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991.
Cadherin-like proteins have been identified as putative receptors for the Bacillus thuringiensis Cry1A proteins in Heliothis virescens and Manduca sexta. Immunohistochemistry showed the cadherin-like proteins are present in the insect midgut apical membrane, which is the target site of Cry toxins. This subcellular localization is distinct from that of classical cadherins, which are usually present in cell-cell junctions. Immunoreactivity of the cadherin-like protein in the insect midgut was enhanced by Cry1Ac ingestion. We also generated a stable cell line Flp-InT-REX-293/Full-CAD (CAD/293) that expressed the H. virescens cadherin. As expected, the cadherin-like protein was mainly localized in the cell membrane. Interestingly, toxin treatment of CAD/293 cells caused this protein to relocalize to cell membrane subdomains. In addition, expression of H. virescens cadherin-like protein affects cell-cell contact and cell membrane integrity when the cells are exposed to activated Cry1Ab/Cry1Ac. 相似文献
992.
ESCRT-I core and ESCRT-II GLUE domain structures reveal role for GLUE in linking to ESCRT-I and membranes 总被引:15,自引:0,他引:15
ESCRT complexes form the main machinery driving protein sorting from endosomes to lysosomes. Currently, the picture regarding assembly of ESCRTs on endosomes is incomplete. The structure of the conserved heterotrimeric ESCRT-I core presented here shows a fan-like arrangement of three helical hairpins, each corresponding to a different subunit. Vps23/Tsg101 is the central hairpin sandwiched between the other subunits, explaining the critical role of its "steadiness box" in the stability of ESCRT-I. We show that yeast ESCRT-I links directly to ESCRT-II, through a tight interaction of Vps28 (ESCRT-I) with the yeast-specific zinc-finger insertion within the GLUE domain of Vps36 (ESCRT-II). The crystal structure of the GLUE domain missing this insertion reveals it is a split PH domain, with a noncanonical lipid binding pocket that binds PtdIns3P. The simultaneous and reinforcing interactions of ESCRT-II GLUE domain with membranes, ESCRT-I, and ubiquitin are critical for ubiquitinated cargo progression from early to late endosomes. 相似文献
993.
The analytical quality of point-of-care testing in the 'QAAMS' model for diabetes management in Australian aboriginal medical services
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Shephard MD Gill JP 《The Clinical biochemist. Reviews / Australian Association of Clinical Biochemists》2006,27(4):185-190
Type 2 diabetes mellitus and its major complication, renal disease, represent one of the most significant contemporary health problems facing Australia's Indigenous Aboriginal People. The Australian Government-funded Quality Assurance for Aboriginal Medical Services Program (QAAMS) provides a framework by which on-site point-of-care testing (POCT) for haemoglobin A1c (HbA(1c)) and now urine albumin:creatinine ratio (ACR) can be performed to facilitate better diabetes management in Aboriginal medical services. This paper provides updated evidence for the analytical quality of POCT in the QAAMS Program. The median imprecision for point-of-care (POC) HbA(1c) and urine ACR quality assurance (QA) testing has continually improved over the past six and half years, stabilising at approximately 3% for both analytes and proving analytically sound in Aboriginal hands. For HbA(1c), there was no statistical difference between the imprecision achieved by QAAMS and laboratory users of the Bayer DCA 2000 since the QAAMS program commenced (QAAMS CV 3.6% +/- 0.52, laboratory CV 3.4% +/- 0.42; p = 0.21, paired t-test). The Western Pacific Island of Tonga recently joined the QAAMS HbA(1c) Program indicating that the QAAMS model can also be applied internationally in other settings where the prevalence of diabetes is high. 相似文献
994.
Daljit Singh Arora Paramjit Kaur Gill 《World journal of microbiology & biotechnology》2005,21(6-7):1021-1028
Summary The present work reports the production of laccase, lignin peroxidase and manganese peroxidase by the little studied white-rot
fungus Phlebia floridensis under a variety of nutritional and physicochemical conditions. Among the different media and supplements the highest yields
of laccase, lignin peroxidase and manganese peroxidase were recorded in the presence of sugarcane bagasse, wheat straw and
rice straw, respectively. Laccase and manganese peroxidase activities were best expressed at a pH of 4.5 while lignin peroxidase
was optimally active at a lower pH. Laccase proved to be much more thermostable as compared to the other two enzymes. 相似文献
995.
Arun Dev Sharma Prabhjot Kaur Gill Sukhdev Singh Bhullar Prabhjeet Singh 《World journal of microbiology & biotechnology》2005,21(6-7):929-932
Summary An extracellular inulinase (fructanase)-producing strain of Penicillium purpurogenum was isolated from the rhizosphere soil of chicory. Conidia of this selected strain were subjected to simultaneous treatment
with NTG–UV (N-methyl-N′-nitro-N-nitrosoguanidine and ultraviolet radiation) and EtBr–UV (Ethidium bromide–ultraviolet radiation). After mutagenesis, colonies
were screened and among them a few were selected to carry out the inulinase study, which showed a significantly higher inulinase
activity with higher I/S (inulin/sucrose) ratio in all the selected colonies, indicating enhancement of inulinase production
after mutagenic treatments in all the selected mutants. 相似文献
996.
Alexander R Balasundaram A Batchelor M Brookings D Crépy K Crabbe T Deltent MF Driessens F Gill A Harris S Hutchinson G Kulisa C Merriman M Mistry P Parton T Turner J Whitcombe I Wright S 《Bioorganic & medicinal chemistry letters》2008,18(15):4316-4320
4-(1,3-Thiazol-2-yl)morpholine derivatives have been identified as potent and selective inhibitors of phosphoinositide 3-kinase. The SAR data of selected examples are presented and the in vivo profiling of compound 18 is shown to demonstrate the utility of this class of compounds in xenograft models of tumor growth. 相似文献
997.
Beveridge TJ Gill KE Hanlon CA Porrino LJ 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2008,363(1507):3257-3266
Cocaine users display profound impairments in executive function. Of all the components of executive function, inhibition, or the ability to withhold responding, has been studied the most extensively and may be most impaired. Consistent with these deficits, evidence from imaging studies points to dysregulation in medial and ventromedial prefrontal cortices, areas activated during performance of inhibition tasks. Other aspects of executive function including updating, shifting and decision making are also deficient in cocaine users, and these deficits are paralleled by abnormalities in patterns of prefrontal cortical activation. The extent to which cocaine plays a role in these effects, however, is not certain, and cannot be determined solely on the basis of human studies. Investigations using a non-human primate model of increasing durations of cocaine exposure revealed that initially the effects of cocaine were restricted to ventromedial and orbital prefrontal cortices, but as exposure was extended the intensity and spatial extent of the effects on functional activity also expanded rostrally and laterally. Given the spatial overlap in prefrontal pathology between human and monkey studies, these longitudinal mapping studies in non-human primates provide a unique window of understanding into the dynamic neural changes that are occurring early in human cocaine abuse. 相似文献
998.
Dean C. Thorburn David L. Morgan Andrew J. Rowland Howard S. Gill Eric Paling 《Environmental Biology of Fishes》2008,83(2):139-145
The dwarf sawfish, Pristis clavata, was captured in marine waters of King Sound and estuarine waters of the Fitzroy, May and Robinson Rivers, in the Kimberley
region of Western Australia. Observations of sexual maturity and annuli present on vertebrae suggest that the estuarine waters
of at least the Fitzroy River act as a nursery for the species, where immature individuals may remain for at least 3 years.
The capture of immature individuals in excess of 2,330 mm TL during the current study in addition to Peverell’s (Peverell
in Environ Biol Fishes 73:391–402, 2005) record of a mature male measuring 3,060 mm TL implies that the species may attain
far greater lengths than previously reported and that the common name may not be entirely appropriate. In contrast to the
sympatric freshwater sawfish Pristis microdon, the number of rostral teeth of individual P. clavata can not be used to differentiate males from females, with both sexes possessing an average of 42 rostral teeth. 相似文献
999.
Development and mapping of EST-derived simple sequence repeat markers for hexaploid wheat. 总被引:21,自引:0,他引:21
Ju-Kyung Yu Trevor M Dake Sukhwinder Singh David Benscher Wanlong Li Bikram Gill Mark E Sorrells 《Génome》2004,47(5):805-818
Expressed sequence tags (ESTs) are a valuable source of molecular markers. To enhance the resolution of an existing linkage map and to identify putative functional polymorphic gene loci in hexaploid wheat (Triticum aestivum L.), over 260,000 ESTs from 5 different grass species were analyzed and 5418 SSR-containing sequences were identified. Using sequence similarity analysis, 156 cross-species superclusters and 138 singletons were used to develop primer pairs, which were then tested on the genomic DNA of barley (Hordeum vulgare), maize (Zea mays), rice (Oryza sativa), and wheat. Three-hundred sixty-eight primer pairs produced PCR amplicons from at least one species and 227 primer pairs amplified DNA from two or more species. EST-SSR sequences containing dinucleotide motifs were significantly more polymorphic (74%) than those containing trinucleotides (56%), and polymorphism was similar for markers in both coding and 5' untranslated (UTR) regions. Out of 112 EST-SSR markers, 90 identified 149 loci that were integrated into a reference wheat genetic map. These loci were distributed on 19 of the 21 wheat chromosomes and were clustered in the distal chromosomal regions. Multiple-loci were detected by 39% of the primer pairs. Of the 90 mapped ESTs, putative functions for 22 were identified using BLASTX queries. In addition, 80 EST-SSR markers (104 loci) were located to chromosomes using nullisomic-tetrasomic lines. The enhanced map from this study provides a basis for comparative mapping using orthologous and PCR-based markers and for identification of expressed genes possibly affecting important traits in wheat. 相似文献
1000.