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31.
The N-methyl-D-aspartate receptor (NMDAR) is a key molecule mediating brain plasticity related processes. Knowing that alternative splicing
of the NMDAR1 (NR1) subunit offers molecular diversity to NMDAR, controls the forward trafficking of the NR1 protein and is
important for placing NMDA receptors at synapses, we investigated herein the postnatal developmental expression and the influence
of visual deprivation on NR1 subunit splice variants in rat retina. Real-time PCR was performed using oligonucleotide primers
specific for N- terminal (NR1a, NR1b) and C-terminal splice variants (NR1-1, NR1-2, NR1-3, NR1-4). The developmental profiles
of mRNA expression levels of all NR1 isoforms peaked at the end of the third week. Dark rearing led to reductions in both
N- and C-terminal NR1 variants in several developmental ages and a significant interaction between age and visual experience
was observed for NR1a, NR1-2 and NR1-4 expression. Our results have demonstrated a developmental and visual experience-dependent
regulation of NR1 splicing in rat retina. 相似文献
32.
Messenger RNA localization involves the assembly of ribonucleoprotein particles (RNPs) and their subsequent transport along the cytoskeleton to their final destination. Here, we provide new evidence that microtubule-associated protein 2 (MAP2), calcium/calmodulin-dependent protein kinase II (CaMKIIα) and β-actin RNAs localize to dendrites in distinct RNPs, which contain--unexpectedly--very few RNA molecules. The number of MAP2 molecules per particle is affected by synaptic activity and Staufen 2, indicating that RNP composition is tightly controlled. Our data suggest that the independent localization of individual RNAs in low copy numbers could contribute to tighter temporal and spatial control of expression in neurons and synapse-specific plasticity. 相似文献
33.
FoxO3a transcriptional regulation of Bim controls apoptosis in paclitaxel-treated breast cancer cell lines 总被引:15,自引:0,他引:15
34.
Fu, G., Perona-Wright, G., and Barker, D. C. 1998.Leishmania braziliensis: Characterisation of a complex specific subtelomeric repeat sequence and its use in the detection of parasites.Experimental Parasitology90, 236–243. A 1.6-kb tandem repeat sequence had previously been identified in the subtelomeric region of mini- and megabase chromosomes fromLeishmania braziliensis.Southern hybridisation was used to demonstrate that the repeat is complex specific. The sequence was characterised in strains representing four species of theL. braziliensiscomplex. This data allowed an assessment of the evolutionary relationship of the four species. PCR primers targeted to the repeat amplify only DNA from species of theL. braziliensiscomplex. Titration assays indicate that a minimum of 50 fg of parasite DNA can be detected by PCR alone. Southern hybridisation increases the limit of detection to 5 fg. Interspecies variation in the repeat sequence enabled restriction enzyme digestion of PCR products to distinguish individual species within theL. braziliensiscomplex. 相似文献
35.
Tyrosine phosphorylation of mitochondrial pyruvate dehydrogenase kinase 1 is important for cancer metabolism 总被引:1,自引:0,他引:1
Hitosugi T Fan J Chung TW Lythgoe K Wang X Xie J Ge Q Gu TL Polakiewicz RD Roesel JL Chen GZ Boggon TJ Lonial S Fu H Khuri FR Kang S Chen J 《Molecular cell》2011,44(6):864-877
Many tumor cells rely on aerobic glycolysis instead of oxidative phosphorylation for their continued proliferation and survival. Myc and HIF-1 are believed to promote such a metabolic switch by, in part, upregulating gene expression of pyruvate dehydrogenase (PDH) kinase 1 (PDHK1), which phosphorylates and inactivates mitochondrial PDH and consequently pyruvate dehydrogenase complex (PDC). Here we report that tyrosine phosphorylation enhances PDHK1 kinase activity by promoting ATP and PDC binding. Functional PDC can form in mitochondria outside of the matrix in some cancer cells and PDHK1 is commonly tyrosine phosphorylated in human cancers by diverse oncogenic tyrosine kinases localized to different mitochondrial compartments. Expression of phosphorylation-deficient, catalytic hypomorph PDHK1 mutants in cancer cells leads to decreased cell proliferation under hypoxia and increased oxidative phosphorylation with enhanced mitochondrial utilization of pyruvate and reduced tumor growth in xenograft nude mice. Together, tyrosine phosphorylation activates PDHK1 to promote the Warburg effect and tumor growth. 相似文献
36.
37.
Birgit Schiller Georgia Makrypidi Ebrahim Razzazi-Fazeli Katharina Paschinger Julia Walochnik Iain B. H. Wilson 《The Journal of biological chemistry》2012,287(52):43191-43204
Glycans play key roles in host-pathogen interactions; thus, knowing the N-glycomic repertoire of a pathogen can be helpful in deciphering its methods of establishing and sustaining a disease. Therefore, we sought to elucidate the glycomic potential of the facultative amoebal parasite Acanthamoeba. This is the first study of its asparagine-linked glycans, for which we applied biochemical tools and various approaches of mass spectrometry. An initial glycomic screen of eight strains from five genotypes of this human pathogen suggested, in addition to the common eukaryotic oligomannose structures, the presence of pentose and deoxyhexose residues on their N-glycans. A more detailed analysis was performed on the N-glycans of a genotype T11 strain (4RE); fractionation by HPLC and tandem mass spectrometric analyses indicated the presence of a novel mannosylfucosyl modification of the reducing terminal core as well as phosphorylation of mannose residues, methylation of hexose and various forms of pentosylation. The largest N-glycan in the 4RE strain contained two N-acetylhexosamine, thirteen hexose, one fucose, one methyl, and two pentose residues; however, in this and most other strains analyzed, glycans with compositions of Hex8–9HexNAc2Pnt0–1 tended to dominate in terms of abundance. Although no correlation between pathogenicity and N-glycan structure can be proposed, highly unusual structures in this facultative parasite can be found which are potential virulence factors or therapeutic targets. 相似文献
38.
In this study we present a novel multiplex PCR assay for rapid and efficient detection of Lactobacillus delbrueckii subsp. bulgaricus. The accuracy of our method was confirmed by the successful identification of L. delbrueckii subsp. bulgaricus in commercial yoghurts and food supplements and it may be readily applied to the food industry. 相似文献
39.
Faisan Joseph P. Luhan Ma. Rovilla J. Sibonga Rema C. Mateo Jonalyn P. Ferriols Victor Marco Emmanuel N. Brakel Janina Ward Georgia M. Ross Stuart Bass David Stentiford Grant D. Brodie Juliet Hurtado Anicia Q. 《Journal of applied phycology》2021,33(4):2391-2405
Journal of Applied Phycology - Farmed eucheumatoids are the top aquaculture commodity in the Philippines, contributing more than 60% of total national aquaculture production by volume. Despite... 相似文献
40.
Innokentiy Maslennikov Martin Krupa Christopher Dickson Luis Esquivies Katherine Blain Georgia Kefala Senyon Choe Witek Kwiatkowski 《Journal of structural and functional genomics》2009,10(1):25-35
Abstract Bottlenecks in expression, solubilization, purification and crystallization hamper the structural study of integral membrane
proteins (IMPs). Successful crystallization is critically dependent on the purity, stability and oligomeric homogeneity of
an IMP sample. These characteristics are in turn strongly influenced by the type and concentration of the detergents used
in IMP preparation. By utilizing the techniques and analytical tools we earlier developed for the characterization of protein-detergent
complexes (PDCs) [21], we demonstrate that for successful protein extraction from E. coli membrane fractions, the solubilizing detergent associates preferentially to IMPs rather than to membrane lipids. Notably,
this result is contrary to the generally accepted mechanism of detergent-mediated IMP solubilization. We find that for one
particular member of the family of proteins studied (E. coli receptor kinases, which is purified in mixed multimeric states and oligomerizes through its transmembrane region), the protein
oligomeric composition is largely unaffected by a 10-fold increase in protein concentration, by alteration of micelle properties
through addition of other detergents to the PDC sample, or by a 20-fold variation in the detergent concentration used for
solubilization of the IMP from the membrane. We observed that the conditions used for expression of the IMP, which impact
protein density in the membrane, has the greatest influence on the IMP oligomeric structure. Finally, we argue that for concentrating
PDCs smaller than 30 kDa, stirred concentration cells are less prone to over-concentration of detergent and are therefore
more effective than centrifugal ultrafiltration devices. 相似文献