Development of doubled haploids from an elite <Emphasis Type="Italic">indica</Emphasis> rice hybrid (BS6444G) using anther culture

A total of 200 doubled haploids (DHs) were generated from an elite rice hybrid, ‘BS6444G’ for which an androgenic method was developed by manipulating the physical and chemical factors. The spike pretreated at 10?°C for 7–8 days was effective for callusing and green plant regeneration. The maximum callus frequency was achieved when the anthers cultured in N6 medium supplemented with 2.0 mg L^?1 2,4-diclorophenoxyacetic acid, 0.5 mg L^?1 6-benzylaminopurine and 3% maltose. Calli induced in N6 media also showed significant green shoot regeneration in MS medium supplemented with 0.5 mg L^?1 1-napthalene acetic acid, 0.5 mg L^?1 kinetin, 1.5 mg L^?1 benzylaminopurine and 3% sucrose producing 210 green plants. Assessment of the ploidy status showed 95.71% fertile diploids and 4.2% polyploids; no haploids were observed. A total of 38 sequence-tagged microsatellite (STMS) markers proved able to discriminate a heterozygote from all the 200 DHs. The DHs grown in the field showed significant variation for their agronomic traits. Comparison of traits with control indicates homogeneity within each DH line and significant variance of traits between DH lines. Nine DH lines produce higher grain yield than the hybrid parent which suggests the possibility of exploiting hybrid vigor in indica rice through the development of DH lines of high yielding hybrids.     

Japanese encephalitis virus differentially modulates the induction of multiple pro-inflammatory mediators in human astrocytoma and astroglioma cell-lines

Astrocytes become activated in response to many CNS pathologies. The process of astrocyte activation remains rather enigmatic and results in so-called reactive gliosis, a reaction with specific structural and functional characteristics. Astrocytes play a vital role in regulating aspects of inflammation and in the homeostatic maintenance of the CNS. However, the responses of different human astroglial cell-lines in viral encephalitis mediated inflammation are not well documented. We have shown that Japanese encephalitis virus (JEV) infection causes morphological and functional changes in astrocytic cell-lines. We have demonstrated that besides reactive oxygen species (ROS) JEV infection differentially regulated the induction pattern of IL-6, IL-1 beta and IL-8. IP-10, MCP-1, MIG and RANTES secretions in different astroglial cell-lines. The expression of different proteins such as astrocyte-specific glial fibrillary acidic protein (GFAP), the glutamate aspartate transporter/essential amino acid transporter-1 (GLAST/EAAT-1), glutamate transporter-1/essential amino acid transporter-2 (GLT-1/EAAT-2), Ceruloplasmin and Thioredoxin (TRX) expression level also differ in different human astrocyte cell-lines following infection.     

Overexpression of HVA1 gene from barley generates tolerance to salinity and water stress in transgenic mulberry (Morus indica)

Late embryogenesis abundant (LEA) proteins are members of a large group of hydrophilic proteins found primarily in plants. The barley hva1 gene encodes a group 3 LEA protein and is induced by ABA and water deficit conditions. We report here the over expression of hva1 in mulberry under a constitutive promoter via Agrobacterium-mediated transformation. Molecular analysis of the transgenic plants revealed the stable integration and expression of the transgene in the transformants. Transgenic plants were subjected to simulated salinity and drought stress conditions to study the role of hva1 in conferring tolerance. The transgenic plants showed better cellular membrane stability (CMS), photosynthetic yield, less photo-oxidative damage and better water use efficiency as compared to the non-transgenic plants under both salinity and drought stress. Under salinity stress, transgenic plants show many fold increase in proline concentration than the non-transgenic plants and under water deficit conditions proline is accumulated only in the non-transgenic plants. Results also indicate that the production of HVA1 proteins helps in better performance of transgenic mulberry by protecting membrane stability of plasma membrane as well as chloroplastic membranes from injury under abiotic stress. Interestingly, it was observed that hva1 conferred different degrees of tolerance to the transgenic plants towards various stress conditions. Amongst the lines analysed for stress tolerance transgenic line ST8 was relatively more salt tolerant, ST30, ST31 more drought tolerant, and lines ST11 and ST6 responded well under both salinity and drought stress conditions as compared to the non-transgenic plants. Thus hva1 appears to confer a broad spectrum of tolerance under abiotic stress in mulberry.     

New structures help the modeling of toxic amyloidbeta ion channels

The mechanism of amyloid toxicity is poorly understood and there are two schools of thought in this hotly debated field: the first favors membrane destabilization by intermediate-to-large amyloid oligomers, with consequent thinning and non-specific ion leakage; the second favors ion-specific permeable channels lined by small amyloid oligomers. Published results currently support both mechanisms. However, the amyloidbeta (Abeta) peptide has recently been shown to form a U-shaped 'beta-strand-turn-beta-strand' structure. This structure and the available physiological data present a challenge for computational biology--to provide candidate models consistent with the experimental data. Modeling based on small Abeta oligomers containing extramembranous N-termini predicts channels with shapes and dimensions consistent with experimentally derived channel structures. These results support the hypothesis that small Abeta oligomers can form ion channels. Molecular dynamics modeling can provide blueprints of 3D structural conformations for many other amyloids whose membrane association is key to their toxicity.     

Effect of Withania somnifera Dunal in ethanol-induced anxiolysis and withdrawal anxiety in rats

Withania somnifera (WS) or its psychotropic preparation is known to play a critical role in morphine, alcohol and benzodiazepines addiction. This study investigates the role of WS in acute ethanol and withdrawal from chronic ethanol consumption using elevated plus maze paradigm in rats. Acute administration of ethanol (1.5-2 g/kg, ip) triggered anxiolytic effect and withdrawal from prolonged ethanol (9% v/v ethanol, 15 days) consumption elicited enhanced behavioral despair (anxiety). Acute administration of WS (50 mg/kg, oral) potentiated the anxiolytic action of subeffective dose of ethanol (0.5 or 1 g/kg, ip). Moreover, the ethanol withdrawal anxiety was markedly antagonized in dose dependent manner by WS at 200 and 500 mg/kg or higher dose of ethanol (2.5 g/kg). However, co-administration of subeffective doses of WS (50 mg/kg, oral) and ethanol also attenuated withdrawal-induced anxiety due to chronic ethanol (9% v/v ethanol, 15 days) consumption. The results suggest the protective effect of WS in the management of ethanol withdrawal reactions.