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21.
A subunit of molecular weight 18300 has been separated and isolated from seeds of Brassica campestris L. This subunit was cleaved by using cyanogen bromide, trypsin, Staphylococcus aureus V8 protease and chymotrypsin; the fragments obtained from enzymatlc and chemical cleavages were separated and isolated by polyacrylamide gel electrophoresis and gel filtration. The amino acid analyses were carried out. The complete amino acid sequence of the subunit containing 172 amino acid residues has been established by manual Edman method.  相似文献   
22.
Milk lipid is secreted by a unique process, during which triacylglycerol droplets bud from mammary cells coated with an outer bilayer of apical membrane. In all current schemes, the integral protein butyrophilin 1A1 (BTN) is postulated to serve as a transmembrane scaffold, which interacts either with itself or with the peripheral proteins, xanthine oxidoreductase (XOR) and possibly perilipin‐2 (PLIN2), to form an immobile bridging complex between the droplet and apical surface. In one such scheme, BTN on the surface of cytoplasmic lipid droplets interacts directly with BTN in the apical membrane without binding to either XOR or PLIN2. We tested these models using both biochemical and morphological approaches. BTN was concentrated in the apical membrane in all species examined and contained mature N‐linked glycans. We found no evidence for the association of unprocessed BTN with intracellular lipid droplets. BTN‐enhanced green fluorescent protein was highly mobile in areas of mouse milk‐lipid droplets that had not undergone post‐secretion changes, and endogenous mouse BTN comprised only 0.5–0.7% (w/w) of the total protein, i.e. over 50‐fold less than in the milk‐lipid droplets of cow and other species. These data are incompatible with models of milk‐lipid secretion in which BTN is the major component of an immobile global adhesive complex and suggest that interactions between BTN and other proteins at the time of secretion are more transient than previously predicted. The high mobility of BTN in lipid droplets marks it as a potential mobile signaling molecule in milk .  相似文献   
23.
These studies report the development of an efficient technique for large-scale cultivation of fast-growing hairy root culture systems for production of bioactive isoflavones. Trifolium pratense L. is an important source of pharmaceutically important isoflavones with immense health care applications. Trifolium pratense was transformed using different strains of Agrobacterium rhizogenes for hairy root induction and establishment of hairy root rhizoclones. Selected fast-growing rhizoclones of T. pratense were evaluated for their growth and isoflavone production. This study is the first report of stable production of isoflavones through successive culture passages from transformed hairy-root rhizoclones of T. pratense. One of the fast-growing hairy-root rhizoclones 2364A displayed significantly higher accumulation of all four pharmaceutically important isoflavones, 8.56 mg (gdw)?1 of daidzein, 2.45 mg (gdw)?1 of genistein, 15.23 mg (gdw)?1 of formononetin, and 1.10 mg (gdw)?1 of biochanin A, compared to other rhizoclones.  相似文献   
24.
25.
Plant and Soil - Plant growth promoting bacteria (PGPB) containing 1-aminocyclopropane-1-carboxylate (ACC) deaminase can play an important role in abiotic stress tolerance in plants, particularly...  相似文献   
26.
A new species of the genus Cirrhimuraena (Anguilliformes: Ophichthidae), Cirrhimuraena indica sp. nov., is described based on eight specimens collected from the Paradip (Odisha) and Petuaghat harbours (West Bengal) along the Bay of Bengal. The species is distinct in having the upper jaw fringed with 16–17 cirri before posterior nostril and 4–5 in between the anterior and posterior nostrils on the side; dorsal fin originates above the level of gill opening, predorsal length is 9.3–10.9 in total length; the head is relatively large, the length is 9.3–9.8 in total length; no infraorbital pores are observed between the nostrils; teeth are numerous, small, conical and in bands on each jaw; pores are present before the gill opening 10–11 and before anus 47–48; pectoral-fin length is 2.4–2.8 in head length; predorsal vertebrae are 8–10, pre-anal vertebrae 43–47 and total vertebrae 164–169. In the maximum likelihood tree analysis for COI gene, the new species belongs to the same clade as the other congener of Cirrhimuraena chinensis and is separated from the species morphologically and genetically.  相似文献   
27.
NAD(P)H/NRH:quinone oxidoreductases (NQO1 and NQO2) protect against oxidative stress and neoplasia. Cross-breeding of NQO1-/- with NQO2-/- mice generated double-knockout (DKO) mice. DKO mice were born normal yet showed myelogenous hyperplasia as observed in single-knockout mice. DKO mice also showed bronchial-associated lymphoid tissue (BALT) that increased in number and size with age. BALT was absent in wild-type and single-knockout mice. Further analysis demonstrated infiltration of neutrophils and macrophages in BALT and significant increases in the serum cytokines TNFalpha, IL-6, and IL-1beta and increased expression of iNOS and higher nitric oxide in lung macrophages. The development of BALT in DKO mice presumably led to the release of cytokines and higher lung macrophage activation, because histologically spleen, thymus, and blood cultures and urine analysis showed absence of infection. Additionally, the DKO mice upon exposure to hyperoxia demonstrated severe intra-alveolar edema and perivascular inflammation and massive infiltration with neutrophils, compared with wild-type mice. These results suggest that NQO1 and NQO2 combined protect mice against lung inflammation, BALT, and hyperoxic lung injury.  相似文献   
28.
Role of endothelin (ETA) receptors in neonatal morphine withdrawal   总被引:1,自引:0,他引:1  
Puppala BL  Bhalla S  Matwyshyn G  Gulati A 《Peptides》2006,27(6):1514-1519
We have previously demonstrated role of central endothelin (ET) receptors in neonatal morphine tolerance. The present study was conducted to investigate involvement of central ET receptors in neonatal rat morphine withdrawal. The aim was to determine activation of G-proteins coupled to opioid and ET receptors by morphine and ET ligands in neonatal rat brains during morphine withdrawal. Pregnant female rats were rendered tolerant to morphine by chronic exposure to morphine pellets over 7 days. Withdrawal was induced on day 8 by removal of pellets. Rat pups were delivered by cesarean section 24 h after pellet removal. G-protein stimulation induced by morphine; ET-1; ETA receptor antagonist, BMS182874; and ETB receptor agonist, IRL1620, was determined in the brain of neonatal rats undergoing morphine withdrawal by [35S]GTPgammaS binding assay. Morphine-induced maximal stimulation of G-protein in morphine withdrawal group (83.60%) was significantly higher compared to placebo control group (66.81%). EC50 value for ET-1-induced G-protein stimulation during morphine withdrawal (170.60 nM) was higher than control (62.5 nM). BMS182874, did not stimulate GTP binding in control but significantly increased maximal stimulation of G-proteins in morphine withdrawal (86.07%, EC50 = 31.25 nM). IRL1620-induced stimulation of G-proteins was similar in control and morphine withdrawal. The present findings indicate involvement of central ETA receptors in neonatal morphine withdrawal.  相似文献   
29.
Analysis of total nitrogen, chlorophyll content, ribulose-1,5-bisphosphate carboxylase/oxygenase activity and net photosynthesis rate was carried out on the leaves that support the developing pods in pigeon pea [ Cajanus cajan (L.) Millsp. cv. Prabhat] at several stages during pod filling. A continuous loss in all the above-mentioned parameters was observed during the course of pod development. When no pods were allowed to develop by continuous flower removal treatment, there was a considerable delay in loss of all these metabolic parameters. Excision of pods after their mid-development resulted not only in no further loss, but also in a significant recovery both of total nitrogen and of other investigated characteristics.  相似文献   
30.
Nef is an accessory viral protein that promotes HIV-1 replication, facilitating alterations in cellular pathways via multiple protein-protein interactions. The advent of proteomics has expanded the focus on better identification of novel molecular pathways regulating disease progression. In this study, nef was sequenced from randomly selected patients, however, sequence variability identified did not elicited any specific mutation that could have segregated HIV-1 patients in different stages of disease progression. To explore the difference in Nef functionality based on sequence variability we used proteomics approach. Proteomic profiling was done to compare the effect of Nef variants in host cell protein expression. 2DGE in control and Nef transfected SupT1 cells demonstrated several differentially expressed proteins. Fourteen protein spots were detected with more than 1.5 fold difference. Significant down regulation was seen in six unique protein spots in the Nef treated cells. Proteins were identified as Cyclophilin A, EIF5A-1 isoform B, Rho GDI 1 isoform a, VDAC1, OTUB1 and α-enolase isoform 1 (ENO1) through LC-MS/MS. The differential expression of the 6 proteins was analyzed by Real time PCR, Western blotting and Immunofluorescence studies with two Nef variants (RP14 and RP01) in SupT1 cells. There was contrasting difference between the effect of these Nef variants upon the expression of these six proteins. Downregulation of α-enolase (ENO1), VDAC1 and OTUB1 was more significant by Nef RP01 whereas Cyclophilin A and RhoGDI were found to be more downregulated by Nef RP14. This difference in Nef variants upon host protein expression was also studied through a site directed mutant of Nef RP01 (55AAAAAAA61) and the effect was found to be reversed. Deciphering the role of these proteins mediated by Nef variants will open a new avenue of research in understanding Nef mediated pathogenesis. Overall study determines modulation of cellular protein expression in T cells by HIV-1 Nef variants.  相似文献   
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