In order to assess the functional roles of heat stress-induced class B-heat shock factors in Arabidopsis, we investigated T-DNA knockout mutants of AtHsfB1 and AtHsfB2b. Micorarray analysis of double knockout hsfB1/hsfB2b plants revealed as strong an up-regulation of the basal mRNA-levels of the defensin genes Pdf1.2a/b in mutant plants. The Pdf expression was further enhanced by jasmonic acid treatment or infection with the necrotrophic fungus Alternaria brassicicola. The single mutant hsfB2b and the double mutant hsfB1/B2b were significantly improved in disease resistance after A. brassicicola infection. There was no indication for a direct interaction of Hsf with the promoter of Pdf1.2, which is devoid of perfect HSE consensus Hsf-binding sequences. However, changes in the formation of late HsfA2-dependent HSE binding were detected in hsfB1/B2b plants. This suggests that HsfB1/B2b may interact with class A-Hsf in regulating the shut-off of the heat shock response. The identification of Pdf genes as targets of Hsf-dependent negative regulation is the first evidence for an interconnection of Hsf in the regulation of biotic and abiotic responses.

The first run of the LHC was successful in that it saw the discovery of the elusive Higgs boson, a particle that is consistent with the SM hypothesis. There are a number of excesses in Run 1 ATLAS and CMS results which can be interpreted as being due to the existence of another heavier scalar particle. This particle has decay modes which we have studied using LHC Run 1 data. Using a minimalistic model, we can predict the kinematics of these final states and compare the prediction against data directly. A statistical combination of these results shows that a best fit point is found for a heavy scalar having a mass of 272 +12 −9 GeV. This result has been quantified as a three sigma effect, based on analyses which are not necessarily optimized for the search of a heavy scalar. The smoking guns for the discovery of this new heavy scalar and the prospects for Run 2 are discussed.

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A Gram-negative, motile, rod-shaped and non-spore-forming bacterium was isolated from a soil sample collected from the area adjoining an India Pesticide Limited plant, Lucknow, India. Strain IPL18T was characterized on the basis of phenotypic and genotypic data. Based on 16SrRNA gene sequence analysis, this strain was shown to belong to genus Devosia, with highest sequence similarity of 97. The genus Devosia was first described by Nakagawa et al. In the course of screening of culturable microbial diversity from a hexachlorocyclohexane (HCH) dump site, soil samples collected from 0-20 cm depth from an India Pesticide Limited plant, Lucknow, India, were analysed and many bacterial strains were isolated. While most of the bacterial strains were sphingomonads, strain IPL18 T was found to belong to genus Devosia. This strain was further characterized by using a polyphasic approach. Based on the results of phylogenetic, genotypic, phenotypic and chemotaxonomic characterization, strain IPL18T represents a novel species of genus Devosia.The 16S rRNA gene was amplified by colony PCR using universal primers 27F (59-AGAGTTTGATCCTGGCTCAG-39) and 1492R (59-TACGGTTACCTTGTTACGACTT-39). The conditions used for PCR amplification were as follows: denaturation of the target DNA at 96 u C for 5 min, followed by 30 cycles consisting of denaturation at 96 uC for 1 min, primer annealing at 55 u C for 1 min and primer extension at 72 u C for 1.5 min. After the last cycle, final extension was done at 72 u C for 10 min. The amplified fragment of approximately 1.5 kb was separated by agarose gel electrophoresis and purified by using an E.Z.N.A. gel extraction kit (Omega Bio-Tek). The purified fragment was sequenced using various combinations of universal primer sets and sequencing was done with an ABI 3100 Avant Genetic analyser (Applied Biosystems) at the Department of Zoology, University of Delhi, Delhi, India.A nearly complete 16S rRNA gene sequence of 1394 nt was obtained for strain IPL18T . A standard nucleotidenucleotide BLAST search (Altschul et al., 1997) against the GenBank database using this sequence showed that strain IPL18 T belongs to genus Devosia, with maximum similarity to the 16S rRNA gene sequence of D. riboflavina DSM 7230 T . Phylogenetic analysis was then carried out to establish the position of strain IPL18T within the evolutionary radiation encompassed by genus Devosia. Nearly full-length 16S rRNA gene sequences of the species of the genus Devosia with validly published names were retrieved from the GenBank database at NCBI (http:// www.ncbi.nlm.nih.gov). The sequence of Rhizobium leguminosarum USDA 2370T was used as an outgroup. These sequences as well as that of strain IPL18T were aligned using the CLUSTAL_X program (version 1.81b; Thompson et al., 1997). The alignment was checked manually for Abbreviation: HCH, hexachlorocyclohexane.The GenBank/EMBL/DDBJ accession number for the 16S rRNA gene sequence of strain IPL18T is EF433462.

Evolution of differential regulatory mechanisms can lead to quite distinct physiological attributes. In the present study, we have identified one such regulatory schema that regulates osa-miR408 and responds differentially in drought-sensitive and -tolerant indica rice varieties. A comparison of the drought stress response in drought-sensitive (Pusa Basmati 1 and IR64) and drought-tolerant (Nagina 22 and Vandana) indica rice varieties revealed that, during drought stress, levels of miR408 transcript decrease significantly in sensitive cultivars, whereas they remain elevated in the tolerant cultivars. The trend is reflected in young seedlings, as well as in flag leaf and spikelets of adult plants (heading stage). Members of the plastocyanin-like protein family targeted by miR408 also show the inverse expression profile and thus accumulate at a lower level in tolerant cultivars during drought. Interestingly, some members of this family are implicated in maintaining the cellular redox state and spikelet fertility in Arabidopsis. An investigation of miR408 loci (including promoter) in all four cultivars did not reveal any significant sequence variation indicating an involvement of the upstream regulatory schema. Indeed, a similar variety-specific stress response was found in the Oryza sativa squamosa promoter-binding-like 9 transcription factor that regulates miR408 expression. We further demonstrate that drought-mediated induction of miR408 in Nagina 22 is regulated by [Ca 2+ ] cyt levels. However, [Ca 2+ ] cyt does not appear to regulate miR408 levels in Pusa Basmati 1, suggesting a variety-specific evolution of regulatory schema in rice.