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Patricia Prade Rodrigo Diaz Marcelo D. Vitorino James P. Cuda Prem Kumar Barrett Gruber 《Biocontrol Science and Technology》2016,26(1):23-34
Schinus terebinthifolia Raddi (Anacardiaceae) (Brazilian peppertree) is one of the most serious terrestrial invasive plants in Florida. The leaf galling psyllid, Calophya latiforceps Burckhardt (Hemiptera: Calophyidae), was discovered feeding on the Brazilian peppertree in Bahia, Brazil, in 2010, and is being evaluated for release as a biological control agent. In order to understand how this candidate biological control agent affects the growth of S. terebinthifolia, we measured the effect of the psyllid on photosynthesis, leaf chlorophyll content and plant growth. Infested plants had lower photosynthesis compared to uninfested plants 30 and 45 days after gall initiation, and chlorophyll content was lower over a 70-d period. Plant height was reduced 31% and biomass 11% after three months of infestation. Results of these studies suggest that C. latiforceps will negatively affect the growth of the Brazilian peppertree if released in Florida. 相似文献
993.
Jinglan Zhang Véronik Lachance Adam Schaffner Xianting Li Anastasia Fedick Lauren E. Kaye Jun Liao Jill Rosenfeld Naomi Yachelevich Mary-Lynn Chu Wendy G. Mitchell Richard G. Boles Ellen Moran Mari Tokita Elizabeth Gorman Kaytee Bagley Wei Zhang Fan Xia Magalie Leduc Yaping Yang Christine Eng Lee-Jun Wong Raphael Schiffmann George A. Diaz Ruth Kornreich Ryan Thummel Melissa Wasserstein Zhenyu Yue Lisa Edelmann 《PLoS genetics》2016,12(4)
Genetic leukoencephalopathies (gLEs) are a group of heterogeneous disorders with white matter abnormalities affecting the central nervous system (CNS). The causative mutation in ~50% of gLEs is unknown. Using whole exome sequencing (WES), we identified homozygosity for a missense variant, VPS11: c.2536T>G (p.C846G), as the genetic cause of a leukoencephalopathy syndrome in five individuals from three unrelated Ashkenazi Jewish (AJ) families. All five patients exhibited highly concordant disease progression characterized by infantile onset leukoencephalopathy with brain white matter abnormalities, severe motor impairment, cortical blindness, intellectual disability, and seizures. The carrier frequency of the VPS11: c.2536T>G variant is 1:250 in the AJ population (n = 2,026). VPS11 protein is a core component of HOPS (homotypic fusion and protein sorting) and CORVET (class C core vacuole/endosome tethering) protein complexes involved in membrane trafficking and fusion of the lysosomes and endosomes. The cysteine 846 resides in an evolutionarily conserved cysteine-rich RING-H2 domain in carboxyl terminal regions of VPS11 proteins. Our data shows that the C846G mutation causes aberrant ubiquitination and accelerated turnover of VPS11 protein as well as compromised VPS11-VPS18 complex assembly, suggesting a loss of function in the mutant protein. Reduced VPS11 expression leads to an impaired autophagic activity in human cells. Importantly, zebrafish harboring a vps11 mutation with truncated RING-H2 domain demonstrated a significant reduction in CNS myelination following extensive neuronal death in the hindbrain and midbrain. Thus, our study reveals a defect in VPS11 as the underlying etiology for an autosomal recessive leukoencephalopathy disorder associated with a dysfunctional autophagy-lysosome trafficking pathway. 相似文献
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Low Ability of Great Tits to Discriminate Similarly Inconspicuous Edible and Inedible Prey 下载免费PDF全文
Zuzana Karlíková Petr Veselý Jana Beránková Roman Fuchs 《Ethology : formerly Zeitschrift fur Tierpsychologie》2016,122(2):180-191
Numerous studies have shown warning coloration to facilitate the discrimination of edible and inedible prey. However, inedible insect species may possess cryptic coloration as well. It has been shown that some other visual features (especially characteristic body shape) are sufficient for the recognition of some insect taxa (e.g. ladybirds, ants, wasps). We tested the ability of wild‐caught great tits (Parus major) to discriminate between the identically coloured edible (roach – Blaptica dubia) and the inedible (firebug – Pyrrhocoris apterus) as prey according to subtle peripheral visual traits (shape of legs and antennae, body posture, and means of locomotion). Both prey species were offered either simultaneously or alternately. The ability of the birds to learn was tested by means of fourteen trial repetitions in two sessions. In general, great tits were not able to learn to discriminate between firebugs and roaches by subtle shape cues alone during the two sessions. However, multivariate analysis of individual bird behaviour showed that they adopted one of three different attitudes to the presented prey. Most of the birds never attacked any or always attacked both prey. In addition, a small proportion of the birds was able to discriminate between the two prey types and attacked only roaches. Nevertheless, firebugs survived most of the attacks, which suggests that in case of chemically protected prey, the evolution of conspicuous coloration is not always the best/only option. 相似文献
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Status of Savi's pipistrelle Hypsugo savii (Chiroptera) and range expansion in Central and south‐eastern Europe: a review 下载免费PDF全文
Marcel Uhrin Ulrich Hüttmeir Marina Kipson Péter Estók Konrad Sachanowicz Szilárd Bücs Branko Karapandža Milan Paunović Primož Presetnik Andriy‐Taras Bashta Edita Maxinová Blanka Lehotská Roman Lehotský Levente Barti István Csösz Farkas Szodoray‐Paradi Imre Dombi Tamás Görföl Sándor A. Boldogh Csaba Jére Irina Pocora Petr Benda 《Mammal Review》2016,46(1):1-16
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998.
Maja Al-Beyroutiová Miroslav Sabo Patrik Sleziak Roman Dušinský Erik Birčák Pavol Hauptvogel Andrzej Kilian Miroslav Švec 《Plant Systematics and Evolution》2016,302(8):1083-1091
Till this day, there is not much known about the phylogeny of the Secale genus; therefore, in our research, we tried to shed some lights on the issue of rye (Secale genus) taxonomy. The genetic diversity and phylogenetic relationships were evaluated using 13,842 DArTseq? polymorphic markers. The model-based clustering (STRUCTURE software) separated our 84 samples into three main clusters: perennial cluster, annual cluster, and S. sylvestre cluster. The same result was obtained using Neighbour Joining tree and self-organizing maps. Secale sylvestre, S. strictum, and S. cereale are the three main species of the Secale genus. Three samples of rye are in basal positions in phylogenetic trees. These accessions share ancient morphological characters and are probably the ancestors of different lineages within Secale. Annual Secale taxa, with the exception of S. sylvestre, create one mutual taxon. We have found out that the semi-perennial taxa of S. cereale var. multicaule and S. strictum subsp. ciliatoglume are genetically closest to the annual species of S. cereale. Phylogenetic signals for semi-perennial and annual taxa are also present in S. strictum subsp. africanum. SNP-based analysis revealed that evolution of annual S. cereale has already begun in S. strictum subsp. africanum. The results showed that S. vavilovii cannot be considered as a separate species but a subspecies of S. cereale Secale cereale subsp. dighoricum is a hybrid. It is still not clear whether we can consider S. strictum subsp. strictum and S. strictum subsp. kuprijanovii as two separate species. 相似文献
999.
PTEN Overexpression Cooperates With Lithium to Reduce the Malignancy and to Increase Cell Death by Apoptosis via PI3K/Akt Suppression in Colorectal Cancer Cells 下载免费PDF全文
Wallace Martins de Araujo Bruno Kaufmann Robbs Lilian G. Bastos Waldemir F. de Souza Flávia C.B Vidal João P.B. Viola Jose A. Morgado‐Diaz 《Journal of cellular biochemistry》2016,117(2):458-469
Lithium is a well‐established non‐competitive inhibitor of glycogen synthase kinase‐3β (GSK‐3β), a kinase that is involved in several cellular processes related to cancer progression. GSK‐3β is regulated upstream by PI3K/Akt, which is negatively modulated by PTEN. The role that lithium plays in cancer is controversial because lithium can activate or inhibit survival signaling pathways depending on the cell type. In this study, we analyzed the mechanisms by which lithium can modulate events related to colorectal cancer (CRC) progression and evaluated the role that survival signaling pathways such as PI3K/Akt and PTEN play in this context. We show that the administration of lithium decreased the proliferative potential of CRC cells in a GSK‐3β‐independent manner but induced the accumulation of cells in G2/M phase. Furthermore, high doses of lithium increased apoptosis, which was accompanied by decreased proteins levels of Akt and PTEN. Then, cells that were induced to overexpress PTEN were treated with lithium; we observed that low doses of lithium strongly increased apoptosis. Additionally, PTEN overexpression reduced proliferation, but this effect was minor compared with that in cells treated with lithium alone. Furthermore, we demonstrated that PTEN overexpression and lithium treatment separately reduced cell migration, colony formation, and invasion, and these effects were enhanced when lithium treatment and PTEN overexpression were combined. In conclusion, our findings indicate that PTEN overexpression and lithium treatment cooperate to reduce the malignancy of CRC cells and highlight lithium and PTEN as potential candidates for studies to identify new therapeutic approaches for CRC treatment. J. Cell. Biochem. 117: 458–469, 2016. © 2015 Wiley Periodicals, Inc. 相似文献
1000.
Liquid‐Like Ionic Conduction in Solid Lithium and Sodium Monocarba‐closo‐Decaborates Near or at Room Temperature 下载免费PDF全文