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排序方式: 共有903条查询结果,搜索用时 15 毫秒
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Leo T. H. Tang Meera Trivedi Jenna Freund Christopher J. Salazar Maisha Rahman Nelson J. Ramirez-Suarez Garrett Lee Yu Wang Barth D. Grant Hannes E. Bülow 《PLoS genetics》2021,17(7)
The assembly of neuronal circuits involves the migrations of neurons from their place of birth to their final location in the nervous system, as well as the coordinated growth and patterning of axons and dendrites. In screens for genes required for patterning of the nervous system, we identified the catp-8/P5A-ATPase as an important regulator of neural patterning. P5A-ATPases are part of the P-type ATPases, a family of proteins known to serve a conserved function as transporters of ions, lipids and polyamines in unicellular eukaryotes, plants, and humans. While the function of many P-type ATPases is relatively well understood, the function of P5A-ATPases in metazoans remained elusive. We show here, that the Caenorhabditis elegans ortholog catp-8/P5A-ATPase is required for defined aspects of nervous system development. Specifically, the catp-8/P5A-ATPase serves functions in shaping the elaborately sculpted dendritic trees of somatosensory PVD neurons. Moreover, catp-8/P5A-ATPase is required for axonal guidance and repulsion at the midline, as well as embryonic and postembryonic neuronal migrations. Interestingly, not all axons at the midline require catp-8/P5A-ATPase, although the axons run in the same fascicles and navigate the same space. Similarly, not all neuronal migrations require catp-8/P5A-ATPase. A CATP-8/P5A-ATPase reporter is localized to the ER in most, if not all, tissues and catp-8/P5A-ATPase can function both cell-autonomously and non-autonomously to regulate neuronal development. Genetic analyses establish that catp-8/P5A-ATPase can function in multiple pathways, including the Menorin pathway, previously shown to control dendritic patterning in PVD, and Wnt signaling, which functions to control neuronal migrations. Lastly, we show that catp-8/P5A-ATPase is required for localizing select transmembrane proteins necessary for dendrite morphogenesis. Collectively, our studies suggest that catp-8/P5A-ATPase serves diverse, yet specific, roles in different genetic pathways and may be involved in the regulation or localization of transmembrane and secreted proteins to specific subcellular compartments. 相似文献
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Song Y Zong H Trivedi ER Vesper BJ Waters EA Barrett AG Radosevich JA Hoffman BM Meade TJ 《Bioconjugate chemistry》2010,21(12):2267-2275
Magnetic resonance imaging (MRI) has long been used clinically and experimentally as a diagnostic tool to obtain three-dimensional, high-resolution images of deep tissues. These images are enhanced by the administration of contrast agents such as paramagnetic Gd(III) complexes. Herein, we describe the preparation of a series of multimodal imaging agents in which paramagnetic Gd(III) complexes are conjugated to a fluorescent tetrapyrrole, namely, a porphyrazine (pz). Zinc metalated pzs conjugated to one, four, or eight paramagnetic Gd(III) complexes are reported. Among these conjugates, Zn-Pz-8Gd(III) exhibits an ionic relaxivity four times that of the monomeric Gd(III) agent, presumably because of increased molecular weight and a molecular relaxivity that is approximately thirty times larger, while retaining the intense electronic absorption and emission of the unmodified pz. Unlike current clinical MR agents, Zn-Pz-1Gd(III) is taken up by cells. This probe demonstrates intracellular fluorescence by confocal microscopy and provides significant contrast enhancement in MR images, as well as marked phototoxicity in assays of cellular viability. These results suggest that pz agents possess a new potential for use in cancer imaging by both MRI and near-infrared (NIR) fluorescence, while acting as a platform for photodynamic therapy. 相似文献
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Vishwas A. Bapat Prabodh K. Trivedi Antara Ghosh Vidhu A. Sane Thumballi R. Ganapathi Pravendra Nath 《Biotechnology advances》2010
Development and ripening in fruit is a unique phase in the life cycle of higher plants which encompasses several stages progressively such as fruit development, its maturation, ripening and finally senescence. During ripening phase, several physiological and biochemical changes take place through differential expression of various genes that are developmentally regulated. Expression and/or suppression of these genes contribute to various changes in the fruit that make it visually attractive and edible. However, in fleshy fruit massive losses accrue during post harvest handling of the fruit which may run into billions of dollars worldwide. This encouraged scientists to look for various ways to save these losses. Genetic engineering appears to be the most promising and cost effective means to prevent these losses. Most fleshy fruit ripen in the presence of ethylene and once ripening has been initiated proceeds uncontrollably. Ethylene evokes several responses during ripening through a signaling cascade and thousands of genes participate which not only sets in ripening but also responsible for its spoilage. Slowing down post ripening process in fleshy fruit has been the major focus of ripening-related research. In this review article, various developments that have taken place in the last decade with respect to identifying and altering the function of ripening-related genes have been described. Role of ethylene and ethylene-responsive genes in ripening of fleshy fruit is also included. Taking clues from the studies in tomato as a model fruit, few case studies are reviewed. 相似文献
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Mehar H. Asif Shrikant S. Mantri Ayush Sharma Anukool Srivastava Ila Trivedi Priya Gupta Chandra S. Mohanty Samir V. Sawant Rakesh Tuli 《Tree Genetics & Genomes》2010,6(6):941-952
Jatropha curcas is an important non-edible oil seed tree species and is considered a promising source of biodiesel. The complete nucleotide
sequence of J. curcas chloroplast genome (cpDNA) was determined by pyrosequencing and gaps filled by Sanger sequencing. The cpDNA is a circular
molecule of 163,856 bp in length and codes for 110 distinct genes (78 protein coding, four rRNA and 28 distinct tRNA). Genome
organisation and arrangement are similar to the reported angiosperm chloroplast genome. However, in Jatropha, the infA and the rps16 genes are non-functional. The inverted repeat (IR) boundary is within the rpl2 gene, and the 13 nucleotides at the ends of the two duplicate genes are different. Repeat analysis suggests the presence
of 72 repeat regions (>30 bp) apart from the IR; of these, 48 were direct and 24 were palindromic repeats. Phylogenetic analysis
of 81 protein coding chloroplast genes from 65 taxa by maximum parsimony, maximum likelihood and minimum evolution analyses
at 100 bootstraps provide strong support for the placement of inaperturate crotonoids of which Jatropha is a member as sister to articulated crotonoids of which Manihot is a member. 相似文献
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Rajeev K. Singh Kuldeep K. Lal Vindhya Mohindra Peyush Punia Rama S. Sah Akhilesh K. Mishra Rajesh Kumar B. N. Mishra W. S. Lakra 《Biochemical genetics》2010,48(9-10):760-778
The population structure of Labeo calbasu from 11 rivers belonging to the Indus, Ganges, Bhima, Mahanadi, and Godavari basins was investigated using allozyme marker systems. Seven out of 20 allozyme loci (35%) were polymorphic (P < 0.99). Both probability and score tests indicated significant deviation of genotype proportions from Hardy–Weinberg expectations at two loci, XDH* (Mahanadi, Bhima, and Godavari) and G6PDH* (Mahanadi). A pairwise genetic homogeneity test and F ST values indicated a low-to-moderate level (0.0515) of genetic structuring in the wild population of L. calbasu. AMOVA analysis also indicated moderate differentiation among the samples from different river basins. Analysis for genetic bottleneck was performed under the infinite allele model. The study revealed nine genetic stocks of L. calbasu from the natural population across Indian rivers. Evidence of genetic bottlenecks in some rivers was also revealed. 相似文献