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991.
Sarah E. Antinone Ghanashyam D. Ghadge Tukiet T. Lam Lijun Wang Raymond P. Roos William N. Green 《The Journal of biological chemistry》2013,288(30):21606-21617
Mutations in Cu,Zn-superoxide dismutase (mtSOD1) cause familial amyotrophic lateral sclerosis (FALS), a neurodegenerative disease resulting from motor neuron degeneration. Here, we demonstrate that wild type SOD1 (wtSOD1) undergoes palmitoylation, a reversible post-translational modification that can regulate protein structure, function, and localization. SOD1 palmitoylation was confirmed by multiple techniques, including acyl-biotin exchange, click chemistry, cysteine mutagenesis, and mass spectrometry. Mass spectrometry and cysteine mutagenesis demonstrated that cysteine residue 6 was the primary site of palmitoylation. The palmitoylation of FALS-linked mtSOD1s (A4V and G93A) was significantly increased relative to that of wtSOD1 expressed in HEK cells and a motor neuron cell line. The palmitoylation of FALS-linked mtSOD1s (G93A and G85R) was also increased relative to that of wtSOD1 when assayed from transgenic mouse spinal cords. We found that the level of SOD1 palmitoylation correlated with the level of membrane-associated SOD1, suggesting a role for palmitoylation in targeting SOD1 to membranes. We further observed that palmitoylation occurred predominantly on disulfide-reduced as opposed to disulfide-bonded SOD1, suggesting that immature SOD1 is the primarily palmitoylated species. Increases in SOD1 disulfide bonding and maturation with increased copper chaperone for SOD1 expression caused a decrease in wtSOD1 palmitoylation. Copper chaperone for SOD1 overexpression decreased A4V palmitoylation less than wtSOD1 and had little effect on G93A mtSOD1 palmitoylation. These findings suggest that SOD1 palmitoylation occurs prior to disulfide bonding during SOD1 maturation and that palmitoylation is increased when disulfide bonding is delayed or decreased as observed for several mtSOD1s. 相似文献
992.
993.
994.
William T. Burke 《Ocean Development & International Law》2013,44(3):273-314
Abstract The 1982 Convention on the Law of the Sea provides for coastal state sovereign rights over all living resources within the exclusive economic zone, but in a separate article makes special provision for so‐called highly migratory species (HMS) that are specifically identified in an Annex to the treaty. This paper examines the basic treaty provisions concerning all fisheries in the EEZ, highlighting the position of HMS, and then devotes detailed consideration to the regulation of fishing for HMS in light of Article 64 and other articles of the treaty. Discussion centers upon the requirements of Article 64, including the duty of cooperation and its subject matter, the meaning and consequence of failure to cooperate, the manner of cooperation under Article 64, and the application of the treaty to enclaves of high seas. Attention is given to the application to HMS of specific obligations under Articles 61 and 62, authority over HMS fishing within archipelagic waters, and the use of fish aggregation devices. There is also consideration of the relationship between the 1982 Convention and customary law regarding HMS, with particular attention to the position vis‐a‐vis the Convention of the United States as a nonsignatory who does not recognize coastal state jurisdiction over tuna but claims sovereign rights over all other highly migratory species within its recently proclaimed exclusive economic zone. 相似文献
995.
William E. Schrank Blanca Skoda Paul Parsons Noel Roy 《Ocean Development & International Law》2013,44(4):357-390
The commercial fishery for northern cod off Newfoundland has been closed since 1992. Since then, the recreational “food fishery”; has also been closed, as have the fisheries for many additional cod and other groundfish stocks. The Newfoundland fisheries had been commercially unviable for many years before the closures. This article records the federal and provincial governments’ financial outlays (expenditures, transfer payments to individuals, subsidies, net equity purchases, and net loans) on the fishery during the decade following 1981. Special emphasis is placed on the cost of the financial restructuring of the industry in the mid‐1980s, net unemployment insurance payments, and social overhead capital expenditures. 相似文献
996.
Yasmin Rubio-Palis Mariapia Bevilacqua Domingo Alberto Medina Jorge Ernesto Moreno Lya Cárdenas Víctor Sánchez Yarys Estrada William Anaya ángela Martínez 《Memórias do Instituto Oswaldo Cruz》2013,108(2):220-228
To explore the effects of deforestation and resulting differences in vegetation and land cover on entomological parameters, such as anopheline species composition, abundance, biting rate, parity and entomological inoculation rate (EIR), three villages were selected in the Lower Caura River Basin, state of Bolívar, Venezuela. All-night mosquito collections were conducted between March 2008-January 2009 using CDC light traps and Mosquito Magnet(r) Liberty Plus. Human landing catches were performed between 06:00 pm-10:00 pm, when anophelines were most active. Four types of vegetation were identified. The Annual Parasite Index was not correlated with the type of vegetation. The least abundantly forested village had the highest anopheline abundance, biting rate and species diversity. Anopheles darlingi and Anopheles nuneztovari were the most abundant species and were collected in all three villages. Both species showed unique biting cycles. The more abundantly forested village of El Palmar reported the highest EIR. The results confirmed previous observations that the impacts of deforestation and resulting changes in vegetation cover on malaria transmission are complex and vary locally. 相似文献
997.
Richard Atherton Darlene Bhavnani Manuel Calvopi?a Yosselin Vicu?a William Cevallos Joseph Eisenberg 《Memórias do Instituto Oswaldo Cruz》2013,108(4):512-515
The aim of this study was to determine the genetic diversity of
Giardia duodenalis present in a human population living in
a northern Ecuadorian rain forest. All Giardia positive samples
(based on an ELISA assay) were analysed using a semi-nested polymerase chain
reaction-restriction fragment length polymorphism assay that targets the
glutamate dehydrogenase (gdh) gene; those amplified were
subsequently genotyped using NlaIV and RsaI enzymes. The gdh
gene was successfully amplified in 74 of 154 ELISA positive samples; 69 of the
74 samples were subsequently genotyped. Of these 69 samples, 42 (61%) were
classified as assemblage B (26 as BIII and 16 as BIV), 22 (32%) as assemblage A
(3 as AI and 19 as AII) and five (7%) as mixed AII and BIII types. In this study
site we observe similar diversity in genotypes to other regions in Latin
America, though in contrast to some previous studies, we found similar levels of
diarrheal symptoms in those individuals infected with assemblage B compared with
those infected with assemblage A. 相似文献
998.
999.
RjpA in Rhodococcus jostii is the ortholog of a channel-forming porin, MspA. Deletion of rjpA delayed growth of R. jostii on cholate but not on cholesterol. Eventual growth on cholate involved increased expression of other porins, namely, RjpB, RjpC, and RjpD. Porins appear essential for the uptake of bile acids by mycolic acid bacteria. 相似文献
1000.
Fengqiong Liu Qing Lv William W. Du Haoran Li Xiangling Yang Danyang Liu Zhaoqun Deng Wenhua Ling Yaou Zhang Burton B. Yang 《Biochimica et Biophysica Acta (BBA)/Molecular Cell Research》2013,1833(12):3272-3285
One criterion for microRNA identification is based on their conservation across species, and prediction of miRNA targets by empirical approaches using computational analysis relies on the presence of conservative mRNA 3′UTR. Because most miRNA target sites identified are highly conserved across different species, it is not clear whether miRNA targeting is species-specific. To predict miRNA targeting, we aligned all available fibronectin 3′UTRs and observed significant conservation of all 20 species. Twelve miRNAs were predicted to target most fibronectin 3′UTRs, but rodent fibronectin showed potential binding sites specific for five different miRNAs. One of them, the miR-378a-5p, contained a complete matching seed-region for all rodent fibronectin, which could not be found in any other species. We designed experiments to test whether the species-specific targeting possessed biological function and found that expression of miR-378a-5p decreased cancer cell proliferation, migration, and invasion, resulting in inhibition of tumor growth. Silencing fibronectin expression produced similar effects as miR-378a-5p, while transfection with a construct targeting miR-378-5p produced opposite results. Tumor formation assay showed that enhanced expression of fibronectin in the stromal tissues as a background environment suppressed tumor growth, while increased fibronectin expression inside the tumor cells promoted tumor growth. This was likely due to the different signaling direction, either inside-out or outside-in signal. Our results demonstrated that species-specific targeting by miRNA could also exert functional effects. Thus, one layer of regulation has been added to the complex network of miRNA signaling. 相似文献