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81.
Tiwari R Priyamvada Singh R Nainawatee HS Kumar R Tyagi BS Gupta RK Nagarajan S 《Indian journal of experimental biology》2002,40(3):309-313
Detection of 1Dx5 gene and presence of 1B/1R wheat rye translocation were studied in nineteen elite Indian wheat genotypes using AS-PCR and STS markers, respectively. Fifteen genotypes had 1B/1R translocation whereas ten showed presence of 1Dx5 gene. More than 50 per cent of the genotypes tested were found positive for both 1Dx5 and 1B/1R translocation. The results are in conformity with HMW glutenin SDS-PAGE profile for 1Dx5 and cytological observations for 1B/1R translocation. 相似文献
82.
83.
An improved micropropagation protocol has been developed for teak (Tectona grandis). Nodal explants placed on MS medium supplemented with 22.2 M benzylaminopurine and then serially transferred to fresh medium after 12, 24, 48 and 72 h gave maximum culture establishment (76.8%). Establishment was reduced when explants were retained in the initial culture medium longer than 12 h. Explants collected in May showed maximum (76.8%) response. Placement of the explants on MS medium supplemented with 22.2 M benzylaminopurine and 0.57 M indole-3-acetic acid resulted in the maximum average number of shoots. In vitro raised micro shoots were rooted ex vitro by dipping in indole-3-butyric acid (9.8 mM) for 2 min followed by planting in polyethylene pots containing a soil:vermiculite (1:1 v/v) mixture. This treatment resulted in 77.9% survival of the plantlets. They were weaned in a glasshouse and finally moved to an agro-net shade house. 相似文献
84.
Chen YG Ashok BT Liu X Garikapaty VP Mittelman A Tiwari RK 《Cell stress & chaperones》2003,8(3):242-248
85.
Identification of potent inhibitors of Helicoverpa armigera gut proteinases from winged bean seeds 总被引:2,自引:0,他引:2
Giri AP Harsulkar AM Ku MS Gupta VS Deshpande VV Ranjekar PK Franceschi VR 《Phytochemistry》2003,63(5):523-532
Dry mature seeds of winged bean (Psophocarpus tetragonolobus L., DC.) (WB) contain several proteinase inhibitors. Two-dimensional gel analysis of WB seed protein followed by activity visualization using a gel-X-ray film contact print technique revealed at least 14 trypsin inhibitors (TIs) in the range of 28-6 kD. A total of seven inhibitors (WBTI-1 to 7) were purified by heat treatment and gel filtration followed by elution from preparative native gels. Based on their biochemical characterization such as molecular mass, pI, heat stability, and susceptibility to inactivation by reducing agents, WBTI-1 to 4 are Kunitz type inhibitors while WBTI-5 to 7 are classified as Bowman-Birk type serine proteinase inhibitors. Although Kunitz type TIs (20-24 kD) of WB have been reported, the smaller TIs that belong to the Bowman-Birk type have not been previously characterized. Seven major TIs isolated from WB seed were individually assessed for their potential to inhibit the gut proteinases (HGP) of Helicoverpa armigera, a pest of several economically important crops, which produces at least six major and several minor trypsin/chymotrypsin/elastase-like serine proteinases in the gut. WBTI-1 (28 kD) was identified as a potent inhibitor of HGP relative to trypsin and among the other WBTIs; it inhibited 94% of HGP activity while at the same concentration it inhibited only 22% of trypsin activity. WBTI-2 (24 kD) and WBTI-4 (20 kD) inhibited HGP activity greater than 85%. WBTI-3,-5,-6 and-7 showed limited inhibition of HGP as compared with trypsin. These results indicate that WBTIs have different binding potentials towards HGP although most of the HGP activity is trypsin-like. We also developed a simple and versatile method for identifying and purifying proteinase inhibitors after two-dimensional separation using the gel-X-ray film contact print technique. 相似文献
86.
Pant HC Sharma RK Patel SH Shukla HR Mittal AK Kasiraj R Misra AK Prabhakar JH 《Theriogenology》2003,60(1):27-34
The objectives of this study were to determine the relationship of age and body weight to testicular development and to establish norms for breeding soundness evaluations of Murrah buffalo bulls. Testicular measurements of 133 Murrah buffalo bulls of various ages were recorded with a caliper and a tape. Semen was collected twice a week for 5 weeks from groups of bulls which were 25-36 (n=17), 37-48 (n=16), 49-60 (n=14), of >60 (n=10) months of age. After examining volume, sperm concentration, and progressive motility semen was diluted in Tris-citric acid-egg yolk-fructose extender and frozen in 0.5 ml French straws. Testicular measurements of buffalo bulls were lower than those recorded for European breeds of cattle bulls. Nevertheless, like cattle bulls, scrotal circumference was highly correlated with other testicular measurements. Also, it had a significant positive relationship with semen volume and sperm concentration per ejaculate. Average sperm output per week in order of increasing age group was 15.3, 18.2, 19.8 and 23.6 x 10(9). Corresponding values for sperm output per week per gram of testis were 59.1, 45.8, 41.1, 36.2 x 10(6) indicating a reduction in spermatogenesis per unit of testis with advancing age. Compared to European breeds, daily sperm output in Murrah bulls was nearly 45% lower, presumably due to their nearly 40% lower scrotal circumference than Holstein bulls of the same age. These results indicate that in buffalo, as in cattle, scrotal circumference is a useful indicator of potential sperm output and may serve as an important criterion for selecting young bulls as AI sires. 相似文献
87.
Jadhao SJ Kataria JM Deepak JN Verma KC Kataria RS Tiwari AK 《Indian journal of experimental biology》2000,38(2):186-188
A rapid method of ultracentrifugation pelleting of avian adenovirus (AAV) from small volume of chloroform treated infected cell culture fluid or allantoic fluid was adapted for isolation of adenoviral DNA. The viral DNA extracted from semipurified viruses was found to be intact on agarose gel and pure enough (A260/280 = 1.85-1.92) for restriction enzyme analysis. Restriction endonuclease analysis of Indian strain of AAV serotype 1, AAV serotype 4 (group I AAVs) and egg drop syndrome-76 (EDS-76) virus genomes (group III AAV) with Hind III enzyme differentiated these viruses. The AAV serotype 1 and serotype 4 strain exhibited identical Hind III profile to European viral strains belonging to same serotypes however, the EDS-76 virus gave similar but not identical profile. The calculated genomic lengths for AAV serotype 1 and EDS-76 virus were approximately found to be 33.9 and 44.4 Kb, respectively. 相似文献
88.
Chickpea Defensive Proteinase Inhibitors Can Be Inactivated by Podborer Gut Proteinases 总被引:4,自引:0,他引:4
Ashok P. Giri Abhay M. Harsulkar Vasanti V. Deshpande Mohini N. Sainani Vidya S. Gupta Prabhakar K. Ranjekar 《Plant physiology》1998,116(1):393-401
Developing chickpea (Cicer arietinum L.) seeds 12 to 60 d after flowering (DAF) were analyzed for proteinase inhibitor (Pi) activity. In addition, the electrophoretic profiles of trypsin inhibitor (Ti) accumulation were determined using a gel-radiographic film-contact print method. There was a progressive increase in Pi activity throughout seed development, whereas the synthesis of other proteins was low from 12 to 36 DAF and increased from 36 to 60 DAF. Seven different Ti bands were present in seeds at 36 DAF, the time of maximum podborer (Helicoverpa armigera) attack. Chickpea Pis showed differential inhibitory activity against trypsin, chymotrypsin, H. armigera gut proteinases, and bacterial proteinase(s). In vitro proteolysis of chickpea Ti-1 with various proteinases generated Ti-5 as the major fragment, whereas Ti-6 and -7 were not produced. The amount of Pi activity increased severalfold when seeds were injured by H. armigera feeding. In vitro and in vivo proteolysis of the early- and late-stage-specific Tis indicated that the chickpea Pis were prone to proteolytic digestion by H. armigera gut proteinases. These data suggest that survival of H. armigera on chickpea may result from the production of inhibitor-insensitive proteinases and by secretion of proteinases that digest chickpea Pis. 相似文献
89.
Nithya BabuRajendran Paaventhan Palasingam Kamesh Narasimhan Wenjie Sun Shyam Prabhakar Ralf Jauch Prasanna R. Kolatkar 《Nucleic acids research》2010,38(10):3477-3488
Smad1 is a downstream effector of the BMP signaling pathway that binds regulatory DNA to execute gene expression programs leading to, for example, the maintenance of pluripotency in mice. On the contrary, the TGF-β-activated Smad3 triggers strikingly different programs such as mesodermal differentiation in early development. Because Smad1 and Smad3 contain identical amino acids at the DNA contact interface it is unclear how they elicit distinctive bioactivities. Here, we report the crystal structure of the MH1 domain of Smad1 bound to a palindromic Smad binding element. Surprisingly, the DNA contact interface of Smad1 is drastically rearranged when compared to Smad3. The N-terminal helix 1 of Smad1 is dislodged from its intramolecular binding site and adopts a domain swapped arrangement with a symmetry-related molecule. As a consequence, helix 2 kinks away from the double helix disabling several key phosphate backbone interactions. Thermal melting analysis corroborates a decompacted conformation of Smad1 and DNA binding assays indicate a lower overall affinity of Smad1 to DNA but increased cooperativity when binding to palindromic DNA motifs. These findings suggest that Smad1 and Smad3 evolved differential qualities to assemble on composite DNA elements and to engage in co-factor interactions by remodeling their N-termini. 相似文献
90.
B. Santhosh Kumar Santosh K. Tiwari R. Saikant G. Manoj Amit Kunwar G. Sivaram Zakia Abid Adeel Ahmad K. Indira Priyadarsini Aleem A. Khan 《Journal of trace elements in medicine and biology》2010,24(4):263-270
Aim of the present study was to evaluate in vitro toxicity and in vivo antibacterial, anti-inflammatory, antiulcer, and antioxidant activities of two organoselenium compounds, selenocystine (SeCys) and ebselen (Ebs). The study was conducted in experimentally induced ulcers in rodent model infected with Helicobacter pylori (H. pylori). In vitro toxicological studies on normal spleenic lymphocytes revealed that SeCys and Ebs were non-toxic to the cells even at 100 μM concentration. Antibacterial activity was observed at 500 μg/mL concentration of either of the compounds against H. pylori. In vivo studies after treatment with SeCys and Ebs (500 μg/kg/day) resulted in significant reduction in ROS production and inhibition of lipid peroxidation in gastric tissue. The antioxidant and anti-inflammatory activities of both the compounds were also confirmed by their ability to lower GSH reduction, to induce the expression of antioxidant genes such as GPx-4, and MnSOD and to suppress inflammatory genes namely COX-2, TNF-α and TGF-β. In addition, the immunomodulatory activity of both the compounds was evident by enhance of the CD4 levels and maintenance of the IgG, IL-6 and IL-10 levels. Persistent treatment (500 μg/kg, for 28 days) with both the compounds showed considerable (p < 0.05) ulcer healing property supporting its role in gastro protection. In conclusion, the results of our study suggest that both SeCys and Ebs possess broad spectrum of activities without any potential toxicity. 相似文献