Plant genes and their expression

The transcription of protein encoding genes and their regulation in plant cells shows the signature of a typical eukaryotic system. The major outcome of research in this area is recognition of variability in components assembled to design constitutive or inducible promoters, including those constituting enhancers and boundary elements. Such cis-acting elements respond to diverse intrinsic and extrinsic signals to take care of the needs of sessile plants. While much remains to be defined about the basic transcription machinery in plants, it is expected to follow the pattern as deciphered in animals. At the same time, a large number of genes for regulatory proteins have been cloned leading to information about DNA binding domains, activation domains, nuclear localization signals and oligomerization sites. However, most of this information needs to be tested by experimentation. Availability of transgenic systems in plants and biotechnological needs have given impetus to research for designing tailor-made inducible/ repressible promoters and to manipulate plant processes by deploying transcription factors. While considerable progress has been made, much remains to be learned about the biochemical and molecular basis of regulation of plant gene expression

Spin dynamics and frequency dependence of magnetic damping study in soft ferromagnetic FeTaC film with a stripe domain structure

Perpendicular magnetic anisotropy (PMA) and low magnetic damping are the key factors for the free layer magnetization switching by spin transfer torque technique in magnetic tunnel junction devices. The magnetization precessional dynamics in soft ferromagnetic FeTaC thin film with a stripe domain structure was explored in broad band frequency range by employing micro-strip ferromagnetic resonance technique. The polar angular variation of resonance field and linewidth at different frequencies have been analyzed numerically using Landau-Lifshitz-Gilbert equation by taking into account the total free energy density of the film. The numerically estimated parameters Land\'{e} $g$-factor, PMA constant, and effective magnetization are found to be 2.1, 2$\times10^{5}$ erg/cm$^{3}$ and 7145 Oe, respectively. The frequency dependence of Gilbert damping parameter ($\alpha$) is evaluated by considering both intrinsic and extrinsic effects into the total linewidth analysis. The value of $\alpha$ is found to be 0.006 at 10 GHz and it increases with decreasing precessional frequency.Comment: 5 Pages, 6 Figures, Regular Submissio

ANTIFUNGAL ACTIVITY OF PIMENTA DIOICA (L.) MERRIL AN AROMATIC MEDICINAL TREE

Objective: To assess the antifungal activities of the extracts of leaves of Pimenta dioica against human pathogenic fungi and identify the class of phytochemical responsible for the biological activity.Methods: The shade dried, and powdered leaves of Pimenta dioica were subjected to polarity based solvent extraction by soaking. The extracts were dried in a rotary flash evaporator and subjected to antifungal activity assay against Candida albicans, Microsporum canis and M. gypseum, by disc diffusion method. Antifungal active petroleum ether extract was subjected to phytochemical analysis to identify the active compound. The extract was then subjected to Thin Layer Chromatography (TLC) and Bioautography, by agar overlay method. The fractions were collected by Preparative TLC method and subjected to antifungal activity assay by disc diffusion method. Further, the Libermann-Burchard test was conducted to detect the broad group of compounds responsible for the bioactivity.Results: Among the five extracts viz. petroleum ether, chloroform, ethyl acetate, methanol and aqueous, the petroleum ether extract showed significant antifungal activity against Microsporum canis (50 mm), Microsporum gypseum (60 mm) and Candida albicans (23 mm). Terpenoids, tannins and flavonoids were found to be the chief constituents of the petroleum ether extract. The TLC of the extract revealed 7 spots with the Rf values 0.37, 0.42, 0.45, 0.52, 0.59, 0.76, 0.96 with the solvent system of hexane and acetone (1:0.5). The bioautography assay revealed inhibitory activity in the spots at Rf values 0.52 and 0.59. These fractions obtained by preparative TLC also confirmed the same. The phytochemical analysis of the fractions on the TLC plate suggests that the compound is triterpene or steroid.Conclusion: The antifungal activity of Pimenta dioica and the bioactive phytochemical has been reported in the present study. Preliminary phytochemical analysis has indicated that the compounds are triterpenes or steroids. The results indicate that the active compounds are potential lead molecules for new antifungal drugs in the management of infectious fungi

The pressure-amorphized state in zirconium tungstate: a precursor to decomposition

In contrast to widely accepted view that pressure-induced amorphization arises due to kinetic hindrance of equilibrium phase transitions, here we provide evidence that the metastable pressure-amorphized state in zirconium tungstate is a precursor to decomposition of the compound into a mixture of simple oxides. This is from the volume collapse ΔV across amorphization, which is obtained for the first time by measuring linear dimensions of irreversibly amorphized samples during their recovery to the original cubic phase upon isochronal annealing up to 1000 K. The anomalously large ΔV of 25.7 ± 1.2% being the same as that expected for the decomposition indicates that this amorphous state is probably a precursor to kinetically hindered decomposition. A P–T diagram of the compound is also proposed

OsIAA1, an Aux/IAA cDNA from rice, and changes in its expression as influenced by auxin and light

The Aux/IAA class of genes are rapidly induced by exogenous auxins and have been characterized extensively from many dicot species like Arabidopsis, Glycine max and Pisum sativum. We report here the isolation and characterization of rice (Oryza sativa L. subsp. Indica) OsIAA1 cDNA as a monocot member of the Aux/IAA gene family. The predicted amino acid sequence of OsIAA1 corresponds to a protein of ca. 26 kDa, which harbors all four characteristic domains known to be conserved in Aux/IAA proteins. The conservation of these Aux/IAA genes indicates that auxins have essentially a similar mode of action in monocots and dicots. Northern blot analysis revealed that the OsIAA1 transcript levels decrease in the excised coleoptile segments on auxin starvation, and the level is restored when auxin is supplemented; the increase in OsIAA1 transcript level was apparent within 15 to 30 min of auxin application. Auxin-induced OsIAA1 expression appears to be correlated with the elongation of excised coleoptile segments. In light-grown rice seedlings, OsIAA1 is preferentially expressed in roots and basal segment of the seedling, whereas in the etiolated rice seedlings, the OsIAA1 transcripts are most abundant in the coleoptile. A comparative analysis in light- and dark-grown seedling tissues indicates that the OsIAA1 transcript levels decrease on illumination

Preliminary study on the length-weight relationship of Sacura boulengeri (Heemstra, 1973) from Indian waters

Sacura boulengeri (Heemstra, 1973) is a rare serranid fish (Subfamily: Anthiinae) having very distinct distribution in the western Indian Ocean. The rarity of the species is evident from earlier reports and, so far, no related studies on the species have been published except on taxonomy and distributional records. In the present investigation, the length-weight relationship of Sacura boulengeri was estimated to be W = 0.0777 × L2.690 (with 95% confidence intervals for b and r2). An analysis of the stomach contents revealed that sergestid shrimps and copepods were the major food items of the diet

First record of the Garman's lanternfish Diaphus garmani (Family: Myctophidae) from Indian waters

The myctophid Diaphus garmani is recorded for the first time from Indian waters. Three specimens (54-59 mm standard length) were collected from deep sea shrimp trawlers off Quilon, southwest coast of India, between 80 -110 N and 740-760 E, at depths from 250 to 450 m

Report of Potato grouper and Cloudy grouper in fishery landings at Mumbai

Grouper fishery of Maharashtra is dominated by Epinephelus diacanthus with occasional landing of E. bleekeri, E. malabaricus, E.coioides, E. areolatus, E. polylepis, E. morrhua, E. latifasciatus, E. epistictus, E. radiatus and Cephalopholis sonnerati. During the routine fishery survey at Sassoon Dock on 9th October 2016 a single specimen of Potato grouper Epinephelus tukula measuring 35 cm TL (1.7 kg) was observed in the landings of a trawler operated at a depth of 40 off Ratnagiri. Reports of E. tukula is rare from Indian coast and other reports are from Lakshadweep, Vizhinjam (Kerala), Grand Island (Goa), Muttom, Enayam (Tamil Nadu) coasts (Sluka and Lazarus, 2010 Marine Biodiversity Records 3:1-3). Potato grouper, is a widely distributed Indo-Pacific species, but sparsely known in their distribution range from Red Sea to Kenya and Australia. The name refers to the potatoshaped dark blotches on the body