Cloning, Sequencing, and Expression of the Amelogenin Gene in Two Scincid Lizards

2006 ◽  
Vol 85 (2) ◽  
pp. 138-143 ◽  
Author(s):  
S. Delgado ◽  
M.-L. Couble ◽  
H. Magloire ◽  
J.-Y. Sire
Keyword(s):  
Rapid Evolution ◽  
Structure And Function ◽  
Enamel Matrix ◽  
Conserved Residues ◽  
Gene Coding ◽  
Enamel Structure ◽  
Enamel Protein ◽  
Sequencing And Expression ◽  
And Function

Our knowledge of the gene coding for amelogenin, the major enamel protein, is mainly based on mammalian sequences. Only two sequences are available in reptiles. To know whether the snake sequence is representative of the amelogenin condition in squamates, we have studied amelogenin in two scincid lizards. Lizard amelogenin possesses numerous conserved residues in the N- and C-terminal regions, but its central region is highly variable, even when compared with the snake sequence. This rapid evolution rate indicates that a single squamate sequence was not representative, and that comparative studies of reptilian amelogenins might be useful to detect the residues which are really important for amelogenin structure and function. Reptilian and mammalian enamel structure is roughly similar, but no data support amelogenin being similarly expressed during amelogenesis. By performing in situ hybridization using a specific probe, we showed that lizard ameloblasts express amelogenin as described during mammalian amelogenesis. However, we have not found amelogenin transcripts in odontoblasts. This indicates that full-length amelogenin is specific to enamel matrix, at least in this lizard.

scholarly journals Inter-species comparison of the orientation algorithm directing larval chemotaxis in the genus Drosophila

2021 ◽  
Author(s):  
Elie Fink ◽  
Matthieu Louis
Keyword(s):  
Neural Circuits ◽  
Rapid Evolution ◽  
Structure And Function ◽  
Olfactory Behavior ◽  
Species Comparison ◽  
Closely Related Species ◽  
Genetic Studies ◽  
Phenotypic Differences ◽  
Peripheral Olfactory System ◽  
And Function

Animals differ in their appearances and behaviors. While many genetic studies have addressed the origins of phenotypic differences between fly species, we are still lacking a quantitative assessment of the variability in the way different fly species behave. We tackled this question in one of the most robust behaviors displayed by Drosophila: chemotaxis. At the larval stage, Drosophila melanogaster navigate odor gradients by combining four sensorimotor routines in a multilayered algorithm: a modulation of the overall locomotor speed and turn rate; a bias in turning during down-gradient motion; a bias in turning toward the gradient; the local curl of trajectories toward the gradient ("weathervaning"). Using high-resolution tracking and behavioral quantification, we characterized the olfactory behavior of eight closely related species of the Drosophila group in response to 19 ecologically-relevant odors. Significant changes are observed in the receptive field of each species, which is consistent with the rapid evolution of the peripheral olfactory system. Our results reveal substantial inter-species variability in the algorithms directing larval chemotaxis. While the basic sensorimotor routines are shared, their parametric arrangements can vary dramatically across species. The present analysis sets the stage for deciphering the evolutionary relationships between the structure and function of neural circuits directing orientation behaviors in Drosophila.

scholarly journals Phylogeny of the Serpin Superfamily: Implications of Patterns of Amino Acid Conservation for Structure and Function

2000 ◽  
Vol 10 (12) ◽  
pp. 1845-1864
Author(s):  
James A. Irving ◽  
Robert N. Pike ◽  
Arthur M. Lesk ◽  
James C. Whisstock
Keyword(s):  
Sequence Data ◽  
Initial Point ◽  
Structure And Function ◽  
Conserved Residues ◽  
Consensus Analysis ◽  
The Family ◽  
Protein Sequence Data ◽  
And Function ◽  
Conserved Amino Acids ◽  
Genome Projects

We present a comprehensive alignment and phylogenetic analysis of the serpins, a superfamily of proteins with known members in higher animals, nematodes, insects, plants, and viruses. We analyze, compare, and classify 219 proteins representative of eight major and eight minor subfamilies, using a novel technique of consensus analysis. Patterns of sequence conservation characterize the family as a whole, with a clear relationship to the mechanism of function. Variations of these patterns within phylogenetically distinct groups can be correlated with the divergence of structure and function. The goals of this work are to provide a carefully curated alignment of serpin sequences, to describe patterns of conservation and divergence, and to derive a phylogenetic tree expressing the relationships among the members of this family. We extend earlier studies by Huber and Carrell as well as by Marshall, after whose publication the serpin family has grown functionally, taxonomically, and structurally. We used gene and protein sequence data, crystal structures, and chromosomal location where available. The results illuminate structure–function relationships in serpins, suggesting roles for conserved residues in the mechanism of conformational change. The phylogeny provides a rational evolutionary framework to classify serpins and enables identification of conserved amino acids. Patterns of conservation also provide an initial point of comparison for genes identified by the various genome projects. New homologs emerging from sequencing projects can either take their place within the current classification or, if necessary, extend it.

scholarly journals Structure prediction of crystals, surfaces and nanoparticles

2020 ◽  
Vol 378 (2186) ◽  
pp. 20190600
Author(s):  
Scott M. Woodley ◽  
Graeme M. Day ◽  
R. Catlow
Keyword(s):  
Machine Learning ◽  
Energy Function ◽  
Structure Prediction ◽  
Search Algorithm ◽  
Structure And Function ◽  
Current Status ◽  
Organic Systems ◽  
And Function

We review the current techniques used in the prediction of crystal structures and their surfaces and of the structures of nanoparticles. The main classes of search algorithm and energy function are summarized, and we discuss the growing role of methods based on machine learning. We illustrate the current status of the field with examples taken from metallic, inorganic and organic systems. This article is part of a discussion meeting issue ‘Dynamic in situ microscopy relating structure and function’.

scholarly journals Structure and function of a nitrifying biofilm as determined by in situ hybridization and the use of microelectrodes.

1996 ◽  
Vol 62 (12) ◽  
pp. 4641-4647 ◽  
Author(s):  
A Schramm ◽  
L H Larsen ◽  
N P Revsbech ◽  
N B Ramsing ◽  
R Amann ◽  
...  
Keyword(s):  
In Situ Hybridization ◽  
Structure And Function ◽  
And Function

Progress in ultrastructural and molecular analysis of the nuclear matrix

1992 ◽  
Vol 50 (1) ◽  
pp. 508-509
Author(s):  
Edward G. Fey
Keyword(s):  
Electron Microscopy ◽  
Nuclear Matrix ◽  
Structure And Function ◽  
Matrix Proteins ◽  
Rna Transcription ◽  
Nuclear Matrix Proteins ◽  
The Past ◽  
And Function

In the past few years, considerable advances have been made regarding the structure and function of the nuclear matrix. In the first half of this presentation, the field of nuclear matrix research will be summarized. Emphasis will be placed on those studies where molecular interactions are demonstrated in situ utilizing high resolution light and/or electron microscopy. Studies demonstrating the role of the nuclear matrix in DNA synthesis and replication, RNA transcription and processing, and the binding of matrix attachment regions to specific nuclear matrix proteins will be summarized.

scholarly journals Energetics of life on the deep seafloor

2012 ◽  
Vol 109 (38) ◽  
pp. 15366-15371 ◽  
Author(s):  
Craig R. McClain ◽  
Andrew P. Allen ◽  
Derek P. Tittensor ◽  
Michael A. Rex
Keyword(s):  
Carbon Flux ◽  
Regulatory Policy ◽  
Structure And Function ◽  
Chemical Energy ◽  
Metabolic Theory ◽  
Biological Organization ◽  
Biochemical Kinetics ◽  
Energy Limitation ◽  
And Function

With frigid temperatures and virtually no in situ productivity, the deep oceans, Earth’s largest ecosystem, are especially energy-deprived systems. Our knowledge of the effects of this energy limitation on all levels of biological organization is very incomplete. Here, we use the Metabolic Theory of Ecology to examine the relative roles of carbon flux and temperature in influencing metabolic rate, growth rate, lifespan, body size, abundance, biomass, and biodiversity for life on the deep seafloor. We show that the relative impacts of thermal and chemical energy change across organizational scales. Results suggest that individual metabolic rates, growth, and turnover proceed as quickly as temperature-influenced biochemical kinetics allow but that chemical energy limits higher-order community structure and function. Understanding deep-sea energetics is a pressing problem because of accelerating climate change and the general lack of environmental regulatory policy for the deep oceans.

In situ MRI of the structure and function of multiphase catalytic reactors

2005 ◽  
Vol 105 (3-4) ◽  
pp. 464-468 ◽  
Author(s):  
Igor V. Koptyug ◽  
Anna A. Lysova ◽  
Renad Z. Sagdeev ◽  
Valery A. Kirillov ◽  
Alexander V. Kulikov ◽  
...  
Keyword(s):  
Structure And Function ◽  
Catalytic Reactors ◽  
And Function

Summary of Application of Intelligent Materials in Building

2013 ◽  
Vol 357-360 ◽  
pp. 1093-1096
Author(s):  
En Yu Sun ◽  
Wan Li Bi
Keyword(s):  
External Environment ◽  
Structure And Function ◽  
System Failure ◽  
Local Damage ◽  
Bionic Design ◽  
In Situ Composite ◽  
Intelligent Material ◽  
Regeneration Mechanism ◽  
And Function

Intelligent material is a kind of multifunctional composite bionic design, can sense environmental conditions, through the sensor network, interest will be provided to the control system, to respond to take action. Self-diagnosis and through self-growth, in situ composite regeneration mechanism of system failure, repair some local damage or destroy; to the changing external environment and conditions, timely adjust its structure and function. Because of its relative to the performance of traditional materials with special excellent, with broad prospects for development.

Effects of hydroxylamine on microbial community structure and function of autotrophic nitrifying biofilms determined by in situ hybridization and the use of microelectrodes

2004 ◽  
Vol 49 (11-12) ◽  
pp. 61-68 ◽  
Author(s):  
T. Kindaichi ◽  
S. Okabe ◽  
H. Satoh ◽  
Y. Watanabe
Keyword(s):  
In Situ Hybridization ◽  
Community Structure ◽  
Microbial Community ◽  
Microbial Community Structure ◽  
Structure And Function ◽  
Ammonia Oxidizing Bacteria ◽  
Low Concentrations ◽  
Nitrite Oxidizing Bacteria ◽  
And Function

Effects of hydroxylamine (NH2OH), an intermediate of NH4+ oxidation, on microbial community structure and function of two autotrophic nitrifying biofilms fed with and without NH2OH were analyzed by a 16S rRNA approach and the use of microelectrodes. In the NH2OH-added biofilm, partial oxidation of NH4+ to NO2- was observed, whereas complete oxidation of NH4+ to NO3- was achieved in the control biofilm. In situ hybridization results revealed that no nitrite-oxidizing bacteria (NOB) hybridized with any specific probes were detected in the NH2OH-added biofilm. Thus, the addition of low concentrations of NH2OH (250 mM) completely inhibited the growth of NOB. Phylogenetic analysis of 16S rDNA indicated that the ammonia-oxidizing bacteria (AOB) detected in both biofilms were closely related to Nitrosomonas europaea, and that the clone sequences from both biofilm libraries have more than 99% similarity to each other. However, in situ hybridization results revealed that the addition of NH2OH changed the form of growth pattern of the dominant Nitrosomonas spp. from dense clusters mode to single scattered cells mode. Microelectrode measurements revealed that the average NH4+ consumption rate calculated in the NH2OH-added biofilm was two times higher than that in the control biofilm. This clearly demonstrated that the oxidation of NH4+ was stimulated by NH2OH addition.

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