Genetic tranformation of cotyledon explants of cowpea (Vigna unguiculata L. Walp) using Agrobacterium tumefaciens

Mature de-embryonated cotyledons with intact proximal end of Vigna unguiculata were cultured on B5 basal medium containing varying concentrations of BAP. Thirty-six percent of the explants produced shoots on B5 medium supplemented with 8× 10^–6 M BAP. Cotyledon explants were pre-incubated for 24 h, inoculated with A. tumefaciens pUCD2614 carrying pUCD2340, co-cultivated for 48 h and transferred to hygromycin-B (25 mg/l) containing shoot induction medium. Approximately 15–19% of the explants produced shoots on the selection medium. The elongated shoots were subsequently rooted on B5 basal medium containing hygromycin. The transgenic plants were later established in pots. The presence of hpt gene in the transgenic plants was confirmed by Southern blot hybridization.Abbreviations BAP 6-Benzylaminopurine - 2,4-D 2,4-dichlorophenoxyacetic acid - hpt hygromycin phosphotransferase - IAA Indole-3-acetic acid - NAA 1-naphthaleneacetic acid     

Engineered selective plant male sterility through pollen‐specific expression of the EcoRI restriction endonuclease

Unintended gene flow from transgenic plants via pollen, seed and vegetative propagation is a regulatory concern because of potential admixture in food and crop systems, as well as hybridization and introgression to wild and weedy relatives. Bioconfinement of transgenic pollen would help address some of these concerns and enable transgenic plant production for several crops where gene flow is an issue. Here, we demonstrate the expression of the restriction endonuclease EcoRI under the control of the tomato pollen‐specific LAT52 promoter is an effective method for generating selective male sterility in Nicotiana tabacum (tobacco). Of nine transgenic events recovered, four events had very high bioconfinement with tightly controlled EcoRI expression in pollen and negligible‐to‐no expression other plant tissues. Transgenic plants had normal morphology wherein vegetative growth and reproductivity were similar to nontransgenic controls. In glasshouse experiments, transgenic lines were hand‐crossed to both male‐sterile and emasculated nontransgenic tobacco varieties. Progeny analysis of 16 000–40 000 seeds per transgenic line demonstrated five lines approached (>99.7%) or attained 100% bioconfinement for one or more generations. Bioconfinement was again demonstrated at or near 100% under field conditions where four transgenic lines were grown in close proximity to male‐sterile tobacco, and 900–2100 seeds per male‐sterile line were analysed for transgenes. Based upon these results, we conclude EcoRI‐driven selective male sterility holds practical potential as a safe and reliable transgene bioconfinement strategy. Given the mechanism of male sterility, this method could be applicable to any plant species.     

The glycoprotein toxin of Bacillus thuringiensis subsp. israelensis indicates a lectinlike receptor in the larval mosquito gut

The mosquito-active protein crystals produced by Bacillus thuringiensis subsp. israelensis contain covalently attached aminosugars which are critical for their larvicidal activity. The 50% lethal concentrations toward Aedes aegypti larvae were increased up to 10-fold by mild periodate treatment, up to 40-fold by forming the protein crystals in the presence of tunicamycin, and up to 7-fold by the presence during the mosquito bioassays of N-acetylglucosamine or its trimer, triacetylchitotriose. Periodate-treated crystals and crystals formed in the presence of tunicamycin had greatly reduced binding capacities for wheat germ agglutinin, an N-acetylglucosamine-specific lectin. These results suggest that the B. thuringiensis subsp. israelensis glycoprotein toxin binds to a lectinlike receptor in the larval mosquito gut. Furthermore, the distinct lectin-binding patterns exhibited by diptera-active versus lepidoptera-active B. thuringiensis crystals suggest that host specificity for the microbial insecticides is determined, in part, by the carbohydrate portion of their glycoprotein crystals.     

Fibrinogen Induces Microglia-Mediated Spine Elimination and Cognitive Impairment in an Alzheimer’s Disease Model

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Sodium Butyrate Ameliorates l‐Arginine‐Induced Pancreatitis and Associated Fibrosis in Wistar Rat: Role of Inflammation and Nitrosative Stress

Several reports indicated that histone deacetylases (HDACs) play a crucial role in inflammation and fibrogenesis. Sodium butyrate (SB) is a short‐chain fatty acid having HDAC inhibition potential. The present study aimed to evaluate the protective effect of SB against l ‐arginine (l ‐Arg)‐induced pancreatic fibrosis in Wistar rats. Pancreatic fibrosis was induced by twice intraperitoneal (i.p.) injections of 20% l ‐Arg (250 mg/100 g) at 2‐h interval on day 1, 4, 7, and 10, whereas SB (800 mg/kg/day) was administrated for 10 days. At the end of the study, biochemical estimations, histological alterations, DNA damage, and the expression of various proteins were evaluated. Posttreatment of SB decreased l ‐Arg‐induced oxidative and nitrosative stress, DNA damage, histological alterations, and fibrosis. Interestingly, posttreatment of SB significantly decreased the expression of α‐smooth muscle actin, interleukin‐1β, inducible nitric oxide synthase, and 3‐nitrotyrosine. The present study demonstrated that posttreatment of SB alleviates l ‐Arg‐induced pancreatic damage and fibrosis in rat.     

Design of Escherichia coli-Expressed Stalk Domain Immunogens of H1N1 Hemagglutinin That Protect Mice from Lethal Challenge

The hemagglutinin protein (HA) on the surface of influenza virus is essential for viral entry into the host cells. The HA1 subunit of HA is also the primary target for neutralizing antibodies. The HA2 subunit is less exposed on the virion surface and more conserved than HA1. We have previously designed an HA2-based immunogen derived from the sequence of the H3N2 A/HK/68 virus. In the present study, we report the design of an HA2-based immunogen from the H1N1 subtype (PR/8/34). This immunogen (H1HA0HA6) and its circular permutant (H1HA6) were well folded and provided complete protection against homologous viral challenge. Antisera of immunized mice showed cross-reactivity with HA proteins of different strains and subtypes. Although no neutralization was observable in a conventional neutralization assay, sera of immunized guinea pigs competed with a broadly neutralizing antibody, CR6261, for binding to recombinant Viet/04 HA protein, suggesting that CR6261-like antibodies were elicited by the immunogens. Stem domain immunogens from a seasonal H1N1 strain (A/NC/20/99) and a recent pandemic strain (A/Cal/07/09) provided cross-protection against A/PR/8/34 viral challenge. HA2-containing stem domain immunogens therefore have the potential to provide subtype-specific protection.     

Draft genome sequence of Staphylococcus aureus 118 (ST772), a major disease clone from India

We report the draft genome sequence of an ST772 Staphylococcus aureus disease isolate carrying staphylococcal cassette chromosome mec (SCCmec) type V from a pyomyositis patient. Our de novo short read assembly is ∼2.8 Mb and encodes a unique Panton-Valentine leukocidin (PVL) phage with structural genes similar to those of φ7247PVL and novel lysogenic genes at the N termini.     

Curcumin improves wound healing by modulating collagen and decreasing reactive oxygen species

Wound healing consists of an orderly progression of events that re-establish the integrity of the damaged tissue. Several natural products have been shown to accelerate the healing process. The present investigation was undertaken to determine the role of curcumin on changes in collagen characteristics and antioxidant property during cutaneous wound healing in rats. Full-thickness excision wounds were made on the back of rat and curcumin was administered topically. The wound tissues removed on 4th, 8th and 12th day (post-wound) were used to analyse biochemical and pathological changes. Curcumin increased cellular proliferation and collagen synthesis at the wound site, as evidenced by increase in DNA, total protein and type III collagen content of wound tissues. Curcumin treated wounds were found to heal much faster as indicated by improved rates of epithelialisation, wound contraction and increased tensile strength which were also confirmed by histopathological examinations. Curcumin treatment was shown to decrease the levels of lipid peroxides (LPs), while the levels of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), activities were significantly increased exhibiting the antioxidant properties of curcumin in accelerating wound healing. Better maturation and cross linking of collagen were observed in the curcumin treated rats, by increased stability of acid-soluble collagen, aldehyde content, shrinkage temperature and tensile strength. The results clearly substantiate the beneficial effects of the topical application of curcumin in the acceleration of wound healing and its antioxidant effect. Both the authors have contributed equally towards this paper.     

Alteration in haematocrit values and plasma protein fractions during the breeding cycle of female pigeons, Columba livia

Haematocrit measurements and plasma protein electrophoresis were carried out in female pigeons (Columba livia) during the breeding cycle. Non-laying birds showed higher (p < 0.001) haematocrit values than those involved in courtship and mating, nest-building, incubation and feeding and brooding. Significant differences in relative percentage of various plasma protein fractions were observed as a function of breeding. Haematocrit could be a useful index to the non-laying status of pigeons like that in chickens, Gallus domesticus.     

Effects of diallyl disulfide (DADS) on expression of apoptosis associated proteins in androgen independent human prostate cancer cells (PC-3)

Prostate cancer is a leading cause of death among the aging men. Surgical or radiotherapy is effective when the cancer is confined to the prostate gland but once the cancer spreads beyond the pelvis even chemotherapy and hormonal ablation therapy fails in curing this disease. Our previous studies have shown that diallyl disulfide (DADS) induces cell cycle arrest and also induces apoptosis in PC-3 cells. And now the present study is focused to see whether there is an activation of caspase cascade pathway. Hence, in the present study the apoptotic effect of DADS is studied by Western blot analysis of caspase-3, -9, -10 and Bcl-2, Bad, and Bax protein. The Apoptotic cells were assessed by Hoechst 33342 staining with 25 and 40 microM concentrations of DADS for 24 h. The results have shown that DADS at 25 and 40 microM concentrations has induced the activation of caspases. There is a significant increase in the expression of caspases (3, 9, and 10). The proapoptotic protein Bax has significantly increased at 40 microM of DADS treatment and there is significant increase of Bad protein at both the concentration. Bcl-2 protein has significantly decreased in DADS treated cells. Therefore, the present investigation serves as evidence that DADS may be a therapeutic drug in the treatment of prostate cancer.