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41.
Somatic embryogenesis (SE) has been achieved from hypocotyl-derived callus culture in Pterocarpus marsupium. Ninety percent of hypocotyl explants (excised from 12-day-old in vitro germinated axenic seedlings) produced callus on Murashige and Skoog medium supplemented with 5 μM 2,4-dichlorophenoxyacetic acid and 1 μM a 6-benzyladenine (BA). Induction of SE occurred after transfer of callus clumps (200 ± 20 mg fresh mass) to MS medium supplemented with BA at 2.0 μM, where a maximum of 23.0 ± 0.88 globular stage embryos per callus clump were observed after 4 weeks of culture. Subculturing of these embryos on MS medium supplemented with 0.5 μM BA, 0.1 μM α-naphthalene acetic acid and 10 μM abscisic acid significantly enhanced the maturation of somatic embryos to early cotyledonary stage, where 21.4 ± 0.32 embryos per callus clump were recorded after 4 weeks of culture. Of 30-well developed somatic embryos, 16.6 ± 0.33 germinated and subsequently converted into plantlets on half-strength MS medium supplemented with 1.0 μM BA. The morphologically normal plantlets with well-developed roots were first transferred to 1/4-liquid MS medium for 48 h and then to pots containing autoclaved soilrite and acclimatized in a culture room. Thereafter, they were transferred to a greenhouse, where 60% of them survived. 相似文献
42.
Rebecca Phillips Mattias Svensson Naveed Aziz Asher Maroof Najmeeyah Brown Lynette Beattie Nathalie Signoret Paul M. Kaye 《PLoS pathogens》2010,6(3)
Highly phagocytic macrophages line the marginal zone (MZ) of the spleen and the lymph node subcapsular sinus. Although these macrophages have been attributed with a variety of functions, including the uptake and clearance of blood and lymph-borne pathogens, little is known about the effector mechanisms they employ after pathogen uptake. Here, we have combined gene expression profiling and RNAi using a stromal macrophage cell line with in situ analysis of the leishmanicidal activity of marginal zone macrophages (MZM) and marginal metallophilic macrophages (MMM) in wild type and gene targeted mice. Our data demonstrate a critical role for interferon regulatory factor-7 (IRF-7) in regulating the killing of intracellular Leishmania donovani by these specialised splenic macrophage sub-populations. This study, therefore, identifies a new role for IRF-7 as a regulator of innate microbicidal activity against this, and perhaps other, non-viral intracellular pathogens. This study also highlights the importance of selecting appropriate macrophage populations when studying pathogen interactions with this functionally diverse lineage of cells. 相似文献
43.
Within the medial frontal cortex, the supplementary eye field (SEF), supplementary motor area (SMA), and pre-SMA have been implicated in the control of voluntary action, especially during motor sequences or tasks involving rapid choices between competing response plans. However, the precise roles of these areas remain controversial. Here, we study two extremely rare patients with microlesions of the SEF and SMA to demonstrate that these areas are critically involved in unconscious and involuntary motor control. We employed masked-prime stimuli that evoked automatic inhibition in healthy people and control patients with lateral premotor or pre-SMA damage. In contrast, our SEF/SMA patients showed a complete reversal of the normal inhibitory effect--ocular or manual--corresponding to the functional subregion lesioned. These findings imply that the SEF and SMA mediate automatic effector-specific suppression of motor plans. This automatic mechanism may contribute to the participation of these areas in the voluntary control of action. 相似文献
44.
Polyclonal antibody bound Sepharose 4B support has been exploited for the immobilization of bitter gourd peroxidase directly from ammonium sulphate precipitated proteins. Immunoaffinity immobilized bitter gourd peroxidase exhibited high yield of immobilization. IgG-Sepharose 4B bound bitter gourd peroxidase showed a higher stability against heat, chaotropic agents (urea and guanidinium chloride), detergents (cetyl trimethyl ammonium bromide and Surf Excel), proteolytic enzyme (trypsin) and water-miscible organic solvents (propanol, THF and dioxane). The activity of immobilized bitter gourd peroxidase was significantly enhanced in the presence of cetyl trimethyl ammonium bromide and after treatment with trypsin as compared to soluble enzyme. 相似文献
45.
Fatima Abreeq Husain Tajammul Suhel Mohammad Prasad Sheo Mohan Singh Vijay Pratap 《Journal of Plant Growth Regulation》2022,41(1):163-177
Journal of Plant Growth Regulation - It is a well-established fact that nitric oxide (NO) is a multifaceted signaling molecule, which plays diverse role in organisms. In the past two decades,... 相似文献
46.
Mahmood Rasool Arif Malik Abdul Manan Khuram Aziz Amna Mahmood Saima Zaheer Naveed Shuja Mahmood Husain Qazi Mohammad Amjad Kamal Sajjad Karim 《Saudi Journal of Biological Sciences》2015,22(6):739-743
The present study was designed to explore the antioxidative status and circulating biochemical markers having a potential role in the pathogenesis of ethambutol (EMB) induced toxic optic neuropathy (TON) among diabetic and non-diabetic patients.Fifty patients under complete therapy of EMB for tuberculosis were included in the present study. Inclusion criteria for patients were to receive EMB everyday during treatment, a dose of 25 mg/kg for initial 2 months and 15 mg/kg during the rest of therapy period. We conducted color vision and visual acuity test for all patients.Fifteen out of fifty EMB induced TON patients, were found to be diabetic. Color vision and visual acuity test results were evaluated for diabetic and non-diabetic as well as twenty age matched controls. The results demonstrated a significant pattern of circulating biochemical markers between the studied groups. Data regarding hematological (RBC, p value = 0.02; Hemoglobin, p value = 0.02), hepatic (total bilirubin, p value = 0.01), renal (urea, p value = 0.03; creatinine, p value = 0.007), lipid (total cholesterol, p value = 0.01; total triglycerides, p value = 0.03) and antioxidative (superoxide dismutase, p value = 0.005; glutathione, p value = 0.02; catalase, p value = 0.02) profile showed a highly significant difference among the studied groups specially patients with diabetes. Malondialdehyde (MDA) level had gone significantly up in diabetic TON patients (p value = 0.02), in comparison to other antioxidants and vitamins (Vit). Vit-A, E, B1, B12 and Zinc seem to be playing a major role in the pathogenesis of TON, specially Vit-E and B1 surpassed all the antioxidants as having highly significant inverse relationships with MDA (MDA vs Vit-E, r = −0.676** and MDA vs Vit-B1, r = −0.724** respectively).We conclude that during the ethambutol therapy the decreased levels of Vit-E and Vit-B1 possibly play a role in the development of TON and may be used as therapeutic agents to lessen the deleterious effects of ethambutol. 相似文献
47.
Silvas J Prince Li Song Dan Qiu Joao V Maldonado dos Santos Chenglin Chai Trupti Joshi Gunvant Patil Babu Valliyodan Tri D Vuong Mackensie Murphy Konstantinos Krampis Dominic M Tucker Ruslan Biyashev Anne E Dorrance MA Saghai Maroof Dong Xu J Grover Shannon Henry T Nguyen 《BMC genomics》2015,16(1)
Background
Root system architecture is important for water acquisition and nutrient acquisition for all crops. In soybean breeding programs, wild soybean alleles have been used successfully to enhance yield and seed composition traits, but have never been investigated to improve root system architecture. Therefore, in this study, high-density single-feature polymorphic markers and simple sequence repeats were used to map quantitative trait loci (QTLs) governing root system architecture in an inter-specific soybean mapping population developed from a cross between Glycine max and Glycine soja.Results
Wild and cultivated soybean both contributed alleles towards significant additive large effect QTLs on chromosome 6 and 7 for a longer total root length and root distribution, respectively. Epistatic effect QTLs were also identified for taproot length, average diameter, and root distribution. These root traits will influence the water and nutrient uptake in soybean. Two cell division-related genes (D type cyclin and auxin efflux carrier protein) with insertion/deletion variations might contribute to the shorter root phenotypes observed in G. soja compared with cultivated soybean. Based on the location of the QTLs and sequence information from a second G. soja accession, three genes (slow anion channel associated 1 like, Auxin responsive NEDD8-activating complex and peroxidase), each with a non-synonymous single nucleotide polymorphism mutation were identified, which may also contribute to changes in root architecture in the cultivated soybean. In addition, Apoptosis inhibitor 5-like on chromosome 7 and slow anion channel associated 1-like on chromosome 15 had epistatic interactions for taproot length QTLs in soybean.Conclusion
Rare alleles from a G. soja accession are expected to enhance our understanding of the genetic components involved in root architecture traits, and could be combined to improve root system and drought adaptation in soybean.Electronic supplementary material
The online version of this article (doi:10.1186/s12864-015-1334-6) contains supplementary material, which is available to authorized users. 相似文献48.
A small open reading frame, termed 'pipo', is embedded in the P3 cistron of potyviruses. Currently, knowledge on pipo and its role(s) in the life cycle of potyviruses is limited. The P3 and helper-component proteinase (HC-Pro) cistrons of Soybean mosaic virus (SMV) harbour determinants affecting virulence on functionally immune Rsv1-genotype soybeans. Interestingly, a key virulence determinant of SMV on Rsv1-genotype soybeans (i.e. soybeans containing the Rsv1 resistance gene) that resides at polyprotein codon 947 overlaps both P3 and a pipo-encoded codon. This raises the question of whether PIPO or P3 is the virulence factor. To answer this question, the corresponding pipo of an avirulent and two virulent strains of SMV were studied by comparative genomics, followed by syntheses and analyses of site-directed mutants. Our data demonstrate that the virulence of SMV on Rsv1-genotype soybeans is affected by P3 and not the overlapping pipo-encoded protein. 相似文献
49.
50.
Fisher MJ Backer RT Husain S Hsiung HM Mullaney JT O'Brian TP Ornstein PL Rothhaar RR Zgombick JM Briner K 《Bioorganic & medicinal chemistry letters》2005,15(20):4459-4462
Substitution of the aryl sulfonamide moiety contained in MC4 agonist 1 with bicyclic heterocycles and aminotetralines produced compounds with MC4 activity. The heterocycles represent alternative privileged structures to that contained in 1. Compounds in which the polar group of the privileged structure was displayed in an endocyclic fashion were not as active as the parent agonist 1, while those with an exocyclic polar group afforded activity competitive with 1. 相似文献