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Euphorbia helioscopia L. (Euphorbiaceae), is an important medicinal plant species of the Himalayan region. The species showed wide variability in its phenotypic traits under different environmental conditions. The purpose of this study was to determine the impact of elevational gradient on the morphological traits and reproductive features of the species. The plants grown in the Kashmir University Botanical Garden were more vigorous and taller than the plants of high-altitude sites. Principal component analysis (PCA) revealed that the habitat of KUBG and Kangan (Ganderbal) were comparatively facilitated the growth of E. helioscopia. The regression analysis showed a positive correlation between various morphological traits. Our attempted results highlighted an elaborated account of the variation of phenotypic traits and seed germination performance in response to different environmental conditions along an elevational gradient.

Bergenia ciliata (Haw.) Sternb. is an important medicinal plant of the Himalayan region. Phenotypic attributes of a particular plant species varies along different altitudes in order to adapt and to overcome the changeable and stressful conditions. A number of environmental factors such as mean temperature, precipitation, soil characteristics, radiation intensity etc. changes with altitudinal gradient and thereby affect the morphological pattern of a plant species. The present study was undertaken to reveal the impact of the elevational gradient and habitat variability on the morphological features of the selected species. Under different environmental conditions the species exhibited enormous variability in its phenotypic traits. The plants were shorter at high altitude site, Gulmarg while the plants of low altitude site, Kashmir University Botanical Garden (KUBG) were taller and more vigorous. A significant decrease in the plant height, inflorescence length, leaf length, leaf breadth and petiole length occurred with increasing altitude. Principal component analysis (PCA) revealed that the habitat of KUBG and Ferozpora (Tangmarg) proved relatively better for the growth of B. ciliata. The regression analysis revealed positive correlation between plant height and traits like inflorescence length, leaf length, leaf number and thus predicting a direct impact of plant height on other traits. Our findings present a comprehensive account on the variability of phenotypic characteristics, in relation to the environmental conditions of this valuable medicinal plant species.

Kashmir valley is located between the Pir Panjal and the Karakoram Range in the India. The valley is encircled by mountain ranges characterized by snow covered high mountain peaks. Kashmir is known for its scenic beauty throughout the world named as "paradise on earth." One of the main factors backing to this fame of Kashmir is its rich biodiversity corresponding with a wide variety of habitats. Agricultural growth is essential for any region to alleviate rural poverty, ensure food security and create job opportunities for people living in rural and urban areas. Traditionally, agriculture has been practicable and sustainable industry in the Kashmir. By tradition it has been the predominant sector in the Kashmir valley which supports around above 70 per cent of its population directly or indirectly is associated with agriculture and allied activities. The important features like topography, physiographic feature, diversity of habitat especially Karewas and elevation are the key elements which creates the difference between hill and plain areas. Hilly areas as generally offer a vast scope for the growers and cultivation of mixed crops like, cereals, pulses, oilseeds, Saffron, maize, vegetables. The most important and dominant feature of hill farming is the small holding, sloping marginal lands. This region has its own specific geo-climatic condition, which determine the cropping pattern and its productivity allied activities like horticulture, dairy development, fisheries, livestock and sericulture also play significant role in the agriculture sector.

MicroRNA 155 (miR-155) is an oncomir, generated as a noncoding RNA from the BIC gene whose promoter activity is mainly controlled via activation protein 1 (AP-1) and NF-κB transcription factors. We found that the expression levels of miR-155 and programmed cell death 4 (Pdcd4) exhibit inverse relationships in tongue cancer cells (SAS and AWL) and tumor tissues compared to their relationships in normal FBM cells and normal tongue tissues, respectively. In silico and in vitro studies with the 3' untranslated region (UTR) of Pdcd4 via luciferase reporter assays, quantitative PCR (qPCR), and Western blotting showed that miR-155 directly targets Pdcd4 mRNA and blocks its expression. Ectopic expression of Pdcd4 or knockdown of miR-155 in tongue cancer cells predominantly reduces AP-1-dependent transcriptional activity of the BIC promoter and decreases miR-155 expression. In this study, we demonstrate that miR-155 expression is modulated by a feedback loop between Pdcd4, AP-1, and miR-155 which results in enhanced expression of miR-155 with a consequent progression of tongue tumorigenesis. Further, miR-155 knockdown increases apoptosis, arrests the cell cycle, regresses tumor size in xenograft nude mice, and reduces cell viability and colony formation in soft-agar and clonogenic assays. Thus, the restoration of Pdcd4 levels by the use of molecular manipulation such as using a miR-155 sponge has an essential role in the therapeutic intervention of cancers, including tongue cancer.

miR-155 is an oncomir, generated as a non-coding RNA from BIC gene whose promoter activity is mainly controlled via AP-1 and NF-κB transcription factors. We found that the expression levels of miR-155 and Pdcd4 exhibit inverse relationship in tongue cancer cells (SAS and AWL) and tumor tissues compared to normal FBM cells and normal tongue tissues, respectively. Insilco and In-vitro studies with 3’UTR of Pdcd4 via luciferase reporter assays, qPCR and western blots show that miR-155 directly targets Pdcd4 mRNA and blocks its expression. Ectopic expression of Pdcd4 or knockdown of miR-155 in tongue cancer cells predominantly reduces AP-1 dependent transcriptional activity of BIC promoter and decreases miR-155 expression. In this study, we demonstrate that miR-155 expression is modulated by a feedback loop between Pdcd4, AP-1 and miR-155 which results in enhanced expression of miR-155 with a consequent progression of tongue tumorigenesis. Further, miR-155 knockdown increases apoptosis, arrests cell cycle, regresses tumor size in xenograft nude mice and reduces cell viability and colony formation in soft agar and clonogenic assays. Thus, the restoration of Pdcd4 levels by the use of molecular manipulation such as using miR-155 sponge have important role in the therapeutic intervention of cancers, including tongue cancer.

Pdcd4 (programmed cell death 4) has been demonstrated to be a tumor suppressor gene and is expressed at higher levels during apoptosis. PDCD4 is down regulated in a subset of oral cancers (tongue and buccal cavity) and an association between its down-regulation by miR-21 and tumorigenesis and invasion in oral carcinoma has been demonstrated. In this study we show that miR-155 directly targets PDCD4 in SAS (tongue squamous carcinoma) cells. We demonstrate a positive feedback loop between miR-155 expression and AP-1 dependent transcription through the down regulation of PDCD4. Analysis of miR-155 promoter (BIC) showed the presence of NF-κB and AP-1 (c-Jun and c-Fos) transcription factor binding sites and PDCD4 is known to inhibit AP-1 dependent transcription. Ectopic expression of PDCD4 in SAS cells drastically reduced the BIC promoter activity via inhibition of AP-1 dependent transcription and down regulated the levels of miR-155. We also generated the Lentiviral based miR-155 sponge stable cells to down regulate miR-155 in SAS cells, and found an increase in PDCD4 protein levels. The activity of BIC promoter was relatively low in miR-155 sponge stable cells compared to control sponge stable cells as analyzed by a dual luciferase reporter assay. We have also seen the reduced rate of proliferation in miR-155 sponge stable cells compared to control sponge stable cells. Thus our data show that miR-155 directly targets PDCD4 and consequently activates AP-1 dependent transcription in BIC promoter and increasing the levels of miR-155. Citation Format: shabir A. zargar, Devarajan Karunagaran. MicroRNA-155 directly targets PDCD4 and activates BIC promoter through AP-1 dependent transcription to replenish miR-155 expression in SAS cells. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3070. doi:10.1158/1538-7445.AM2015-3070