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101.
102.
Davit-Béal T Chisaka H Delgado S Sire JY 《Biological reviews of the Cambridge Philosophical Society》2007,82(1):49-81
Elucidation of the mechanisms controlling early development and organogenesis is currently progressing in several model species and a new field of research, evolutionary developmental biology, which integrates developmental and comparative approaches, has emerged. Although the expression pattern of many genes during tooth development in mammals is known, data on other lineages are virtually non-existent. Comparison of tooth development, and particularly of gene expression (and function) during tooth morphogenesis and differentiation, in representative species of various vertebrate lineages is a prerequisite to understand what makes one tooth different from another. Amphibians appear to be good candidates for such research for several reasons: tooth structure is similar to that in mammals, teeth are renewed continuously during life (=polyphyodonty), some species are easy to breed in the laboratory, and a large amount of morphological data are already available on diverse aspects of tooth biology in various species. The aim of this review is to evaluate current knowledge on amphibian teeth, principally concerning tooth development and replacement (including resorption), and changes in morphology and structure during ontogeny and metamorphosis. Throughout this review we highlight important questions which remain to be answered and that could be addressed using comparative morphological studies and molecular techniques. We illustrate several aspects of amphibian tooth biology using data obtained for the caudate Pleurodeles waltl. This salamander has been used extensively in experimental embryology research during the past century and appears to be one of the most favourable amphibian species to use as a model in studies of tooth development. 相似文献
103.
The identification of regulatory T (Treg) cells as important regulators of self-tolerance has opened up new therapeutic avenues for the treatment of several human diseases associated with Treg dysfunction, including autoimmune diseases and transplantation. Recent evidence indicates that vasoactive intestinal peptide (VIP), an anti-inflammatory neuropeptide with therapeutic potential in various immune disorders, participates in maintaining immune tolerance by a novel mechanism of inducing the generation of Treg cells. We propose a Treg-cell-based immunotherapy approach for resetting the balance of immune homeostasis, which takes advantage of novel functions of VIP in immunoregulation. 相似文献
104.
105.
Furlan Lopes Cassiane Lemos Costa Alice Dionísio Jaqueline Fernanda Delgado Cañedo Andres da Rosa Renata Del Valle Garnero Analia Inacio Ribeiro José Ricardo Gunski Ricardo José 《Genetica》2022,150(5):235-246
Genetica - Known as "electric-light bugs", belostomatids potentially act as agents of biological control. The Belostoma genus has holokinetic chromosomes, interspecific variation in... 相似文献
106.
Elena Ciani Emiliano Lasagna Mariasilvia D’Andrea Ingrid Alloggio Fabio Marroni Simone Ceccobelli Juan V. Delgado Bermejo Francesca M. Sarti James Kijas Johannes A. Lenstra Fabio Pilla the International Sheep Genomics Consortium 《遗传、选种与进化》2015,47(1)
Background
Merino and Merino-derived sheep breeds have been widely distributed across the world, both as purebred and admixed populations. They represent an economically and historically important genetic resource which over time has been used as the basis for the development of new breeds. In order to examine the genetic influence of Merino in the context of a global collection of domestic sheep breeds, we analyzed genotype data that were obtained with the OvineSNP50 BeadChip (Illumina) for 671 individuals from 37 populations, including a subset of breeds from the Sheep HapMap dataset.Results
Based on a multi-dimensional scaling analysis, we highlighted four main clusters in this dataset, which corresponded to wild sheep, mouflon, primitive North European breeds and modern sheep (including Merino), respectively. The neighbor-network analysis further differentiated North-European and Mediterranean domestic breeds, with subclusters of Merino and Merino-derived breeds, other Spanish breeds and other Italian breeds. Model-based clustering, migration analysis and haplotype sharing indicated that genetic exchange occurred between archaic populations and also that a more recent Merino-mediated gene flow to several Merino-derived populations around the world took place. The close relationship between Spanish Merino and other Spanish breeds was consistent with an Iberian origin for the Merino breed, with possible earlier contributions from other Mediterranean stocks. The Merino populations from Australia, New Zealand and China were clearly separated from their European ancestors. We observed a genetic substructuring in the Spanish Merino population, which reflects recent herd management practices.Conclusions
Our data suggest that intensive gene flow, founder effects and geographic isolation are the main factors that determined the genetic makeup of current Merino and Merino-derived breeds. To explain how the current Merino and Merino-derived breeds were obtained, we propose a scenario that includes several consecutive migrations of sheep populations that may serve as working hypotheses for subsequent studies.Electronic supplementary material
The online version of this article (doi:10.1186/s12711-015-0139-z) contains supplementary material, which is available to authorized users. 相似文献107.
M Montenegro S Llambí G Castro N Barlocco A Vadell V Landi JV Delgado A Martínez 《Genetics and molecular biology》2015,38(1):48-54
In this study, we genetically characterized the Uruguayan pig breed Pampa Rocha.
Genetic variability was assessed by analyzing a panel of 25 microsatellite markers
from a sample of 39 individuals. Pampa Rocha pigs showed high genetic variability
with observed and expected heterozygosities of 0.583 and 0.603, respectively. The
mean number of alleles was 5.72. Twenty-four markers were polymorphic, with 95.8% of
them in Hardy Weinberg equilibrium. The level of endogamy was low (FIS =
0.0475). A factorial analysis of correspondence was used to assess the genetic
differences between Pampa Rocha and other pig breeds; genetic distances were
calculated, and a tree was designed to reflect the distance matrix. Individuals were
also allocated into clusters. This analysis showed that the Pampa Rocha breed was
separated from the other breeds along the first and second axes. The
neighbour-joining tree generated by the genetic distances DA showed
clustering of Pampa Rocha with the Meishan breed. The allocation of individuals to
clusters showed a clear separation of Pampa Rocha pigs. These results provide
insights into the genetic variability of Pampa Rocha pigs and indicate that this
breed is a well-defined genetic entity. 相似文献
108.
Sib–sib or, more generally, family resemblance for dispersal seems a widespread characteristic of vertebrates, and the birthplace has the potential to shape the dynamics and features of animal populations. Dispersal studies have often stressed the fundamental link between the fate of dispersers and population dynamics, but few have focused on the dispersal directions of individuals, despite the profound implications that this may have on population distribution, structure, dynamics and viability. We investigated the directions followed by 72 radio‐tagged dispersers (43 males and 29 females from 14 nest sites) in an eagle owl Bubo bubo population, and assessed their a) inter‐individual distances during dispersal and b) age at dispersal departure. For siblings, as well as potential‐siblings (i.e. individuals born in the same nest in different years), the birthplace influenced inter‐individual distances and dispersal directions, i.e. dispersers from the same nest moved to similar locations during the study; moreover, in each year, individuals from the same birthplace moved across the same areas in a short time period. Finally, siblings and potential‐siblings born in the same nest in different years started dispersal at similar ages. Based on the movement patterns of dispersers we discuss: a) the potential implications of the birthplace‐dependent dispersal on the ideal free distribution theory, as well as in terms of kin competition, inbreeding avoidance and population dynamics; and, more generally, b) the effect of the temporal features of the natal dispersal on the concept of habitat suitability vs density of individuals developed by the ideal free distribution theory. 相似文献
109.
Escobar H Reyes-Vargas E Jensen PE Delgado JC Crockett DK 《Journal of proteome research》2011,10(5):2494-2507
Systematic investigation of cellular process by mass spectrometric detection of peptides obtained from proteins digestion or directly from immuno-purification can be a powerful tool when used appropriately. The true sequence of these peptides is defined by the interpretation of spectral data using a variety of available algorithms. However peptide match algorithm scoring is typically based on some, but not all, of the mechanisms of peptide fragmentation. Although algorithm rules for soft ionization techniques generally fit very well to tryptic peptides, manual validation of spectra is often required for endogenous peptides such as MHC class I molecules where traditional trypsin digest techniques are not used. This study summarizes data mining and manual validation of hundreds of peptide sequences from MHC class I molecules in publically available data files. We herein describe several important features to improve and quantify manual validation for these endogenous peptides--post automated algorithm searching. Important fragmentation patterns are discussed for the studied MHC Class I peptides. These findings lead to practical rules that are helpful when performing manual validation. Furthermore, these observations may be useful to improve current peptide search algorithms or development of novel software tools. 相似文献
110.
Fisher M Downie H Welten MC Delgado I Bain A Planzer T Sherman A Sang H Tickle C 《PloS one》2011,6(4):e18661
Hoxd13, Tbx2, Tbx3, Sall1 and Sall3 genes are candidates for encoding antero-posterior positional values in the developing chick wing and specifying digit identity. In order to build up a detailed profile of gene expression patterns in cell lineages that give rise to each of the digits over time, we compared 3 dimensional (3D) expression patterns of these genes during wing development and related them to digit fate maps. 3D gene expression data at stages 21, 24 and 27 spanning early bud to digital plate formation, captured from in situ hybridisation whole mounts using Optical Projection Tomography (OPT) were mapped to reference wing bud models. Grafts of wing bud tissue from GFP chicken embryos were used to fate map regions of the wing bud giving rise to each digit; 3D images of the grafts were captured using OPT and mapped on to the same models. Computational analysis of the combined computerised data revealed that Tbx2 and Tbx3 are expressed in digit 3 and 4 progenitors at all stages, consistent with encoding stable antero-posterior positional values established in the early bud; Hoxd13 and Sall1 expression is more dynamic, being associated with posterior digit 3 and 4 progenitors in the early bud but later becoming associated with anterior digit 2 progenitors in the digital plate. Sox9 expression in digit condensations lies within domains of digit progenitors defined by fate mapping; digit 3 condensations express Hoxd13 and Sall1, digit 4 condensations Hoxd13, Tbx3 and to a lesser extent Tbx2. Sall3 is only transiently expressed in digit 3 progenitors at stage 24 together with Sall1 and Hoxd13; then becomes excluded from the digital plate. These dynamic patterns of expression suggest that these genes may play different roles in digit identity either together or in combination at different stages including the digit condensation stage. 相似文献