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991.
In higher vertebrates, sulfatases belong to a conserved family of enzymes that are involved in the regulation of cell metabolism
and in developmental cell signaling. They cleave the sulfate from sulfate esters contained in hormones, proteins, and complex
macromolecules. A highly conserved cysteine in their active site is post-translationally converted into formylglycine by the
formylglycine-generating enzyme encoded by SUMF1 (sulfatase modifying factor 1). This post-translational modification activates all sulfatases. Sulfatases are extensively
glycosylated proteins and some of them follow trafficking pathways through cells, being secreted and taken up by distant cells.
Many proteoglycans, glycoproteins, and glycolipids contain sulfated carbohydrates, which are sulfatase substrates. Indeed,
sulfatases operate as decoding factors for a large amount of biological information contained in the structures of the sulfated
sugar chains that are covalently linked to proteins and lipids. Modifications to these sulfate groups have pivotal roles in
modulating specific signaling pathways and cell metabolism in mammals. 相似文献
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995.
V. Le Fourn K. Gaplovska-Kysela B. Guhl R. Santimaria C. Zuber J. Roth 《Cellular and molecular life sciences : CMLS》2009,66(8):1434-1445
Little is known about the fate of machinery proteins of the protein quality control and endoplasmic reticulum(ER)-associated
degradation (ERAD). We investigated the degradation of the ERAD component EDEM1, which directs overexpressed misfolded glycoproteins
to degradation. Endogenous EDEM1 was studied since EDEM1 overexpression not only resulted in inappropriate occurrence throughout
the ER but also caused cytotoxic effects. Proteasome inhibitors had no effect on the clearance of endogenous EDEM1 in non-starved
cells. However, EDEM1 could be detected by immunocytochemistry in autophagosomes and biochemically in LC3 immuno-purified
autophagosomes. Furthermore, influencing the lysosome-autophagy pathway by vinblastine or pepstatin A/E64d and inhibiting
autophagosome formation by 3-methyladenine or ATGs short interfering RNA knockdown stabilized EDEM1. Autophagic degradation
involved removal of cytosolic Triton X-100-insoluble deglycosylated EDEM1, but not of EDEM1-containing ER cisternae. Our studies
demonstrate that endogenous EDEM1 in cells not stressed by the expression of a transgenic misfolded protein reaches the cytosol
and is degraded by basal autophagy.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Received 15 January 2009; received after revision 16 February 2009; accepted 17 February 2009
V. Le Fourn, K. Gaplovska-Kysela: These authors equally contributed to this work. 相似文献
996.
This paper describes the design of a unified framework for a multilingual text-to-speech (TTS) synthesis engine – Crystal. The unified framework defines the common TTS modules for different languages and/or dialects. The interfaces between consecutive modules conform to the speech synthesis markup language (SSML) specification for standardization, interoperability, multilinguality, and extensibility. Detailed module divisions and implementation technologies for the unified framework are introduced, together with possible extensions for the algorithm research and evaluation of the TTS synthesis. Implementation of a mixed-language TTS system for Chinese Putonghua, Chinese Cantonese, and English demonstrates the feasibility of the proposed unified framework. 相似文献
997.
The Mexican long-tongued bat ( Choeronycteris mexicana ) is a nectar-eating species that seasonally inhabits the southwestern United States. Since 1906, fewer than 1500 individuals of C. mexicana have been documented throughout the range of the species. We conducted a field survey in Arizona and New Mexico during summer 1999 to check historically occupied areas for recurrence of C. mexicana . We observed C. mexicana occupying a majority (75%, n = 18) of visited sites. Multiple individuals were observed at many sites, including young-of-year. Choeronycteris mexicana roosted in lighted areas close to entrances within mine adits, abandoned buildings, wide rock crevices, and caves. All occupied sites in Madrean evergreen woodlands or semidesert grasslands where species of Agave were present. Most sites were located near a water source and, with the exception of a single site, near areas of riparian vegetation. Sites at which we did not encounter C. mexicana were frequently disturbed, difficult to search, or historically occupied by single individuals. Based on the relatively high rate of bat recurrence, we do not believe that populations of C. mexicana in the region have declined dramatically over the past several decades. 相似文献
998.
The effect of Si on the austenite stabilization, martensite morphology, and magnetic properties in Fe-26%Ni-x%Si (x=3.5, 5, and 6) alloys have been studied by means of transmission electron microscopy (TEM) and M?ssbauer spectroscopy techniques. TEM observations reveal that the martensite morphology is closely dependent on the Si content. The volume fraction changes of martensite and austenite phases, the hyperfine magnetic field, and isomer shift values have been determined by Mssbauer spectroscopy. The M?ssbauer study reveals that the hyperfine magnetic field, the isomer shift values and the volume fraction of martensite decrease with increasing Si content. 相似文献
999.
Elia J Glessner JT Wang K Takahashi N Shtir CJ Hadley D Sleiman PM Zhang H Kim CE Robison R Lyon GJ Flory JH Bradfield JP Imielinski M Hou C Frackelton EC Chiavacci RM Sakurai T Rabin C Middleton FA Thomas KA Garris M Mentch F Freitag CM Steinhausen HC Todorov AA Reif A Rothenberger A Franke B Mick EO Roeyers H Buitelaar J Lesch KP Banaschewski T Ebstein RP Mulas F Oades RD Sergeant J Sonuga-Barke E Renner TJ Romanos M Romanos J Warnke A Walitza S Meyer J Pálmason H Seitz C Loo SK Smalley SL 《Nature genetics》2012,44(1):78-84
Attention deficit hyperactivity disorder (ADHD) is a common, heritable neuropsychiatric disorder of unknown etiology. We performed a whole-genome copy number variation (CNV) study on 1,013 cases with ADHD and 4,105 healthy children of European ancestry using 550,000 SNPs. We evaluated statistically significant findings in multiple independent cohorts, with a total of 2,493 cases with ADHD and 9,222 controls of European ancestry, using matched platforms. CNVs affecting metabotropic glutamate receptor genes were enriched across all cohorts (P = 2.1 × 10(-9)). We saw GRM5 (encoding glutamate receptor, metabotropic 5) deletions in ten cases and one control (P = 1.36 × 10(-6)). We saw GRM7 deletions in six cases, and we saw GRM8 deletions in eight cases and no controls. GRM1 was duplicated in eight cases. We experimentally validated the observed variants using quantitative RT-PCR. A gene network analysis showed that genes interacting with the genes in the GRM family are enriched for CNVs in ~10% of the cases (P = 4.38 × 10(-10)) after correction for occurrence in the controls. We identified rare recurrent CNVs affecting glutamatergic neurotransmission genes that were overrepresented in multiple ADHD cohorts. 相似文献
1000.
Estimating the proportion of variation in susceptibility to schizophrenia captured by common SNPs 总被引:1,自引:0,他引:1
Lee SH DeCandia TR Ripke S Yang J;Schizophrenia Psychiatric Genome-Wide Association Study Consortium 《Nature genetics》2012,44(3):247-250
Schizophrenia is a complex disorder caused by both genetic and environmental factors. Using 9,087 affected individuals, 12,171 controls and 915,354 imputed SNPs from the Schizophrenia Psychiatric Genome-Wide Association Study (GWAS) Consortium (PGC-SCZ), we estimate that 23% (s.e. = 1%) of variation in liability to schizophrenia is captured by SNPs. We show that a substantial proportion of this variation must be the result of common causal variants, that the variance explained by each chromosome is linearly related to its length (r = 0.89, P = 2.6 × 10(-8)), that the genetic basis of schizophrenia is the same in males and females, and that a disproportionate proportion of variation is attributable to a set of 2,725 genes expressed in the central nervous system (CNS; P = 7.6 × 10(-8)). These results are consistent with a polygenic genetic architecture and imply more individual SNP associations will be detected for this disease as sample size increases. 相似文献