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61.
Serine proteases are among the most abundant granule constituents of several hematopoietic cell lineages including mast cells, neutrophils, cytotoxic T cells and NK cells. These proteases are stored in their active form in the cytoplasmic granules and in mammals are encoded from four different chromosomal loci: the chymase locus, the met-ase locus, the T cell tryptase and the mast cell tryptase locus. In order to study their appearance during vertebrate evolution we have performed a bioinformatic analysis of related genes and gene loci from a large panel of metazoan animals from sea urchins to placental mammals for three of these loci: the chymase, met-ase and granzyme A/K loci. Genes related to mammalian granzymes A and K were the most well conserved and could be traced as far back to cartilaginous fish. Here, the granzyme A and K genes were found in essentially the same chromosomal location from sharks to humans. However in sharks, no genes clearly identifiable as members of the chymase or met-ase loci were found. A selection of these genes seemed to appear with bony fish, but sometimes in other loci. Genes related to mammalian met-ase locus genes were found in bony fish. Here, the most well conserved member was complement factor D. However, genes distantly related to the neutrophil proteases were also identified in this locus in several bony fish species, indicating that this locus is also old and appeared at the base of bony fish. In fish, a few of the chymase locus-related genes were found in a locus with bordering genes other than the mammalian chymase locus and some were found in the fish met-ase locus. This indicates that a convergent evolution rather than divergent evolution has resulted in chymase locus-related genes in bony fish. 相似文献
62.
63.
Akula Ramakrishna Parvatam Giridhar Gokare Aswathanarayana Ravishankar 《Plant signaling & behavior》2011,6(6):800-809
Serotonin (5-hydroxytryptamine; SER) is one of the well-studied indoleamine neurotransmitters in vertebrates. Recently SER has also been reported in wide range of plant species. The precise function of SER at the physiological level, particularly growth regulation, flowering, xylem sap exudation, ion permeability and plant morphogenesis in plant system has not been clear. Though SER is found in different parts of plant species including leaves, stems, roots, fruits and seeds, the quantity of SER within plant tissues varies widely. SER has been recently shown as a plant hormone in view of its auxin-like activity. This brief review provides an overview of SER biosynthesis, localization, its role in plant morphogenesis and possible physiological functions in plants. This would certainly help to elucidate further the multiple roles of SER in plant morphogenesis. In the future it may form the basis for studies on involvement of SER in cellular signaling mechanisms in plants. Apart from these gaps in understanding the role of SER in ontogeny of plant physiology and ecological, adaptations have been emphasized. Thus, overall perspectives in this area of research and its possible implications have been presented.Key words: biosynthesis, growth regulation, occurrence, physiological functions, phytoserotonin, plant morphogenesis, serotonin 相似文献
64.
The effect of alkyl substitution (CH3, C2H5, n-C3H7, i-C3H7, and t-C4H9) on the hydrogen bond strengths (H-bond) of substituted amide-alcohol complexes has been systematically explored. B3LYP/aug-cc-pVDZ
method was applied to a total of 215 alkyl substituted amide-alcohol complexes to delineate the effect of substitution on
the H-bond strength; formamide-water complex is taken as reference point. Complexes are classified into five types depending
on the hydrogen donor, acceptor and the site of alkyl substitution (Type-IA, Type-IIA, Type-IB, Type-IIB and Type-III). The
strength of H-bond was correlated with geometrical parameters such as proton-acceptor (H∙∙∙∙Y) distance, the length of proton
donating bond (X–H). In all the complexes N–H and O–H stretching frequencies are red-shifted. The effect of alkyl substitution
on N–H and O–H stretching frequencies were analyzed. Topological parameters like electron density at H∙∙∙∙Y and X–H bond critical
points as derived from atom in molecules (AIM) theory was also evaluated. When C = O group is participating in H-bond, the
strength of H-bond decreases with increasing size of alcohols except for methanol (Type-IA, Type-III and Type-IB complexes).
But it increases with increasing size of alkyl groups on amide and decreases with bulky groups. In the case of N–H group as
H-bond donor, the strength of H-bond increases with increasing size of alcohols (Type-IIA and Type-IIB complexes) whereas
decreases with increasing size of alkyl groups on amide. Type-IA, IIA, IB and IIB complexes exhibit good correlations among
IE, H-bond distance and electron density at bcp. In Type-III complexes, average H-bond distance and sum of electron densities
shows better correlation with IEs than the corresponding individuals. The correlation of IE less with electron density at
RCP compared to sum of electron densities. 相似文献
65.
D. Chakradhar Ajay Narendra K. Nagaraju 《Archives Of Phytopathology And Plant Protection》2013,46(18):1809-1818
The present study was aimed to evaluate six indigenous plant extracts for their ability to protect maize from infestation by maize weevil Sitophilus zeamais (M). The plant extracts were tested for its toxicity by fumigation and grain surface coating methods. Further, the effects of botanical treatments on F1 progeny, seed emergence and antifungal activities were studied. The results indicated that the extracts of Eicchornia crassipes controlled the test insect in grain surface coating method (100%, P = 0.05). Further, the same plant extract had significantly reduced the development of F1 progeny (97 ± 0.7%). In germination experiments, T + UEx samples showed normal seed germination of maize. However, in T + Ex samples, the seed germination depended on the grain protectant efficacy of the tested botanical extracts. Always higher percantage seed germination was recorded in those treatments where there was less infestation. Extracts of Carica papaya had significantly reduced the incidence of seed-borne fungus Aspergillus flavus (4 ± 2.4%) and did not affect the seed germination when compared to other treatments and untreated control. 相似文献
66.
Malathi Surapaneni Lakshminarayan R. Vemireddy Hameedunnisa Begum B. Purushotham Reddy C. Neetasri J. Nagaraju S. Y. Anwar E. A. Siddiq 《Plant Systematics and Evolution》2013,299(7):1215-1229
Genetic analysis of 90 mango genotypes including juicy, table, dual and pickle types from different parts of Andhra Pradesh of India was carried out employing 143 mango-specific microsatellite markers. Of the 143, 34 were new mango-specific microsatellite loci isolated in the course of the present investigation by constructing an (CA) n and (TG) n -enriched genomic library. Characterization of the 90 genotypes resulted in the detection of 301 alleles from 106 polymorphic loci with an average of 2.87 alleles per locus and polymorphism information content of 0.67. UPGMA cluster analysis grouped all the genotypes into two major groups with a genetic similarity range of 47–88 %. Grouping of the genotypes based on the utility type was observed only at sub-cluster level. Study of population structure by a model-based STRUCTURE analysis revealed the germplasm to exist in four gene pools. Overall F st of 0.11 indicated genetic differentiation between the populations to be low. Analysis of molecular variance revealed that major proportion of the variation was within the individuals (62.25 %). The molecular marker-based study of genetic diversity suggests that the germplasm studied representing the kind of variability would be a valuable genetic resource for future breeding and association mapping in search for new and novel alleles. 相似文献
67.
A Systematic Search Method for the Identification of Tightly Packed Transmembrane Parallel α-Helices
Nagaraju Akula Nagarajan Pattabiraman 《Journal of biomolecular structure & dynamics》2013,31(6):625-634
Abstract Membrane proteins play a major role in number of biological processes such as signaling pathways. The determination of the three-dimensional structure of these proteins is increasingly important for our understanding of their structure-function relationships. Due to the difficulty in isolating membrane proteins for X-ray diffraction studies, computational techniques are being developed to generate the 3D structures of TM domains. Here, we present a systematic search method for the identification of energetically favorable and tightly packed transmembrane parallel α-helices. The first step in our systematic search method is the generation of 3D models for pairs of parallel helix bundles with all possible orientations followed by an energy-based filter to eliminate structures with severe non-bonded contacts. Then, a RMS-based filter was used to cluster these structures into families. Furthermore, these dimers were energy minimized using molecular mechanics force field. Finally, we identified the tightly packed parallel α-helices by using an interface surface area. To validate our search method, we compared our predicted GlycophorinA dimer structures with the reported NMR structures. With our search method, we are able to reproduce NMR structures of GPA with 0.9Å RMSD. In addition, by considering the reported mutational data on GxxxG motif interactions, twenty percent of our predicted dimers are within in the 2.0Å RMSD. The dimers obtained from our method were used to generate parallel trimeric and tetramer TM structures of GPA and found that the structure of GPA might exist only in a dimer form as reported earlier. 相似文献
68.
Nagaraju M. Kumar Anuj Rajasheker G. Manohar Rao D. Kavi Kishor P. B. 《Molecular biology reports》2020,47(10):7379-7390
Molecular Biology Reports - The DnaJ/Hsp40s, are important components in the chaperone machine, and play pivotal roles in plant growth, development and stress tolerance. Sorghum, the semi-arid... 相似文献
69.
Howell GR Libby RT Jakobs TC Smith RS Phalan FC Barter JW Barbay JM Marchant JK Mahesh N Porciatti V Whitmore AV Masland RH John SW 《The Journal of cell biology》2007,179(7):1523-1537
Here, we use a mouse model (DBA/2J) to readdress the location of insult(s) to retinal ganglion cells (RGCs) in glaucoma. We localize an early sign of axon damage to an astrocyte-rich region of the optic nerve just posterior to the retina, analogous to the lamina cribrosa. In this region, a network of astrocytes associates intimately with RGC axons. Using BAX-deficient DBA/2J mice, which retain all of their RGCs, we provide experimental evidence for an insult within or very close to the lamina in the optic nerve. We show that proximal axon segments attached to their cell bodies survive to the proximity of the lamina. In contrast, axon segments in the lamina and behind the eye degenerate. Finally, the Wlds allele, which is known to protect against insults to axons, strongly protects against DBA/2J glaucoma and preserves RGC activity as measured by pattern electroretinography. These experiments provide strong evidence for a local insult to axons in the optic nerve. 相似文献
70.
Shiradkar MR Murahari KK Gangadasu HR Suresh T Kalyan CA Panchal D Kaur R Burange P Ghogare J Mokale V Raut M 《Bioorganic & medicinal chemistry》2007,15(12):3997-4008
In the present study, a series of N-{4-[(4-amino-5-sulfanyl-4H-1,2,4-triazol-3-yl)methyl]-1,3-thiazol-2-yl}-2-substituted-amide (1a-d) derivatives were synthesized in good yields and characterized by IR, 1H NMR, mass spectral and elemental analyses. The compounds were evaluated for their preliminary in vitro antibacterial activity against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Salmonella typhosa and then were screened for antitubercular activity against Mycobacterium tuberculosis H37 Rv strain by broth microdilution assay method. The antibacterial data of the tested compounds indicated that most of the synthesized compounds showed better activity against bacteria compared to reference drugs. The in vitro antitubercular activity reports of tested compounds against M. tuberculosis strain H37 Rv showed moderate to better activity. 相似文献