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991.
Grant SL Shulman Y Tibbo P Hampson DR Baker GB 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2006,844(2):278-282
A simple and versatile methodology using high-performance liquid chromatography (HPLC) with fluorimetric detection was developed to simultaneously determine d-serine along with other metabolically related neuroactive amino acids in the glutamatergic system: L-serine, L-glutamate, L-glutamine, and glycine. On-column sensitivity was in the lower picomole range. Of two chiral thiol reagents investigated, amino acid derivatives of o-phthaldialdehyde (OPA) in combination with N-isobutyryl-L-cysteine were found to have consistently higher responses than their corresponding N-tert-butyloxycarbonyl-L-cysteine derivatives. This methodology was applied to the quantitative detection of amino acids in human plasma and lays the foundation for further investigations of the role of neuroactive amino acids in the pathophysiology and treatment of neurological and psychiatric disorders. 相似文献
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Eisen JA Coyne RS Wu M Wu D Thiagarajan M Wortman JR Badger JH Ren Q Amedeo P Jones KM Tallon LJ Delcher AL Salzberg SL Silva JC Haas BJ Majoros WH Farzad M Carlton JM Smith RK Garg J Pearlman RE Karrer KM Sun L Manning G Elde NC Turkewitz AP Asai DJ Wilkes DE Wang Y Cai H Collins K Stewart BA Lee SR Wilamowska K Weinberg Z Ruzzo WL Wloga D Gaertig J Frankel J Tsao CC Gorovsky MA Keeling PJ Waller RF Patron NJ Cherry JM Stover NA Krieger CJ del Toro C Ryder HF Williamson SC Barbeau RA 《PLoS biology》2006,4(9):e286
The ciliate Tetrahymena thermophila is a model organism for molecular and cellular biology. Like other ciliates, this species has separate germline and soma functions that are embodied by distinct nuclei within a single cell. The germline-like micronucleus (MIC) has its genome held in reserve for sexual reproduction. The soma-like macronucleus (MAC), which possesses a genome processed from that of the MIC, is the center of gene expression and does not directly contribute DNA to sexual progeny. We report here the shotgun sequencing, assembly, and analysis of the MAC genome of T. thermophila, which is approximately 104 Mb in length and composed of approximately 225 chromosomes. Overall, the gene set is robust, with more than 27,000 predicted protein-coding genes, 15,000 of which have strong matches to genes in other organisms. The functional diversity encoded by these genes is substantial and reflects the complexity of processes required for a free-living, predatory, single-celled organism. This is highlighted by the abundance of lineage-specific duplications of genes with predicted roles in sensing and responding to environmental conditions (e.g., kinases), using diverse resources (e.g., proteases and transporters), and generating structural complexity (e.g., kinesins and dyneins). In contrast to the other lineages of alveolates (apicomplexans and dinoflagellates), no compelling evidence could be found for plastid-derived genes in the genome. UGA, the only T. thermophila stop codon, is used in some genes to encode selenocysteine, thus making this organism the first known with the potential to translate all 64 codons in nuclear genes into amino acids. We present genomic evidence supporting the hypothesis that the excision of DNA from the MIC to generate the MAC specifically targets foreign DNA as a form of genome self-defense. The combination of the genome sequence, the functional diversity encoded therein, and the presence of some pathways missing from other model organisms makes T. thermophila an ideal model for functional genomic studies to address biological, biomedical, and biotechnological questions of fundamental importance. 相似文献
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997.
Gorr IH Reis A Boos D Wühr M Madgwick S Jones KT Stemmann O 《Nature cell biology》2006,8(9):1035-1037
Separase not only triggers anaphase of meiosis I by proteolytic cleavage of cohesin on chromosome arms, but in vitro vertebrate separase also acts as a direct inhibitor of cyclin-dependent kinase 1 (Cdk1) on liberation from the inhibitory protein, securin. Blocking separase-Cdk1 complex formation by microinjection of anti-separase antibodies prevents polar-body extrusion in vertebrate oocytes. Importantly, proper meiotic maturation is rescued by chemical inhibition of Cdk1 or expression of Cdk1-binding separase fragments lacking cohesin-cleaving activity. 相似文献
998.
Collecting and organizing systematic sets of protein data 总被引:3,自引:0,他引:3
Albeck JG MacBeath G White FM Sorger PK Lauffenburger DA Gaudet S 《Nature reviews. Molecular cell biology》2006,7(11):803-812
Systems biology, particularly of mammalian cells, is data starved. However, technologies are now in place to obtain rich data, in a form suitable for model construction and validation, that describes the activities, states and locations of cell-signalling molecules. The key is to use several measurement technologies simultaneously and, recognizing each of their limits, to assemble a self-consistent compendium of systematic data. 相似文献
999.
Holland AM Micallef SJ Li X Elefanty AG Stanley EG 《Genesis (New York, N.Y. : 2000)》2006,44(6):304-307
The pancreatic and duodenal homeobox gene 1 (Pdx1) has multiple roles in the specification and development of foregut endoderm-derived tissues. We report the characterization of a mouse line in which the gene encoding green fluorescent protein (GFP) has been targeted to the Pdx1 locus, allowing the visualization of Pdx1 expressing cells. Analysis of GFP expression during development showed that the reporter faithfully reproduced the known expression pattern of Pdx1. We demonstrate the utility of this mouse line for the isolation of Pdx1(+) cells by fluorescence-activated cell sorting and for the real-time observation of Pdx1(+) cells in an ex vivo embryonic pancreas culture system. This mouse model should prove useful for the study of pancreas development and regeneration. 相似文献
1000.
Neuron-specific enolase-cre mouse line with cre activity in specific neuronal populations 总被引:1,自引:0,他引:1
Kwon CH Zhou J Li Y Kim KW Hensley LL Baker SJ Parada LF 《Genesis (New York, N.Y. : 2000)》2006,44(3):130-135
To establish genetic tools for conditional gene deletion in mouse neurons, we generated two independent neuron-specific enolase (Nse)-cre transgenic lines. The transgenic line termed Nse-cre(CK1) showed cre activity in most neuronal regions in the nervous system, while the Nse-cre(CK2) line exhibited a unique cre activity that has not been reported in other cre transgenic lines. Nse-cre(CK2) cre activity was detectable from embryogenesis and mostly restricted to neuronal regions. In postnatal brain, the Nse-cre(CK2) line exhibited cre activity limited to differentiated neurons in the cerebral cortex and hippocampus. Cre activity was assayed in several internal organs and sporadic activity was limited to the kidney and testis. We conclude that these cre lines will be useful for studying loss of gene function in specific neuronal populations. 相似文献