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71.
The primary structure of a protein molecule comprises a linear chain of amino acid residues. Certain parts of this linear chain are unique in nature and function. They can be classified under different categories and their roles studied in detail. Two such unique categories are the palindromic sequences and the Single Amino Acid Repeats (SAARs), which plays a major role in the structure, function and evolution of the protein molecule. In spite of their presence in various protein sequences, palindromes have not yet been investigated in detail. Thus, to enable a comprehensive understanding of these sequences, a computing engine, PPS, has been developed. The users can search the occurrences of palindromes and SAARs in all the protein sequences available in various databases and can view the three-dimensional structures (in case it is available in the known three-dimensional protein structures deposited to the Protein Data Bank) using the graphics plug-in Jmol. The proposed server is the first of its kind and can be freely accessed through the World Wide Web.

Availability

URL http://pranag.physics.iisc.ernet.in/pps/  相似文献   
72.
Cytokines’ secretion from the decidua and trophoblast cells has been known to regulate trophoblast cell functions, such as Extravillous trophoblasts (EVTs) cell migration and invasion and remodeling of spiral arteries. Defective angiogenesis and spiral arteries transformation are mainly caused by proinflammatory cytokines and excessive thrombin generation during preeclampsia. Monocyte chemotactic protein-1 (MCP-1), a crucial cytokine, has a role in maintaining normal pregnancy. In this study, we explored whether thrombin regulates the secretion of MCP-1 in HTR-8/SVneo cells; if yes, what is its function? We used HTR-8/SVneo cells, developed from ?rst trimester villous explants of early pregnancy, as the model of EVTs. MCP-1 gene silencing was performed using gene-specific siRNA. qPCR and ELISA were performed to estimate the expression and secretion of MCP-1. Here, we found that thrombin enhanced the secretion of MCP-1 in HTR-8/SVneo cells. Proteinase-activated receptor-1 (PAR-1) was found as the primary receptor, regulating MCP-1 secretion in these cells. Furthermore, MCP-1 secretion is modulated via protein kinase C (PKC) α, β, and Rho/Rho-kinase-dependent pathways. Thrombin negatively regulates HTR-8/SVneo cells’ ability to mimic tube formation in an MCP-1 dependent manner. In conclusion, we propose that thrombin-controlled MCP-1 secretion may play an essential role in normal placental development and successful pregnancy maintenance. Improper thrombin production and MCP-1 secretion during pregnancy might cause inadequate vascular formation and transformation of spiral arteries, which may contribute to pregnancy disorders, such as preeclampsia.  相似文献   
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In this study, 49 public school mental health practitioners (school counselors, school psychologists, and school social workers) completed a survey about working with students’ dreams. The majority of these practitioners reported having at least one student bring up dreams during counseling, more frequently with troubling dreams and nightmares or when coping with grief. Results showed that practitioners were less likely to talk about dreams with students who had been identified with an adjustment disorder, psychosis, or eating disorder; those who were oppositional or ill; and those who struggled with substance abuse problems. Although most practitioners did not feel competent working with children’s dreams and reported minimal training in dream work, they were interested in learning more about children’s dreams and potential uses of dream work in supportive counseling. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Defensins are small cysteine rich peptides with a molecular mass of 5-10 kDa and some of them exhibit potent antifungal activity. We have cloned the coding region of a cDNA of 225 bp cysteine rich defensin, named as Tfgd1, from the legume Trigonella foenum-graecum. The amino acid sequence deduced from the coding region comprised 74 amino acids, of which the N-terminal 27 amino acids constituted the signal peptide and the mature peptide comprised 47 amino acids. The protein is characterized by the presence of eight cysteine resisdues, conserved in the various plant defensins forming four disulphide bridges, which stabilize the mature peptide. The recombinant protein expressed in E coli exhibited antifungal activity against the broad host range fungus, Rhizoctonia solani and the peanut leaf spot fungus, Phaeoisariopsis personata.  相似文献   
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NBS-encoding genes play a critical role in the plant defense system. Wild relatives of crop plants are rich reservoirs of plant defense genes. Here, we performed a stringent genome-wide identification of NBS-encoding genes in three cultivated and eight wild Oryza species, representing three different genomes (AA, BB, and FF) from four continents. A total of 2688 NBS-encoding genes were identified from 11 Oryza genomes. All the three progenitor species of cultivated rice, namely O. barthii, O. rufipogon, and O. nivara, were the richest reservoir of NBS-encoding genes (214, 313, and 307 respectively). Interestingly, the two Asian cultivated species showed a contrasting pattern in the number of NBS-encoding genes. While indica subspecies maintained nearly equal number of NBS genes as its progenitor (309 and 313), the japonica subspecies had retained only two third in the course of evolution (213 and 307). Other major sources for NBS-encoding genes could be (i) O. longistaminata since it had the highest proportion of NBS-encoding genes and (ii) O. glumaepatula as it clustered distinctly away from the rest of the AA genome species. The present study thus revealed that NBS-encoding genes can be exploited from the primary gene pool for disease resistance breeding in rice.  相似文献   
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Protoplasts derived from hypocotyls of seedlings grown on half-strength MS medium containing 1% sucrose were cultured at a density of 5×104 ml-1 in Kao's medium supplemented with 1.0 mgl-12,4-D, 0.1 mgl-1 NAA and 0.5 mgl-1 zeatin riboside. After three days of culture in darkness at 25±1°C, cultures were transferred to light (70 Em-2s-1) in a 16/8 h ligø ht/dark cycle. Cultures were diluted on the 7th, 10th and 13th day with Kao's medium containing 3.4% sucrose, 0.1 mgl-1 2,4-dichlorophenoxyacetic acid and 1.0 mgl-1 benzyladenine. On the fifteenth day, microcalli were plated on K3 medium gelled with 0.5% agarose (Type 1, low EEO, Sigma). After a further period of two weeks, transfers were made to specific media to achieve either organogenesis or somatic embryogenesis. Time taken from plating protoplasts to obtaining plantlets is 8–10 weeks. Using this procedure, several hundred regenerated plants have been hardened in a growth chamber and transferred to soil.  相似文献   
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