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Valentina Millarte Gaelle Boncompain Kerstin Tillmann Franck Perez Elizabeth Sztul Hesso Farhan 《Molecular biology of the cell》2015,26(12):2263-2278
The role of early secretory trafficking in the regulation of cell motility remains incompletely understood. Here we used a small interfering RNA screen to monitor the effects on structure of the Golgi apparatus and cell migration. Two major Golgi phenotypes were observed—fragmented and small Golgi. The latter exhibited a stronger correlation with a defect in cell migration. Among the small Golgi hits, we focused on phospholipase C γ1 (PLCγ1). We show that PLCγ1 regulates Golgi structure and cell migration independently of its catalytic activity but in a manner that depends on interaction with the tethering protein p115. PLCγ1 regulates the dynamics of p115 in the early secretory pathway, thereby controlling trafficking from the endoplasmic reticulum to the Golgi. Our results uncover a new function of PLCγ1 that is independent of its catalytic function and link early secretory trafficking to the regulation of cell migration. 相似文献
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Matthew T. Webster Nona Kamgari Michele Perloski Marc P. Hoeppner Erik Axelsson ?ke Hedhammar Gerli Pielberg Kerstin Lindblad-Toh 《BMC genomics》2015,16(1)
Background
The domestic dog is a rich resource for mapping the genetic components of phenotypic variation due to its unique population history involving strong artificial selection. Genome-wide association studies have revealed a number of chromosomal regions where genetic variation associates with morphological characters that typify dog breeds. A region on chromosome 10 is among those with the highest levels of genetic differentiation between dog breeds and is associated with body mass and ear morphology, a common motif of animal domestication. We characterised variation in this region to uncover haplotype structure and identify candidate functional variants.Results
We first identified SNPs that strongly associate with body mass and ear type by comparing sequence variation in a 3 Mb region between 19 breeds with a variety of phenotypes. We next genotyped a subset of 123 candidate SNPs in 288 samples from 46 breeds to identify the variants most highly associated with phenotype and infer haplotype structure. A cluster of SNPs that associate strongly with the drop ear phenotype is located within a narrow interval downstream of the gene MSRB3, which is involved in human hearing. These SNPs are in strong genetic linkage with another set of variants that correlate with body mass within the gene HMGA2, which affects human height. In addition we find evidence that this region has been under selection during dog domestication, and identify a cluster of SNPs within MSRB3 that are highly differentiated between dogs and wolves.Conclusions
We characterise genetically linked variants that potentially influence ear type and body mass in dog breeds, both key traits that have been modified by selective breeding that may also be important for domestication. The finding that variants on long haplotypes have effects on more than one trait suggests that genetic linkage can be an important determinant of the phenotypic response to selection in domestic animals.Electronic supplementary material
The online version of this article (doi:10.1186/s12864-015-1702-2) contains supplementary material, which is available to authorized users. 相似文献207.
Kerstin Jantke Christine Schleupner Uwe Andreas Schneider 《Biodiversity and Conservation》2011,20(3):581-605
Protected areas in the European Union under the Natura 2000 reserve system cover about 17 percent of the total land area.
Systematic evaluations of the effectiveness of the current reserve system have been scarce and restricted to regional assessments.
One reason for that may be the poor availability of comprehensive fine scale biodiversity data for the highly fragmented and
densely human-populated European continent. We apply recently developed modeling tools for systematic conservation planning
to conduct a detailed gap analysis using coarse scale species occurrence data. The employed mathematical model uses mixed
integer programming to determine the cost-minimizing distribution of habitat locations subject to biophysical, economic, and
policy restrictions. We include fine scale wetland habitat data as well as species-specific proxies for population density
and viable population threshold. First, we evaluate the performance of the current Natura 2000 system in covering endangered
wetland vertebrate species. Results show that five area-demanding vertebrates are not covered by the current reserve system.
Second, we identify potentials for expanding the network to move toward complete coverage for the considered species mostly
in countries of North-Eastern Europe. About 3 million hectares of additional reserve area at a cost of 107 million Euro per
year would be required to achieve coverage of all considered species. Third, we present spatially explicit priority regions
for a cost-effective expansion of the current reserve network. 相似文献
208.
Doebis C Menning A Neumann K Ghani S Schlawe K Lauer U Hamann A Huehn J Syrbe U 《Immunology and cell biology》2011,89(4):566-572
Although activation and subsequent expansion of naive CD4(+) T cells within lymph nodes is well characterized, the fate of T effector cells activated within peripheral tissues during secondary reactions is poorly defined. Therefore, we studied the recruitment, proliferation and egress of antigen-specific Th1 effector cells in comparison with nonspecific Th1 cells throughout a delayed-type hypersensitivity reaction (DTH). Although we observed a high turnover of Th1 effector cells with unspecific high-rate recruitment and CCR7-dependent egress from the inflamed tissue in the early, acute DTH phase, a strong, selective accumulation of antigen-specific T cells occurred during the chronic, late DTH phase. This was mainly based on local proliferation of CD4(+) effector cells within the DTH tissue and concomitant retention. Considering the strong CCR7-dependent Th cell egress found in this model, the reduced CCR7 expression on antigen-specific T cells isolated from late-phase DTH tissue most likely contributes to the retention of these cells within the tissue. Thus, peripheral tissues can support not only the proliferation of CD8(+) T cells, as recently shown, but also that of CD4(+) T effector cells, forming a pool of tissue-resident T cells. 相似文献
209.
Georgieva D Greunke K Arni RK Betzel C 《Zeitschrift für Naturforschung. C, Journal of biosciences》2011,66(5-6):305-312
Api SI and Api SII are serine proteases of the honeybee venom containing allergenic determinants. Each protease consists of two structural modules: an N-terminal CUB (Api SI) or a clip domain (Api SII) and a C-terminal serine protease-like (SPL) domain. Both domains are connected with a linker peptide. The knowledge about the structure and function of Api SI and Api SII is limited mainly to their amino acid sequences. We constructed 3-D models of the two proteases using their amino acid sequences and crystallographic coordinates of related proteins. The models of the SPL domains were built using the structure of the prophenoloxidase-activating factor (PPAF)-II as a template. For modelling of the Api SI CUB domain the coordinates of porcine spermadhesin PSP-I were used. The models revealed the catalytic and substrate-binding sites and the negatively charged residue responsible for the trypsin-like activity. IgE-binding and antigenic sites in the two allergens were predicted using the models and programs based on the structure of known epitopes. Api SI and Api SII show structural and functional similarity to the members of the PPAF-II family. Most probably, they are part of the defence system of Apis mellifera. 相似文献
210.
Mäthger LM Lohmann KJ Limpus CJ Fritsches KA 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2011,366(1565):757-762
Sea turtles undertake long migrations in the open ocean, during which they rely at least partly on magnetic cues for navigation. In principle, sensitivity to polarized light might be an additional sensory capability that aids navigation. Furthermore, polarization sensitivity has been linked to ultraviolet (UV) light perception which is present in sea turtles. Here, we tested the ability of hatchling loggerheads (Caretta caretta) to maintain a swimming direction in the presence of broad-spectrum polarized light. At the start of each trial, hatchling turtles, with their magnetic sense temporarily impaired by magnets, successfully established a steady course towards a light-emitting diode (LED) light source while the polarized light field was present. When the LED was removed, however, hatchlings failed to maintain a steady swimming direction, even though the polarized light field remained. Our results have failed to provide evidence for polarized light perception in young sea turtles and suggest that alternative cues guide the initial migration offshore. 相似文献