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41.
The goal of the Plant Ontology Consortium is to produce structured controlled vocabularies, arranged in ontologies, that can be applied to plant-based database information even as knowledge of the biology of the relevant plant taxa (e.g. development, anatomy, morphology, genomics, proteomics) is accumulating and changing. The collaborators of the Plant Ontology Consortium (POC) represent a number of core participant database groups. The Plant Ontology Consortium is expanding the paradigm of the Gene Ontology Consortium (http://www.geneontology.org). Various trait ontologies (agronomic traits, mutant phenotypes, phenotypes, traits, and QTL) and plant ontologies (plant development, anatomy [incl. morphology]) for several taxa (Arabidopsis, maize/corn/Zea mays and rice/Oryza) are under development. The products of the Plant Ontology Consortium will be open-source.  相似文献   
42.
Polar auxin transport plays a divergent role in plant growth and developmental processes including root and embryo development, vascular pattern formation and cell elongation. Recently isolated Arabidopsis pin gene family was believed to encode a component of auxin efflux carrier (G(?)lweiler et al, 1998). Based on the Arabidopsis pin1 sequence we have isolated a Brassica juncea cDNA (designated Bjpin1), which encoded a 70-kDa putative auxin efflux carrier. Deduced BjPIN1 shared 65% identities at protein level with AtPINl and was highly homologous to other putative PIN proteins of Arabidopsis (with highest homology to AtPIN3). Hydrophobic analysis showed similar structures between BjPINl and AtPIN proteins. Presence of 6 exons (varying in size between 65 bp and 1229 bp) and 5 introns (sizes between 89 bp and 463 bp) in the genomic fragment was revealed by comparing the genomic and cDNA sequences. Northern blot analysis indicated that Bjpin1 was expressed in most of the tissues tested, with a relatively h  相似文献   
43.
Mutations in the coding region of the methyl-CpG-binding protein 2 ( MECP2) gene cause Rett syndrome and have also been reported in a number of X-linked mental retardation syndromes. Furthermore, such mutations have recently been described in a few autistic patients. In this study, a large sample of individuals with autism was screened in order to elucidate systematically whether specific mutations in MECP2 play a role in autism. The mutation analysis of the coding sequence of the gene was performed by denaturing high-pressure liquid chromatography and direct sequencing. Taken together, 14 sequence variants were identified in 152 autistic patients from 134 German families and 50 unrelated patients from the International Molecular Genetic Study of Autism Consortium affected relative-pair sample. Eleven of these variants were excluded for having an aetiological role as they were either silent mutations, did not cosegregate with autism in the pedigrees of the patients or represented known polymorphisms. The relevance of the three remaining mutations towards the aetiology of autism could not be ruled out, although they were not localised within functional domains of MeCP2 and may be rare polymorphisms. Taking into account the large size of our sample, we conclude that mutations in the coding region of MECP2 do not play a major role in autism susceptibility. Therefore, infantile autism and Rett syndrome probably represent two distinct entities at the molecular genetic level.  相似文献   
44.
The evolutionarily conserved proteins Par-6, atypical protein kinase C (aPKC), Cdc42 and Par-3 associate to regulate cell polarity and asymmetric cell division, but the downstream targets of this complex are largely unknown. Here we identify direct physiological interactions between mammalian aPKC, murine Par-6C (mPar-6C) and Mlgl, the mammalian orthologue of the Drosophila melanogaster tumour suppressor Lethal (2) giant larvae. In cultured cell lines and in mouse brain, aPKC, mPar-6C and Mlgl form a multiprotein complex in which Mlgl is targeted for phosphorylation on conserved serine residues. These phosphorylation sites are important for embryonic fibroblasts to polarize correctly in response to wounding and may regulate the ability of Mlgl to direct protein trafficking. Our data provide a direct physical and regulatory link between proteins of distinct polarity complexes, identify Mlgl as a functional substrate for aPKC in cell polarization and indicate that aPKC is directed to cell polarity substrates through a network of protein-protein interactions.  相似文献   
45.
46.
The use of in vitro gene reporter assays is becoming increasingly widespread in biology and particularly in drug metabolism, where the need for rapid screening of novel compounds is a driving factor. There is, however, little standardization of technique in the control of such assays, nor in the interpretation of results. This leads to confusion in the literature, with the possibility of a single piece of data being interpreted by several different methods, potentially giving vastly differing results. We have developed a reporter gene assay methodology that controls for many biological and experimental variables in the system and allows the application of a mathematical model to determine statistical significance between groups. Use of this methodology, we feel, allows an accurate and reproducible method of analyzing in vitro reporter gene assay data and increases its value as a biological tool.  相似文献   
47.
中国夜蛾科昆虫区系初步研究(鳞翅目:双孔亚目)   总被引:5,自引:0,他引:5  
对我国分布记载较详细的1410种夜蛾科昆虫区系分析结果表明:1)在世界昆虫区系中,可分为17个分布型,以东洋界种类最多,占35.6%;古北界种类居第二,占33.0%;古北界和东洋界共有种类居第三,占23.0%。2)中国夜蛾科昆虫主要由古北界种类、东洋界种类、古北界和东洋界共有种类组成,占总数的91.7%;与澳洲界共有67种,占4.8%;与非洲界共有51种,占3.6%;与新北界共有23种,占1.6%  相似文献   
48.
为了喝到美味的花蜜,一只大黄蜂不得不在摇摆的花瓣间保持身体的平衡。根据一项新的研究,蜜蜂在采蜜的过程中得到了植物的帮助。在80%的开花植物中发现的锥形细胞提供了一个坚实的落脚点,并且使授粉的机会大为增加。  相似文献   
49.

Background

High-throughput sequencing has enabled detailed insights into complex microbial environments, including the human gut microbiota. The accuracy of the sequencing data however, is reliant upon appropriate storage of the samples prior to DNA extraction. The aim of this study was to conduct the first MiSeq sequencing investigation into the effects of faecal storage on the microbiota, compared to fresh samples. Culture-based analysis was also completed.

Methods

Seven faecal samples were collected from healthy adults. Samples were separated into fresh (DNA extracted immediately), snap frozen on dry ice and frozen for 7 days at -80°C prior to DNA extraction or samples frozen at -80°C for 7 days before DNA extraction. Sequencing was completed on the Illumina MiSeq platform. Culturing of total aerobes, anaerobes and bifidobacteria was also completed.

Results

No significant differences at phylum or family levels between the treatment groups occurred. At genus level only Faecalibacterium and Leuconostoc were significantly different in the fresh samples compared to the snap frozen group (p = 0.0298; p = 0.0330 respectively). Diversity analysis indicated that samples clustered based on the individual donor, rather than by storage group. No significant differences occurred in the culture-based analysis between the fresh, snap or -80°C frozen samples.

Conclusions

Using the MiSeq platform coupled with culture-based analysis, this study highlighted that limited significant changes in microbiota occur following rapid freezing of faecal samples prior to DNA extraction. Thus, rapid freezing of samples prior to DNA extraction and culturing, preserves the integrity of the microbiota.  相似文献   
50.
The labelling reagent 2-[18F]fluoroethylazide was used in a traceless Staudinger ligation. This reaction was employed to obtain the GABAA receptor binding 6-benzyl-4-oxo-1,4-dihydro-quinoline-3-carboxylic acid (2-[18F]fluoroethyl) amide. The radiotracer was prepared with a non-decay corrected radiochemical yield of 7%, a radiochemical purity >95% and a specific radioactivity of 0.9 GBq/μmol. The compound showed low brain penetration in normal rats. A series of fluoroalkyl 4-quinolone analogues with nanomolar to sub-nanomolar affinity for the GABAA receptor has been prepared as well.  相似文献   
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