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151.
152.
Long noncoding RNAs (lncRNAs) display essential roles in cancer progression. FLVCR1-AS1 is a rarely investigated lncRNAs involved in various human cancers, such as hepatocellular carcinoma and lung cancer. However, its function in glioma has not been clarified. In our study, we found that FLVCR1-AS1 was highly expressed in glioma tissues and cell lines. And upregulation of FLVCR1-AS1 predicted poor prognosis in patients with glioma. Moreover, FLVCR1-AS1 knockdown inhibited proliferation, migration and invasion of glioma cells. Through bioinformatics analysis, we identified that FLVCR1-AS1 was a sponge for miR-4731-5p to upregulate E2F2 expression. Moreover, rescue assays indicated that FLVCR1-AS1 modulated E2F2 expression to participate in glioma progression. Altogether, our research demonstrates that the FLVCR1-AS1/miR-4731-5p/E2F2 axis is a novel signaling in glioma and may be a potential target for tumor therapy.  相似文献   
153.

Background

Hereditary optic neuropathies (HONs) are a heterogeneous group of disorders that affect retinal ganglion cells (RGCs) and axons that form the optic nerve. Leber's Hereditary Optic Neuropathy and the autosomal dominant optic atrophy related to OPA1 mutations are the most common forms. Nonsyndromic autosomal recessive optic neuropathies are rare and their existence has been long debated. We recently identified the first gene responsible for these conditions, TMEM126A. This gene is highly expressed in retinal cellular compartments enriched in mitochondria and supposed to encode a mitochondrial transmembrane protein of unknown function.

Methods

A specific polyclonal antibody targeting the TMEM126A protein has been generated. Quantitative fluorescent in situ hybridization, cellular fractionation, mitochondrial membrane association study, mitochondrial sub compartmentalization analysis by both proteolysis assays and transmission electron microscopy, and expression analysis of truncated TMEM126A constructs by immunofluorescence confocal microscopy were carried out.

Results

TMEM126A mRNAs are strongly enriched in the vicinity of mitochondria and encode an inner mitochondrial membrane associated cristae protein. Moreover, the second transmembrane domain of TMEM126A is required for its mitochondrial localization.

Conclusions

TMEM126A is a mitochondrial located mRNA (MLR) that may be translated in the mitochondrial surface and the protein is subsequently imported to the inner membrane. These data constitute the first step toward a better understanding of the mechanism of action of TMEM126A in RGCs and support the importance of mitochondrial dysfunction in the pathogenesis of HON.

General significance

Local translation of nuclearly encoded mitochondrial mRNAs might be a mechanism for rapid onsite supply of mitochondrial membrane proteins.  相似文献   
154.
About 70 Streptomyces species, isolated from soils of greenhouses and citrus orchards were evaluated for their antagonistic activity against Verticillium dahliae, Fusarium subglutinans, Fusarium sambucinum, Phoma glomerata and Nattrassia mangiferae. Preliminary screening for antimicrobial activity was determined by dual culture method. The soils of Kerman are rich sources of micro-organisms with potent biological activities, and screening programmes are to be conducted to reveal the presence of active Actinomycetes isolates against phytopathogenic fungi.  相似文献   
155.

The bacterial symbionts isolated from the entomopathogenic nematodes were compared for their pathogenicity to last instar larvae of G. mellonella at both Phases I and II. Most bacterial symbionts at Phase I cause 100% mortality within 2-3 days post-injection with 1 times; 10 3 cells/larva. The pathogenicity of Phase I decreased in the following order: Xenorhabdus nematopbilus, Flavimonas oryzihabitans, Photorhabdus luminescens and Xenorhabdus bovienii with LD 50 values of 40, 55, 70 and 170 cells/larva. The injection of Phase II of the bacterial symbionts did not give 100% mortality even after 4 days post-injection. The time mortality response of G. mellonella larvae to both phases of the bacterial symbiont was significantly different usually at the two highest concentrations tested. The significancy in case of Phase I was in the following order from lowest to highest, F . oryzihabitans , X . nematophilus , P. luminescens and X. bovienii . It was 20.57, 23.96, 23.99 and 53.76 h, respectively. Also, F. oryzihabitans gave the lowest LT 50 value for its Phase II form. It was 36.85 h, and this is followed by X. bovienii , X. nematophilus , and P. luminescens , the LT 50 values of which were 69.29, 74.08 and 74.49 h, respectively. The results suggest that there is a direct correlation between toxin concentration and rate of killing the larvae. On the other hand, there is an inverse correlation between the LT 50 values and the injected concentration.  相似文献   
156.
Termites from the genus Odontotermes are known to contain numerous species complexes that are difficult to tell apart morphologically or with mitochondrial DNA sequences. We developed markers for one such cryptic species complex, that is, Odontotermes srinakarinensis sp. nov. from Maxwell Hill Forest Reserve (Perak, Malaysia), and characterised them using a sample of 41 termite workers from three voucher samples from the same area. We then genotyped 150 termite individuals from 23 voucher samples/colonies of this species complex from several sites in Peninsular Malaysia. We analysed their population by constructing dendograms from the proportion of shared-alleles between individuals and genetic distances between colonies; additionally, we examined the Bayesian clustering pattern of their genotype data. All methods of analysis indicated that there were two distinct clusters within our data set. After the morphologies of specimens from each cluster were reexamined, we were able to separate the two species morphologically and found that a single diagnostic character found on the mandibles of its soldiers could be used to separate the two species quite accurately. The additional species in the clade was identified as Odontotermes denticulatus after it was matched to type specimens at the NHM London and Cambridge Museum of Zoology.  相似文献   
157.
158.
Hemocyanins are multimeric copper-containing hemolymph proteins involved in oxygen binding and transport in all major arthropod lineages. Most arachnids have seven primary subunits (encoded by paralogous genes ag), which combine to form a 24-mer (4 × 6) quaternary structure. Within some spider lineages, however, hemocyanin evolution has been a dynamic process with extensive paralog duplication and loss. We have obtained hemocyanin gene sequences from numerous representatives of the spider infraorders Mygalomorphae and Araneomorphae in order to infer the evolution of the hemocyanin gene family and estimate spider relationships using these conserved loci. Our hemocyanin gene tree is largely consistent with the previous hypotheses of paralog relationships based on immunological studies, but reveals some discrepancies in which paralog types have been lost or duplicated in specific spider lineages. Analyses of concatenated hemocyanin sequences resolved deep nodes in the spider phylogeny and recovered a number of clades that are supported by other molecular studies, particularly for mygalomorph taxa. The concatenated data set is also used to estimate dates of higher-level spider divergences and suggests that the diversification of extant mygalomorphs preceded that of extant araneomorphs. Spiders are diverse in behavior and respiratory morphology, and our results are beneficial for comparative analyses of spider respiration. Lastly, the conserved hemocyanin sequences allow for the inference of spider relationships and ancient divergence dates.  相似文献   
159.
《Anthrozo?s》2013,26(1):25-42
Abstract

A conceptual model was developed to describe the dynamics of the pet dog population. The model synthesizes existing data collected for a variety of purposes to estimate the size of the various components of the pet dog population in Washington and Iowa during 1991. The total population mortality rate was estimated as 12.4% per year. Animal shelters in Washington and Iowa handled 7.6% and euthanized 4.0% of the dog population in those two states. When these estimates were extrapolated to the entire U.S. dog population, the model predicted that the total annual turnover in owned dogs was 14.7%, or 7.71 million dogs, that 4 million dogs were handled by animal shelters, and that 2.1 million were euthanized. It was also estimated that 79% of all female dogs were spayed, that household breeding could be attributed to less than one-fifth (18.7%) of the female dogs in the reproductive pool, and that the number of owners contributing to total dog population turnover through failure to retain their dog (103,453) was approximately three times the number of owners who allowed their female dogs to be bred (32,513).  相似文献   
160.
Abstract

The influence of base composition (and sequence) on the process of interaction between synthetic polynucleotides and spermine, has been investigated using ultraviolet (including second derivative) spectroscopy, and electric dichroism.

Different binding modes of spermine to poly(dG-dC) as compared to A-T containing polynucleotides, were evidenced. An interaction with the N7 and 06 of guanine is probably partially involved in the former case while simple electrostatic interaction with the phosphate groups would dominate in the latter.

In the intermediate binding range (spermine over DNA phosphate molar ratios Sp/P of the order of 0.1 to 0.2), the complexes with poly(dA) · poly(dT) and those with poly(dA-dT) displayed an important contribution of a permanent dipole moment to the orientation mechanism, as detected by the application of bipolar pulses in electric dichroism experiments. Just prior to precipitation (at Sp/P slightly larger than 0.3), these polynucleotides show electric dichroism and relaxation times characteristics corresponding to toroidal particles formation resulting from a bending of their chains. This implies asymmetric binding to phosphate sites on A-T containing polynucleotides. At low Sp/P ratios, spermine induced a stiffening of poly (dG-dC). No influence of spermine on the orientation mechanism of this polynucleotide was detected for Sp/P values ranging from zero to 0.35. The spermine-induced bending of A-T rich regions thus appears to be essential for DNA condensation into toroidal particles.  相似文献   
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