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11.
RP Tucker K Drabikowski JF Hess J Ferralli R Chiquet-Ehrismann JC Adams 《BMC evolutionary biology》2006,6(1):60-17
Background
Tenascins are a family of glycoproteins found primarily in the extracellular matrix of embryos where they help to regulate cell proliferation, adhesion and migration. In order to learn more about their origins and relationships to each other, as well as to clarify the nomenclature used to describe them, the tenascin genes of the urochordate Ciona intestinalis, the pufferfish Tetraodon nigroviridis and Takifugu rubripes and the frog Xenopus tropicalis were identified and their gene organization and predicted protein products compared with the previously characterized tenascins of amniotes. 相似文献12.
Distinguishing morphologically cryptic taxa, by definition, requires genetic data such as DNA sequences. However, DNA sequences may not be obtained easily for taxa from remote sites. Here we provide the details of a high-resolution melt-curve-based method using taxon-specific primers that can distinguish two taxa of Adélie penguins, and that will be usable in Antarctica when combined with some of the newly developed field-deployable thermal cyclers. We suggest that the wider adoption of field-deployable polymerase-chain-reaction-based techniques will enable faster assignation of haplotype to individuals in situ, and so allow the targeting of observations and sample collection to specimens relevant to the research question. Targeting individuals will also reduce the need to repeatedly handle animals and reduce the time and travel required to complete field work. 相似文献
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14.
Attenuation of pattern recognition receptor signaling is mediated by a MAP kinase kinase kinase 下载免费PDF全文
Sharon C Mithoe Christina Ludwig Michiel JC Pel Mara Cucinotta Alberto Casartelli Malick Mbengue Jan Sklenar Paul Derbyshire Silke Robatzek Corné MJ Pieterse Ruedi Aebersold Frank LH Menke 《EMBO reports》2016,17(3):441-454
Pattern recognition receptors (PRRs) play a key role in plant and animal innate immunity. PRR binding of their cognate ligand triggers a signaling network and activates an immune response. Activation of PRR signaling must be controlled prior to ligand binding to prevent spurious signaling and immune activation. Flagellin perception in Arabidopsis through FLAGELLIN‐SENSITIVE 2 (FLS2) induces the activation of mitogen‐activated protein kinases (MAPKs) and immunity. However, the precise molecular mechanism that connects activated FLS2 to downstream MAPK cascades remains unknown. Here, we report the identification of a differentially phosphorylated MAP kinase kinase kinase that also interacts with FLS2. Using targeted proteomics and functional analysis, we show that MKKK7 negatively regulates flagellin‐triggered signaling and basal immunity and this requires phosphorylation of MKKK7 on specific serine residues. MKKK7 attenuates MPK6 activity and defense gene expression. Moreover, MKKK7 suppresses the reactive oxygen species burst downstream of FLS2, suggesting that MKKK7‐mediated attenuation of FLS2 signaling occurs through direct modulation of the FLS2 complex. 相似文献
15.
Anonymous nuclear DNA markers in the American oyster and their implications for the heterozygote deficiency phenomenon in marine bivalves 总被引:4,自引:0,他引:4
A puzzling population-genetic phenomenon widely reported in allozyme
surveys of marine bivalves is the occurrence of heterozygote deficits
relative to Hardy-Weinberg expectations. Possible explanations for this
pattern are categorized with respect to whether the effects should be
confined to protein-level assays or are genomically pervasive and expected
to be registered in both protein- and DNA-level assays. Anonymous nuclear
DNA markers from the American oyster were employed to reexamine the
phenomenon. In assays based on the polymerase chain reaction (PCR), two
DNA-level processes were encountered that can lead to artifactual genotypic
scorings: (a) differential amplification of alleles at a target locus and
(b) amplification from multiple paralogous loci. We describe symptoms of
these complications and prescribe methods that should generally help to
ameliorate them. When artifactual scorings at two anonymous DNA loci in the
American oyster were corrected, Hardy-Weinberg deviations registered in
preliminary population assays decreased to nonsignificant values.
Implications of these findings for the heterozygote-deficit phenomenon in
marine bivalves, and for the general development and use of PCR-based
assays, are discussed.
相似文献
16.
James M. Hempe Amanda M. McGehee Alexandre V. Stoyanov 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2009,877(28):3462-3466
Genetic variation in the number and reactivity of beta globin sulfhydryl groups causes variation in erythrocyte redox status in mouse populations. These experiments demonstrate the use of capillary isoelectric focusing for measuring endogenous S-glutathionyl hemoglobin and identifying mouse beta globin (Hbb) haplotype in inbred and outbred mouse strains with mono-cysteinyl or di-cysteinyl beta globins. Hbb haplotype can be readily determined in all strains based on characteristic differences in peak profiles or on peak mobility shift induced by thiol exchange with glutathione disulfide in vitro. This method could prove useful for in vivo study of factors that influence thiol protein modification. 相似文献
17.
Osbel Almora Derya Baran Guillermo C. Bazan Carlos I. Cabrera Sule Erten-Ela Karen Forberich Fei Guo Jens Hauch Anita W. Y. Ho-Baillie T. Jesper Jacobsson Rene A. J. Janssen Thomas Kirchartz Nikos Kopidakis Maria A. Loi Richard R. Lunt Xavier Mathew Michael D. McGehee Jie Min David B. Mitzi Mohammad K. Nazeeruddin Jenny Nelson Ana F. Nogueira Ulrich W. Paetzold Barry P. Rand Uwe Rau Henry J. Snaith Eva Unger Lídice Vaillant-Roca Chenchen Yang Hin-Lap Yip Christoph J. Brabec 《Liver Transplantation》2023,13(1):2203313
Following the 2nd release of the “Emerging PV reports,” the best achievements in the performance of emerging photovoltaic devices in diverse emerging photovoltaic research subjects are summarized, as reported in peer-reviewed articles in academic journals since August 2021. Updated graphs, tables, and analyses are provided with several performance parameters, e.g., power conversion efficiency, open-circuit voltage, short-circuit current density, fill factor, light utilization efficiency, and stability test energy yield. These parameters are presented as a function of the photovoltaic bandgap energy and the average visible transmittance for each technology and application, and are put into perspective using, e.g., the detailed balance efficiency limit. The 3rd installment of the “Emerging PV reports” extends the scope toward triple junction solar cells. 相似文献
18.
A comparative description of mitochondrial DNA differentiation in selected avian and other vertebrate genera 总被引:13,自引:1,他引:13
Levels of mitochondrial DNA (mtDNA) sequence divergence between species
within each of several avian (Anas, Aythya, Dendroica, Melospiza, and
Zonotrichia) and nonavian (Lepomis and Hyla) vertebrate genera were
compared. An analysis of digestion profiles generated by 13-18 restriction
endonucleases indicates little overlap in magnitude of mtDNA divergence for
the avian versus nonavian taxa examined. In 55 interspecific comparisons
among the avian congeners, the fraction of identical fragment lengths (F)
ranged from 0.26 to 0.96 (F = 0.46), and, given certain assumptions, these
translate into estimates of nucleotide sequence divergence (p) ranging from
0.007 to 0.088; in 46 comparisons among the fish and amphibian congeners, F
values ranged from 0.00 to 0.36 (F = 0.09), yielding estimates of P greater
than 0.070. The small mtDNA distances among avian congeners are associated
with protein-electrophoretic distances (D values) less than approximately
0.2, while the mtDNA distances among assayed fish and amphibian congeners
are associated with D values usually greater than 0.4. Since the
conservative pattern of protein differentiation previously reported for
many avian versus nonavian taxa now appears to be paralleled by a
conservative pattern of mtDNA divergence, it seems increasingly likely that
many avian species have shared more recent common ancestors than have their
nonavian taxonomic counterparts. However, estimates of avian divergence
times derived from mtDNA- and protein-calibrated clocks cannot readily be
reconciled with some published dates based on limited fossil remains. If
the earlier paleontological interpretations are valid, then protein and
mtDNA evolution must be somewhat decelerated in birds. The empirical and
conceptual issues raised by these findings are highly analogous to those in
the long-standing debate about rates of molecular evolution and times of
separation of ancestral hominids from African apes.
相似文献
19.
McGehee JC Tanner CJ Houmard JA 《Journal of strength and conditioning research / National Strength & Conditioning Association》2005,19(3):553-558
The purpose of this study was to examine the accuracy of tests that may be used by distance runners to estimate the lactate threshold. Competitive distance runners/triathletes (N = 27) performed a criterion test that directly measured (blood lactate of 4.0 mmol.L(-1)) the lactate threshold. Subjects then performed 4 tests (VDOT, 3,200-m time trial, 30-minute time trial, Conconi) that estimate the threshold. Mean estimations of the running velocity at the lactate threshold from the 30-minute time trial (standard error of the estimate, SEE, 0.21 m.s(-1)) and VDOT (SEE 0.41 m.s(-1)) methods did not differ (P>0.05) from the criterion. In terms of heart rate, the 30-minute time trial estimation did not significantly differ (SEE 8.0 b.min(-1)) from criterion. These findings suggest that the 30-minute time-trial method should be considered by coaches and distance runners/triathletes as a method for estimating both the running velocity and heart rate at the lactate threshold. 相似文献
20.