Mutations in Ovis aries TMEM154 are associated with lower small ruminant lentivirus proviral concentration in one sheep flock

Small ruminant lentivirus (SRLV), also called ovine progressive pneumonia virus or maedi‐visna, is present in 24% of US sheep. Like human immunodeficiency virus, SRLV is a macrophage‐tropic lentivirus that causes lifelong infection. The production impacts from SRLV are due to a range of disease symptoms, including pneumonia, arthritis, mastitis, body condition wasting and encephalitis. There is no cure and no effective vaccine for preventing SRLV infection. However, breed differences in prevalence and proviral concentration indicate a genetic basis for susceptibility to SRLV. Animals with high blood proviral concentration show increased tissue lesion severity, so proviral concentration represents a live animal test for control post‐infection in terms of proviral replication and disease severity. Recently, it was found that sheep with two copies of TMEM154 haplotype 1 (encoding lysine at position 35) had lower odds of SRLV infection. In this study, we examined the relationship between SRLV control post‐infection and variants in two genes, TMEM154 and CCR5, in four flocks containing 1403 SRLV‐positive sheep. We found two copies of TMEM154 haplotype 1 were associated with lower SRLV proviral concentration in one flock (P < 0.02). This identified the same favorable diplotype for SRLV control post‐infection as for odds of infection. However, frequencies of haplotypes 2 and 3 were too low in the other three flocks to test. The CCR5 promoter deletion did not have consistent association with SRLV proviral concentration. Future work in flocks with more balanced allele frequencies is needed to confirm or refute TMEM154 association with control of SRLV post‐infection.     

Calcium concentration in leaf litter affects the abundance and survival of crustaceans in streams draining warm–temperate forests

相似文献   

TMEM207 hinders the tumour suppressor function of WWOX in oral squamous cell carcinoma

The WW domain‐containing oxidoreductase (WWOX) functions as a tumour suppressor in oral carcinogenesis. As aberrant TMEM207 expression may lead to tumour progression by hampering the tumour suppressor function of WWOX in various cancers, we explored the expression and pathobiological properties of TMEM207, focusing on the WWOX‐mediated regulation of the HIF‐1α pathway in oral squamous cell carcinoma (OSCC). TMEM207 immunoreactivity was detected in 40 of 90 OSCC samples but not in neighbouring non‐tumorous epithelial tissues. Moreover, TMEM207 expression was significantly correlated with lymph node metastasis and poor prognosis. An in situ proximal ligation assay demonstrated the colocalization of TMEM207 and WWOX in invasive OSCC cells, especially glycogen‐rich ones. Enforced expression of TMEM207 abrogated the binding of WWOX to HIF‐1α, increased HIF‐1α and GLUT‐1 expression, even under normoxic conditions, and promoted tumour growth in a xenoplant assay using SAS tongue squamous cancer cells. In contrast, TMEM207 knockdown decreased GLUT‐1 expression in two OSCC cell lines. As a whole, our findings indicate that the aberrant expression of TMEM207 contributes to tumour progression in OSCC, possibly via promoting aerobic glycolysis.     

Contrasting calcium localization and speciation in leaves of the Medicago truncatula mutant cod5 analyzed via synchrotron X–ray techniques

Oxalate‐producing plants accumulate calcium oxalate crystals (CaOx_(c)) in the range of 3–80% w/w of their dry weight, reducing calcium (Ca) bioavailability. The calcium oxalate deficient 5 (cod5) mutant of Medicago truncatula has been previously shown to contain similar Ca concentrations to wild‐type (WT) plants, but lower oxalate and CaOx_(c) concentrations. We imaged the Ca distribution in WT and cod5 leaflets via synchrotron X–ray fluorescence mapping (SXRF). We observed a difference in the Ca distribution between cod5 and WT leaflets, manifested as an abundance of Ca in the interveinal areas and a lack of Ca along the secondary veins in cod5, i.e. the opposite of what is observed in WT. X–ray microdiffraction (μXRD) of M. truncatula leaves confirmed that crystalline CaOx_(c) (whewellite; CaC₂O₄·H₂O) was present in the WT only, in cells sheathing the secondary veins. Together with μXRD, microbeam Ca K–edge X–ray absorption near‐edge structure spectroscopy (μXANES) indicated that, among the forms of CaOx, i.e. crystalline or amorphous, only amorphous CaOx was present in cod5. These results demonstrate that deletion of COD5 changes both Ca localization and the form of CaOx within leaflets.     

Developing a biocontrol strategy to protect stored potato tubers from infestation with potato tuber moth species in the Andean region

Heavy infestations of stored potato (Solanum tuberosum L.) tubers by the two potato tuber moth species Symmetrischema tangolias (Gyen) and Tecia solanivora (Povolny) frequently occur in Andean potato‐growing regions of Ecuador. The aim of the study was to develop a biological control strategy for both species using powder formulations made of inert substances, Phthorimaea operculella (Zeller) granulovirus (PhopGV) and Bacillus thuringiensis Berliner subsp. kurstaki (Btk). The LC₅₀ of PhopGV on T. solanivora was 0.33 LE/L, and Btk caused 82.7% mortality at a concentration of 100 g/L in bioassays. The efficacy of talcum, kaolin, calcium carbonate and sand ranged between 76.2% and 98.7%. Calcium carbonate was highly effective to control both species; however, its efficacy was affected by the relative humidity and dropped to 55.4% at relative humidity of 100%. PhopGV at concentrations of five larvae equivalents (LE) per kg kaolin and Btk at a concentration of 60 g Btk/kg talcum caused 95.7% and 88.1% mortality of T. solanivora, respectively. In storage experiments, the efficacy of calcium carbonate alone and in combination with PhopGV (20 LE/kg) and Btk (15 g/kg) caused 95.0–99.8% mortality of T. solanivora in all treatments and reduced infestation on potato tubers by 83.6%–91.0%. In the case of S. tangolias, Btk significantly increased mortality to 96.5% compared with calcium carbonate alone and reduced tuber infestation by 83.4%. Storage of potato tubers in thin layers enhanced the efficacy of the calcium carbonate treatment compared with storage in bags. It was concluded that calcium carbonate alone seems to be appropriate for the control of T. solanivora, and an addition of 15 g Btk/kg would improve the control of S. tangolias. It is suggested to test these new formulations under on‐farm storage conditions.     

The Lactoperoxidase System: a Natural Biochemical Biocontrol Agent for Pre‐ and Postharvest Applications

Controlling pests in pre‐ and postharvest crops using natural and low‐impact products is a major challenge. The lactoperoxidase system is an enzymatic system that exists in all external secretions in mammals and is part of the non‐immune system. We tested its efficacy in in vitro microplates on Phytophthora infestans, Penicillium digitatum, Penicillium italicum, Penicillium expansum and Botrytis cinerea to determine the most suitable concentrations for use. Then, we verified its efficacy in planta under controlled conditions. Solutions prepared with 5.4 mm iodide and 1.2 mm thiocyanate and diluted threefold inhibited pathogen growth in vitro by 63–100%. Twofold‐diluted solutions protected potato plants against P. infestans by 60–74% under controlled conditions. Undiluted solution inhibited orange's and apple's postharvest pathogens in curative application with efficacy levels ranging between 84 and 95% in orange and between 63 and 74% in apple. 1.5‐fold concentrated solutions inhibited postharvest pathogens of apple in curative application with efficacy levels ranging between 84 and 92%. Our results also show that the oxidative stress response of fruit following wounding could interfere with ion efficiency. Our tests demonstrate for the first time that this biochemical method is as efficient as a conventional synthetic chemical method under controlled conditions.     

The V2 receptor antagonist tolvaptan raises cytosolic calcium and prevents AQP2 trafficking and function: an in vitro and in vivo assessment

Tolvaptan, a selective vasopressin V2 receptor antagonist, is a new generation diuretic. Its clinical efficacy is in principle due to impaired vasopressin‐regulated water reabsorption via aquaporin‐2 (AQP2). Nevertheless, no direct in vitro evidence that tolvaptan prevents AQP2‐mediated water transport, nor that this pathway is targeted in vivo in patients with syndrome of inappropriate antidiuresis (SIAD) has been provided. The effects of tolvaptan on the vasopressin–cAMP/PKA signalling cascade were investigated in MDCK cells expressing endogenous V2R and in mouse kidney. In MDCK, tolvaptan prevented dDAVP‐induced increase in ser256‐AQP2 and osmotic water permeability. A similar effect on ser256‐AQP2 was found in V1aR ?/? mice, thus confirming the V2R selectively. Of note, calcium calibration in MDCK showed that tolvaptan per se caused calcium mobilization from the endoplasmic reticulum resulting in a significant increase in basal intracellular calcium. This effect was only observed in cells expressing the V2R, indicating that it requires the tolvaptan–V2R interaction. Consistent with this finding, tolvaptan partially reduced the increase in ser256‐AQP2 and the water permeability in response to forskolin, a direct activator of adenylyl cyclase (AC), suggesting that the increase in intracellular calcium is associated with an inhibition of the calcium‐inhibitable AC type VI. Furthermore, tolvaptan treatment reduced AQP2 excretion in two SIAD patients and normalized plasma sodium concentration. These data represent the first detailed demonstration of the central role of AQP2 blockade in the aquaretic effect of tolvaptan and underscore a novel effect in raising intracellular calcium that can be of significant clinical relevance.     

Arabidopsis PLC2 is involved in auxin‐modulated reproductive development

Phospholipase C (PLC) is an enzyme that plays crucial roles in various signal transduction pathways in mammalian cells. However, the role of PLC in plant development is poorly understood. Here we report involvement of PLC2 in auxin‐mediated reproductive development in Arabidopsis. Disruption of PLC2 led to sterility, indicating a significant role for PLC2 in reproductive development. Development of both male and female gametophytes was severely perturbed in plc2 mutants. Moreover, elevated auxin levels were observed in plc2 floral tissues, suggesting that the infertility of plc2 plants may be associated with increased auxin concentrations in the reproductive organs. We show that expression levels of the auxin reporters DR5:GUS and DR5:GFP were elevated in plc2 anthers and ovules. In addition, we found that expression of the auxin biosynthetic YUCCA genes was increased in plc2 plants. We conclude that PLC2 is involved in auxin biosynthesis and signaling, thus modulating development of both male and female gametophytes in Arabidopsis.     

Deletion variant near ZNF389 is associated with control of ovine lentivirus in multiple sheep flocks

Ovine lentivirus (OvLV) is a macrophage‐tropic lentivirus found in many countries that causes interstitial pneumonia, mastitis, arthritis and cachexia in sheep. There is no preventive vaccine and no cure, but breed differences suggest marker‐assisted selective breeding might improve odds of infection and control of OvLV post‐infection. Although variants in TMEM154 have consistent association with odds of infection, no variant in any gene has been associated with host control of OvLV post‐infection in multiple animal sets. Proviral concentration is a live‐animal diagnostic measure of OvLV control post‐infection related to severity of OvLV‐induced lesions. A recent genome‐wide association study identified a region including four zinc finger genes associated with proviral concentration in one Rambouillet flock. To refine this region, we tested additional variants and identified a small insertion/deletion variant near ZNF389 that showed consistent association with proviral concentration in three animal sets (P < 0.05). These animal sets contained Rambouillet, Polypay and crossbred sheep from multiple locations and management conditions. Strikingly, one flock had exceptionally high prevalence (>87%, including yearlings) and mean proviral concentration (>950 copies/μg), possibly due to needle sharing. The best estimate of proviral concentration by genotype, obtained from all 1310 OvLV‐positive animals tested, showed insertion homozygotes had less than half the proviral concentration of other genotypes (P < 0.0001). Future work will test additional breeds, management conditions and viral subtypes, and identify functional properties of the haplotype this deletion variant tracks. To our knowledge, this is the first genetic variant consistently associated with host control of OvLV post‐infection in multiple sheep flocks.     

Invasive submerged freshwater macrophytes are more plastic in their response to light intensity than to the availability of free CO2 in air‐equilibrated water

相似文献   

Co‐expression of mouse TMEM63A,TMEM63B and TMEM63C confers hyperosmolarity activated ion currents in HEK293 cells

Osmoreception is essential for systemic osmoregulation, a process to stabilize the tonicity and volume of the extracellular fluid through regulating the ingestive behaviour, sympathetic outflow and renal function. The sensation of osmotic changes by osmoreceptor neurons is mediated by ion channels that detect the change of osmolarity in extracellular fluid. However, the molecular identity of these channels remains mysterious. AtCSC1and OSCA1,two closely related paralogues from Arabidopsis, have been demonstrated to form hyperosmolarity activated ion channels, which makes their mammalian orthologues—the members of TMEM63 proteins, possible candidates for osmoreceptor transduction channel. To test this possibility, we cloned the cDNAs of all the three members of the mouse TMEM63 family, TMEM63A, TMEM63B and TMEM63C from the mRNA from mouse brain. When all of the three subtypes of TMEM63 proteins were co‐expressed in HEK293 cells, we recorded membrane currents evoked by hypertonic stimulation in these cells. However, the cells expressing the combinations of any two subtypes of TMEM63 proteins could not exhibit any hyperosmolarity evoked currents. Thus, all the three members of TMEM63 proteins are required to constitute a hyperosmolarity activated ion channel. We propose that the TMEM63 proteins may serve as an osmolarity sensitive ion channel for the osmoreception. Copyright © 2016 John Wiley & Sons, Ltd.     

白念珠菌CaGDT1基因的功能研究

人类跨膜蛋白TMEM165与酿酒酵母Sc Gdt1均属于阳离子/钙离子交换器家族的成员,在本研究中,通过序列比对在白念珠菌中发现了Sc GDT1的同源基因Ca GDT1,表型互补实验显示Ca GDT1基因的表达能够抑制Sc GDT1基因缺失所造成的钙离子敏感性,证明Ca GDT1是Sc GDT1的同功基因。此外,通过同源重组原理敲除了Ca GDT1的2个等位基因。表型筛选结果表明gdt1/gdt1缺失株对钙离子、细胞壁和内质网3种胁迫均不敏感,而对酮康唑和特比萘芬2种抗真菌药物具有耐受性。     

Common genetic variants in GAL,GAP43 and NRSN1 and interaction networks confer susceptibility to Hirschsprung disease

Hirschsprung disease (HSCR) is a severe multifactorial genetic disorder. Microarray studies indicated GAL, GAP43 and NRSN1 might contribute to the altered risk in HSCR. Thus, we focused on genetic variations in GAL, GAP43 and NRSN1, and the gene‐gene interactions involved in HSCR susceptibility. We recruited a strategy combining case‐control study and MassArray system with interaction network analysis. For GAL, GAP43 and NRSN1, a total of 18 polymorphisms were assessed in 104 subjects with sporadic HSCR and 151 controls of Han Chinese origin. We found statistically significant differences between HSCR and control groups at 5 genetic variants. For each gene, the haplotypes combining all polymorphisms were the most significant. Based on SNPsyn, MDR and GeneMANIA analyses, we observed significant gene‐gene interactions among GAL, GAP43, NRSN1 and our previous identified RELN, GABRG2 and PTCH1. Our study for the first time indicates that genetic variants within GAL, GAP43 and NRSN1 and related gene‐gene interaction networks might be involved in the altered susceptibility to HSCR in the Han Chinese population, which might shed more light on HSCR pathogenesis.     

Candidate gene polymorphisms for behavioural adaptations during urbanization in blackbirds

Successful urban colonization by formerly rural species represents an ideal situation in which to study adaptation to novel environments. We address this issue using candidate genes for behavioural traits that are expected to play a role in such colonization events. We identified and genotyped 16 polymorphisms in candidate genes for circadian rhythms, harm avoidance and migratory and exploratory behaviour in 12 paired urban and rural populations of the blackbird Turdus merula across the Western Palaearctic. An exonic microsatellite in the SERT gene, a candidate gene for harm avoidance behaviour, exhibited a highly significant association with habitat type in an analysis conducted across all populations. Genetic divergence at this locus was consistent in 10 of the 12 population pairs; this contrasts with previously reported stochastic genetic divergence between these populations at random markers. Our results indicate that behavioural traits related to harm avoidance and associated with the SERT polymorphism experience selection pressures during most blackbird urbanization events. These events thus appear to be influenced by homogeneous adaptive processes in addition to previously reported demographic founder events.     

Validation of genetic polymorphisms on BTA14 associated with carcass trait in a commercial Hanwoo population

The objective of this study was to validate the association of significant SNPs identified from a previous genome‐wide association study with carcass weight (CWT) in a commercial Hanwoo population. We genotyped 13 SNPs located on BTA14 in 867 steers from Korea Hanwoo feedlot bulls. Of these 13 SNPs, five SNPs, namely rs29021868, rs110061498, rs109546980, rs42404006 and rs42303720, were found to be significantly associated (P < 0.001) with CWT. These five significant markers spanned the 24.3 to 29.4 Mb region of BTA14. The most significant marker (rs29021868) for CWT in this study had a 13.07 kg allele substitution effect and accounted for 2.4% of the additive genetic variance in the commercial Hanwoo population. The SNP marker rs109546980 was found to be significantly associated with both CWT (P < 0.001) and eye muscle area (P < 0.001) and could potentially be exploited for marker‐assisted selection in Hanwoo cattle. We also genotyped the ss319607402 variation, which maps to intron2 of PLAG1 gene and which is already reported to be associated with height, to identify any significant association with carcass weight; however, no such association was observed in this Hanwoo commercial population.     

Leaf and Soil Nutrients in a Chronosequence of Second‐Growth Forest in Central Amazonia: Implications for Restoration of Abandoned Lands

Subsistence agriculture, cattle ranching, and periodical land abandonment are common land‐use practices in Amazonia. Because changes in land use affect biogeochemical cycles, secondary forests growing after land abandonment develop at varying speeds and spatial patterns, due in part to varying nutrient dynamics. Leaf and soil nutrient concentrations can provide useful information on nutrient cycling processes and strategies of nutrient use by trees that are suitable for introduction to abandoned areas. To understand nutrient dynamics in secondary forests from different regeneration stages, as well as the importance of pioneer species in the regeneration process, we measured the concentration of macronutrients in leaves of three pioneer tree species (Vismia cayennensis, Cecropia sciadophylla, and Bellucia dichotoma) in central Amazon secondary forests. We also measured macronutrients in the topsoil under the trees. We found that type of prior land use, time since abandonment, and number of fire events were significantly correlated with the concentrations of leaf and soil macronutrients, explaining between 10 and 38% of the variation in macronutrient concentrations. The observed patterns suggest that management practices affect the processes involved in N cycling and availability. Of the three pioneer species, C. sciadophylla showed the highest nutrient resorption efficiency and the highest leaf nutritional quality. We suggest that these two features determine a higher potential of C. sciadophylla for natural regeneration and restoration of abandoned lands.     

Daphnia predation on the amphibian chytrid fungus and its impacts on disease risk in tadpoles

Direct predation upon parasites has the potential to reduce infection in host populations. For example, the fungal parasite of amphibians, Batrachochytrium dendrobatidis (Bd), is commonly transmitted through a free‐swimming zoospore stage that may be vulnerable to predation. Potential predators of Bd include freshwater zooplankton that graze on organisms in the water column. We tested the ability of two species of freshwater crustacean (Daphnia magna and D. dentifera) to consume Bd and to reduce Bd density in water and infection in tadpoles. In a series of laboratory experiments, we allowed Daphnia to graze in water containing Bd while manipulating Daphnia densities, Daphnia species identity, grazing periods and concentrations of suspended algae (Ankistrodesmus falcatus). We then exposed tadpoles to the grazed water. We found that high densities of D. magna reduced the amount of Bd detected in water, leading to a reduction in the proportion of tadpoles that became infected. Daphnia dentifera, a smaller species of Daphnia, also reduced Bd in water samples, but did not have an effect on tadpole infection. We also found that algae affected Bd in complex ways. When Daphnia were absent, less Bd was detected in water and tadpole samples when concentrations of algae were higher, indicating a direct negative effect of algae on Bd. When Daphnia were present, however, the amount of Bd detected in water samples showed the opposite trend, with less Bd when densities of algae were lower. Our results indicate that Daphnia can reduce Bd levels in water and infection in tadpoles, but these effects vary with species, algal concentration, and Daphnia density. Therefore, the ability of predators to consume parasites and reduce infection is likely to vary depending on ecological context.     

Effects of prohydrojasmon‐treated corn plants on attractiveness to parasitoids and the performance of their hosts

We investigated the effect of prohydrojasmon [propyl (1RS,2RS)‐(3‐oxo‐ 2‐pentylcyclopentyl) acetate] (PDJ) treatment of intact corn plants, on their attractiveness to the specialist endoparasitoid, Cotesia kariyai Watanabe (Hymenoptera: Braconidae), and on the performance of the common armyworm, Mythimna separata (Walker) (Lepidoptera: Noctuidae) under laboratory conditions. Attractiveness of C. kariyai to PDJ‐treated plants was studied in a wind tunnel, whereas performance of M. separata larvae was tested in plastic cages. The attractiveness of the treated plants increased with concentrations of PDJ increasing to 2 mm , which was equivalent to the attractiveness of host‐infested plants. PDJ‐treated corn plants emitted 16 volatile compounds (α‐pinene, β‐myrcene, (Z)‐3‐hexenyl acetate, limonene, (E)‐β‐ocimene, linalool, (E)‐4,8‐dimethyl‐1,3,7‐nonatriene, (+)‐cyclosativene, ylangene, (E)‐β‐farnesene, (E, E)‐4,8,12‐trimethyl‐1,3,7,11‐tridecatetraene, α‐bergamotene, γ‐cadinene, δ‐cadinene, α‐muulolene and nerolidol), most of which were observed in the headspace of host‐infested corn plants with some quantitative and qualitative differences. We also tested the effects of PDJ treatment on the performance of M. separata larvae. The survival rates of the larval and pupal stages were significantly lower at 2 mm level of PDJ. A significant decrease in weight at 6th stadium larvae was observed only at 2 mm level of PDJ. In contrast, PDJ treatment at all PDJ concentration levels caused significant reduction in weight of pupal stage as compared to control. These data suggested that PDJ, originally developed as a plant growth regulator, especially to induce coloring of fruits, has the potential to induce direct and indirect defenses in corn plants against common armyworm, M. separata.     

Environmental DNA analysis for estimating the abundance and biomass of stream fish

相似文献