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71.
Nora M. Casey Dan Milbourne Susanne Barth Melanie Febrer Glyn Jenkins Michael T. Abberton Charlotte Jones Daniel Thorogood 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2010,121(3):567-576
White clover (Trifolium repens L.) is a forage legume of considerable economic importance in temperate agricultural systems. It has a strong self-incompatibility
system. The molecular basis of self-incompatibility in T. repens is unknown, but it is under the control of a single locus, which is expressed gametophytically. To locate the self-incompatibility
locus (S locus) in T. repens, we carried out cross-pollination experiments in an F1 mapping population and constructed a genetic linkage map using amplified fragment length polymorphism and simple sequence
repeat markers. As the first step in a map-based cloning strategy, we locate for the first time the S locus in T. repens on a genetic linkage map, on the homoeologous linkage group pair 1 (E), which is broadly syntenic to Medicago truncatula L. chromosome 1. On the basis of this syntenic relationship, the possibility that the S locus may or may not possess an S-RNase gene is discussed. 相似文献
72.
Blake Ushijima Patrick Videau Andrew H. Burger Amanda Shore-Maggio Christina M. Runyon Mareike Sudek Greta S. Aeby Sean M. Callahan 《Applied and environmental microbiology》2014,80(7):2102-2109
Identification of a pathogen is a critical first step in the epidemiology and subsequent management of a disease. A limited number of pathogens have been identified for diseases contributing to the global decline of coral populations. Here we describe Vibrio coralliilyticus strain OCN008, which induces acute Montipora white syndrome (aMWS), a tissue loss disease responsible for substantial mortality of the coral Montipora capitata in Kāne‘ohe Bay, Hawai‘i. OCN008 was grown in pure culture, recreated signs of disease in experimentally infected corals, and could be recovered after infection. In addition, strains similar to OCN008 were isolated from diseased coral from the field but not from healthy M. capitata. OCN008 repeatedly induced the loss of healthy M. capitata tissue from fragments under laboratory conditions with a minimum infectious dose of between 107 and 108 CFU/ml of water. In contrast, Porites compressa was not infected by OCN008, indicating the host specificity of the pathogen. A decrease in water temperature from 27 to 23°C affected the time to disease onset, but the risk of infection was not significantly reduced. Temperature-dependent bleaching, which has been observed with the V. coralliilyticus type strain BAA-450, was not observed during infection with OCN008. A comparison of the OCN008 genome to the genomes of pathogenic V. coralliilyticus strains BAA-450 and P1 revealed similar virulence-associated genes and quorum-sensing systems. Despite this genetic similarity, infections of M. capitata by OCN008 do not follow the paradigm for V. coralliilyticus infections established by the type strain. 相似文献
73.
Two Dictyostelium orthologs of the prokaryotic cell division protein FtsZ localize to mitochondria and are required for the maintenance of normal mitochondrial morphology 下载免费PDF全文
Gilson PR Yu XC Hereld D Barth C Savage A Kiefel BR Lay S Fisher PR Margolin W Beech PL 《Eukaryotic cell》2003,2(6):1315-1326
In bacteria, the protein FtsZ is the principal component of a ring that constricts the cell at division. Though all mitochondria probably arose through a single, ancient bacterial endosymbiosis, the mitochondria of only certain protists appear to have retained FtsZ, and the protein is absent from the mitochondria of fungi, animals, and higher plants. We have investigated the role that FtsZ plays in mitochondrial division in the genetically tractable protist Dictyostelium discoideum, which has two nuclearly encoded FtsZs, FszA and FszB, that are targeted to the inside of mitochondria. In most wild-type amoebae, the mitochondria are spherical or rod-shaped, but in fsz-null mutants they become elongated into tubules, indicating that a decrease in mitochondrial division has occurred. In support of this role in organelle division, antibodies to FszA and FszA-green fluorescent protein (GFP) show belts and puncta at multiple places along the mitochondria, which may define future or recent sites of division. FszB-GFP, in contrast, locates to an electron-dense, submitochondrial body usually located at one end of the organelle, but how it functions during division is unclear. This is the first demonstration of two differentially localized FtsZs within the one organelle, and it points to a divergence in the roles of these two proteins. 相似文献
74.
Christina Nagel Regina Erber Natascha Ille Mareike von Lewinski Jörg Aurich Erich Möstl Christine Aurich 《Theriogenology》2014
External and internal stressors prolong parturition in different species. At parturition, sympathoadrenal activation should be avoided because an increased sympathetic tone may cause uterine atonia via β2-receptors. We hypothesized that at physiological parturition, horses are under parasympathetic dominance, and stress-response mechanisms are not activated during delivery of the foal. To evaluate stress responses, heart rate, heart rate variability, catecholamines, and cortisol were analyzed in mares (n = 17) throughout foaling. Heart rate decreased from 2 hours before (51 ± 1 beats/minute) to 2 hours after delivery (41 ± 2 beats/minute; P < 0.05). Heart rate variability variables, standard deviation of the beat-to-beat interval, and root mean square of successive beat-to-beat differences, changed over time (P < 0.05) with the highest values within 15 minutes after delivery. The number of mares with atrioventricular blocks and the number of atrioventricular blocks per mare increased over time (P < 0.01) and were significantly elevated from 15 minutes before to 45 minutes after birth of the foal. Salivary cortisol concentrations increased to a maximum at 30 minutes after delivery (25.0 ± 3.4 ng/mL; P < 0.01). Plasma epinephrine and norepinephrine concentrations showed significant fluctuations from rupture of the allantochorion to expulsion of the fetal membranes (P < 0.01) but were not markedly elevated at any time. In conclusion, mares give birth under high parasympathetic tone. Cortisol release during and after foaling is most likely part of the endocrine pathways regulating parturition and not a labor-associated stress response. 相似文献
75.
76.
RhoA exerts a permissive effect on volume-regulated anion channels in vascular endothelial cells 总被引:2,自引:0,他引:2
Carton I Trouet D Hermans D Barth H Aktories K Droogmans G Jorgensen NK Hoffmann EK Nilius B Eggermont J 《American journal of physiology. Cell physiology》2002,283(1):C115-C125
Cell swelling triggers in most cell typesan outwardly rectifying anion current,ICl,swell, via volume-regulated anion channels (VRACs). We have previously demonstrated in calf pulmonary artery endothelial (CPAE) cells that inhibition of the Rho/Rho kinase/myosin light chain phosphorylation pathway reduces the swelling-dependent activation of ICl,swell. However, theseexperiments did not allow us to discriminate between a direct activatorrole or a permissive effect. We now show that the Rho pathway did notaffect VRAC activity if this pathway was activated by transfecting CPAEcells with constitutively active isoforms of G (a Rho activatingheterotrimeric G protein subunit), Rho, or Rho kinase. Furthermore,biochemical and morphological analysis failed to demonstrate activationof the Rho pathway during hypotonic cell swelling. Finally,manipulating the Rho pathway with either guanosine5'-O-(3-thiotriphosphate) or C3 exoenzyme had no effect onVRACs in caveolin-1-expressing Caco-2 cells. We conclude that the Rhopathway exerts a permissive effect on VRACs in CPAE cells, i.e.,swelling-induced opening of VRACs requires a functional Rho pathway,but not an activation of the Rho pathway. 相似文献
77.
Molecular chaperone proteins play a pivotal role in the protozoan parasite Leishmania donovani, controlling cell fate and ensuring intracellular survival. In higher eukaryotes, the so-called co-chaperone proteins are
required for client protein recognition and proper function of chaperones, among them the small glutamine-rich tetratricopeptide
repeat proteins (SGT) which interact with both HSP70 and HSP90 chaperones. An atypical SGT homolog is found in the L. donovani genome, encoding a protein lacking the C-terminal glutamine-rich region, normally typical for SGT family members. The gene
is expressed constitutively during the life cycle and is essential for survival and/or growth of the parasites. LdSGT forms
large, stable complexes that also include another putative co-chaperone, HSC70 interacting protein (HIP). The gene product
forms cytoplasmic clusters, matching the subcellular distribution of HIP and partly that of the major cytoplasmic chaperones,
HSP70 and HSP90, reflecting a direct molecular interaction with both chaperones. 相似文献
78.
79.
Sexual reproduction,sporophyte development and molecular variation in the model moss Physcomitrella patens: introducing the ecotype Reute 下载免费PDF全文
80.
Gene expression changes in male accessory glands during ageing are accompanied by reproductive decline in Drosophila melanogaster 下载免费PDF全文
Senescence is accompanied by loss of reproductive functions. Here, we studied reproductive ageing in Drosophila melanogaster males and asked whether the expected decline in male reproductive success is due to diminished functionality of the male accessory gland (AG). The male AG produces the majority of seminal fluid proteins (SFPs) transferred to the female at mating. SFPs induce female postmating changes and are key to male reproductive success. We measured age‐dependent gene expression changes for five representative SFP genes in males from four different age groups ranging from 1 to 6 weeks after eclosion. Simultaneously, we also measured male reproductive success in postmating traits mediated by transfer of these five SFPs. We found a decreased in male SFP gene expression with advancing age and an accompanying decline in male postmating success. Hence, male reproductive senescence is associated with a decline in functionality of the male AG. While overall individual SFP genes decreased in expression, our results point towards the idea that the composition of an ejaculate might change with male age as the rate of change was variable for those five genes. 相似文献