mean as predictors. Potential applications in evolutionary genomics are discussed.  相似文献   

17.
Comparative genetics, genomics and cytogenetics provide tools to trace the evolutionary history of extant genomes. Yet, the interpretation of rapidly increasing genomic data is not always done in agreement with constraints determined by chromosome structural features and by insights obtained from chromosome mutagenesis. The terms 'non-reciprocal chromosome translocation', 'chromosome fusion' and 'centromere shift' used to explain genomic differences among organisms are misleading and often do not correctly reflect the mechanisms of chromosome rearrangements underlying the evolutionary karyotypic variation. Here, we (re)interpret evolutionary genome alterations in a parsimonious way and demonstrate that results of comparative genomics and comparative chromosome painting can be explained on the basis of known primary and secondary chromosome rearrangements. Therefore, some widespread terms used in comparative and evolutionary genomics should be either avoided (e.g. non-reciprocal translocation) or redefined (e.g. chromosome fusion and centromere shift).  相似文献   

18.
The early studies of evolutionary developmental biology (Evo-Devo) come from several sources. Tributaries flowing into Evo-Devo came from such disciplines as embryology, developmental genetics, evolutionary biology, ecology, paleontology, systematics, medical embryology and mathematical modeling. This essay will trace one of the major pathways, that from evolutionary embryology to Evo-Devo and it will show the interactions of this pathway with two other sources of Evo-Devo: ecological developmental biology and medical developmental biology. Together, these three fields are forming a more inclusive evolutionary developmental biology that is revitalizing and providing answers to old and important questions involving the formation of biodiversity on Earth. The phenotype of Evo-Devo is limited by internal constraints on what could be known given the methods and equipment of the time and it has been framed by external factors that include both academic and global politics.  相似文献   

19.
基因组功能预测的进化印记方法   总被引:6,自引:1,他引:6  
改善基因组功能预测方案是目前功能基因组学的迫切问题,生物进化历程会在分子序列上留下相应进化印记-直系同源簇的特异模体,在这一生物学事实的基础上,提出了一个新的基因缚功能预测方法,首先利用进化分析方法构建直系同源簇,再找到各直系同源簇的功能模体,这样可以形成特异的功能模体库,未知基因的功能预测可望通过搜索该功能模体库而得以高效,准确地完成,对5个家族的检验初步证实该方案是可行的。  相似文献   

20.
A giant Paleodictyon gomezi with a maximum mesh diameter of 13 cm and covering more than 0.5 m2 occurs in the lower Eocene flysch near Zumaya. The giant Paleodictyon occurs with flute casts and, therefore, must have been produced deeply in the sediment. The lengthening of mesh cells parallel and perpendicular to the flute casts implies changing current directions during trace production. Rows of elongate and offset mesh cells reflect the row-by-row production of the trace; however, the base line followed by the trace fossil producer (meandering or spiral) cannot be reconstructed because of incomplete preservation. The extraordinary size of this giant Paleodictyon contradicts the evolutionary trend of deep-sea trace fossils toward optimization and miniaturization, since similar large Paleodictyon specimens occur in Silurian flysch.  相似文献   

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