Factors affecting Agrobacterium-mediated transformation in Hybanthus enneaspermus (L.) F. Muell

Ganeshan Sivanandhan,Chinnathambi Arunachalam,Venkatachalam Vasudevan,Gnanajothi Kapildev,Ali Alharbi Sulaiman,Natesan Selvaraj,Andy Ganapathi,임용표 한국식물생명공학회 2016 Plant biotechnology reports Vol.10 No.2

Agrobacterium tumefaciens-mediated transformation system was established for Hybanthus enneaspermus using leaf explants with the strain LBA4404 harbouring pCAMBIA 2301 carrying the nptII and gusA genes. Sensitivity of leaf explants to kanamycin was standardized (100 mg/l) for screening the transgenic plants. Transformation parameters (OD, virulence inducer, infection time, co-cultivation period, bactericidal antibiotics, etc.) influencing the gene transfer and integration were assessed in the present investigation. Fourteen-day precultured explants were subjected with Agrobacterium strain LBA4404. Optimized parameters such as culture density of 0.5 OD600, infection time of 6 min, AS concentration of 150 lM with 3 days co-cultivation revealed maximum transformation efficiency based on GUS expression assay. The presence of gusA in transgenics was confirmed by polymerase chain reaction and Southern blotting analysis. The present transformation experiment yielded 20 shoots/explant with higher transformation efficiency (28 %). The protocol could be used to introduce genes for trait improvement as well as for altering metabolic pathway for secondary metabolites production.

Design and Realization of Ultra Gain Boost Seven Level Inverter for Solar PV System

Sellappa Gounder Palanisamy,Chinnathambi Govindaraju 대한전기학회 2022 Journal of Electrical Engineering & Technology Vol.17 No.2

A new triple gain boost seven-level inverter is proposed for solar photo voltaic (PV) system suitable for standalone and grid-connected operations. The system is developed with a boost cascaded two-stage confi guration. The principal stage comprises of a high gain DC–DC converter to boost and normalise the input DC voltage with a single switch high gain converter (SSHGC), and the subsequent stage comprises of new multilevel inverter (MLI) topology with triple voltage gain to produce seven level AC. Proposed SSHGC is suitable for a wide conversion range. The switched capacitor techniques were employed to gain the voltage in MLI. The maximum voltage gain of the DC–DC converter is twelve and the voltage gain of the MLI is three, the resultant voltage DC–DC–AC is achieved up to 36. Modifi ed Perturb and Observe (P&O) based maximum power point tracking (MPPT) algorithm is applied in SSHGC to achieve maximum power utilisation in PV module and sinusoidal pulse width modulation (SPWM) is realistic in MLI control. A prototype model of 200 Watts is developed to analyze the proposed system. The overall converter system effi ciency reaches up to 92% with a total harmonics distortion (THD) of 0.18%

Differential Responses of Azolla microphylla Kaulf and Azolla filiculoides Lam. to Lead Nitrate

Muthukumaras, Eyini wamy,Devi, Natesan Anjana,Pothiraj, Chinnathambi,Jayakumar, Muthukrishnan,Kil, Bong-Seop 한국식물학회 2000 Journal of Plant Biology Vol.43 No.1

The aquatic fern Azolla is used as a green manure for rice production systems in warm temperate and tropical regions throughout the world. We used lead nitrate in nutrient media to assess the tolerance/response of two Azolla microphylla and Azolla filiculoides to heavy metals. While both species showed negative responses in growth with an increase in lead concentrations, They were distinctly different in their tolerance for higher concentration of the heavy metal. This was apparent in their growth and biochemical characteristics. A microphylla was more tolerant of the higher concentrations of lead nitrate (25 and 50ppm), whereas A. filiculoides had a higher rate of lead uptake.

NF-κB in cancer therapy.

Li, Feng,Zhang, Jingwen,Arfuso, Frank,Chinnathambi, Arunachalam,Zayed, M E,Alharbi, Sulaiman Ali,Kumar, Alan Prem,Ahn, Kwang Seok,Sethi, Gautam Springer-Verlag 2015 Archives of toxicology Vol.89 No.5

<P>The transcription factor nuclear factor kappa B (NF-kappa B) has attracted increasing attention in the field of cancer research from last few decades. Aberrant activation of this transcription factor is frequently encountered in a variety of solid tumors and hematological malignancies. NF-kappa B family members and their regulated genes have been linked to malignant transformation, tumor cell proliferation, survival, angiogenesis, invasion/metastasis, and therapeutic resistance. In this review, we highlight the diverse molecular mechanism(s) by which the NF-kappa B pathway is constitutively activated in different types of human cancers, and the potential role of various oncogenic genes regulated by this transcription factor in cancer development and progression. Additionally, various pharmacological approaches employed to target the deregulated NF-kappa B signaling pathway, and their possible therapeutic potential in cancer therapy is also discussed briefly.</P>

Cardamonin represses proliferation, invasion, and causes apoptosis through the modulation of signal transducer and activator of transcription 3 pathway in prostate cancer

Zhang, J.,Sikka, S.,Siveen, K. S.,Lee, J. H.,Um, J. Y.,Kumar, A. P.,Chinnathambi, A.,Alharbi, S. A.,Rangappa, K. S. Springer Science + Business Media 2017 Apoptosis Vol.22 No.1

<P>The pleiotropic transcription factor, signal transducer and activator of transcription 3 (STAT3) is often aberrantly activated in a wide variety of cancers and plays a pivotal role in tumor initiation, promotion and progression. Targeting deregulated STAT3 activation by small molecule inhibitors is generally considered as an important therapeutic strategy. Hence, in the present study, we evaluated the potential of cardamonin (CD), a 2',4'-dihydroxy-6'-methoxychalcone, to modulate STAT3 activation in prostate cancer (PC) cells and found that this chalcone can indeed exhibit significant anticancer effects through negatively regulating STAT3 activation by diverse molecular mechanism(s). CD suppressed STAT3 phosphorylation, nuclear translocation and DNA binding ability in PC cells. Computational modeling revealed that CD can bind directly to the Src Homology 2 domain of STAT3 and also effectively inhibit its dimerization. CD was also found to significantly reduce the migratory/invasive potential of PC cells through the downregulation of various oncogenic proteins. Overall, the data indicates that the potential application of CD as a STAT3 blocker can mitigate both the growth and survival of PC cells.</P>

Resveratrol inhibits STAT3 signaling pathway through the induction of SOCS-1: Role in apoptosis induction and radiosensitization in head and neck tumor cells

Baek, S.H.,Ko, J.H.,Lee, H.,Jung, J.,Kong, M.,Lee, J.w.,Lee, J.,Chinnathambi, A.,Zayed, M.,Alharbi, S.A.,Lee, S.G.,Shim, B.S.,Sethi, G.,Kim, S.H.,Yang, W.M.,Um, J.Y.,Ahn, K.S. G. Fischer 2016 Phytomedicine Vol.23 No.5

<P>Background: Signal transducer and activator of transcription 3 (STAT3) is persistently activated in squamous cell carcinoma of the head and neck (SCCHN) and can cause uncontrolled cellular proliferation and division. Hypothesis: Thus, its targeted abrogation could be an effective strategy to reduce the risk of SCCHN. Resveratrol is known for its anti-cancer efficacy in a variety of cancer models. Study design: The effect resveratrol on STAT3 activation, associated protein kinases, phosphatases, cellular proliferation and apoptosis was investigated. Methods: We evaluated the effect of resveratrol on STAT3 signaling cascade and its regulated functional responses in SCCHN cells. Results: We found that HN3 and FaDu cells expressed strongly phosphorylated STAT3 on both tyrosine 705 and serine 727 residues as compared to other SCCHN cells. The phosphorylation was completely suppressed by resveratrol in FaDu cells, but not substantially in HN3 cells. STAT3 suppression was mediated through the inhibition of activation of upstream JAK2, but not of JAK1 and Src kinases. Treatment with the protein tyrosine phosphatase (PTP) inhibitor pervanadate reversed the resveratrol-induced down-regulation of STAT3, thereby indicating a critical role for a PTP. We also found that resveratrol induced the expression of the SOCS-1 protein and mRNA. Further, deletion of SOCS-1 gene by siRNA suppressed the induction of SOCS-1, and reversed the inhibition of STAT3 activation. Resveratrol down-regulated various STAT3-regulated gene products, inhibited proliferation, invasion, as well as induced the cell accumulation in the sub-G1 phase and caused apoptosis. Beside, this phytoalexin also exhibited the enhancement of apoptosis when combined with ionizing radiation treatment. Conclusion: Our results suggest that resveratrol blocks STAT3 signaling pathway through induction of SOCS-1, thus attenuating STAT3 phosphorylation and proliferation in SCCHN cells. (C) 2016 Elsevier GmbH. All rights reserved.</P>

Isorhynchophylline, a Potent Plant Alkaloid, Induces Apoptotic and Anti-Metastatic Effects in Human Hepatocellular Carcinoma Cells through the Modulation of Diverse Cell Signaling Cascades

Lee, Hanwool,Baek, Seung Ho,Lee, Jong Hyun,Kim, Chulwon,Ko, Jeong-Hyeon,Lee, Seok-Geun,Chinnathambi, Arunachalam,Alharbi, Sulaiman Ali,Yang, Woong Mo,Um, Jae-Young,Sethi, Gautam,Ahn, Kwang Seok MDPI 2017 INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES Vol.18 No.5

<P>Isorhynchophylline (Rhy) is an active pharmacological component of <I>Uncaria rhynchophylla</I> that has been reported previously to exert significant antihypertensive and neuroprotective effects. However, very little is known about its potential anti-cancer activities. This study was carried out to evaluate the anticancer effects of Rhy against various human carcinoma cell lines. We found that Rhy exhibited substantial cytotoxic effect against human hepatocellular carcinoma HepG2 cells when compared with other human carcinoma cell lines including those of lung, pancreas, prostate, head and neck, breast, multiple myeloma, brain and renal cell carcinoma. Rhy induced apoptosis as characterized by accumulation of cells in sub G1 phase; positive Annexin V binding; activation of caspase-8, -9, and -3; and cleavage of PARP (poly-ADP ribose polymerase). This effect of Rhy correlated with the down-regulation of various proteins that mediated cell proliferation, cell survival, metastasis, and angiogenesis. Moreover, cell proliferation, migration, and constitutive CXCR4 (C-X-C chemokine receptor type 4), MMP-9 (Matrix metallopeptidase-9), and MMP-2 expression were inhibited upon Rhy treatment. We further investigated the effect of Rhy on the oncogenic cell signaling cascades through phospho-kinase array profiling assay. Rhy was found to abrogate phospho-p38, ERK, JNK, CREB, c-Jun, Akt, and STAT3 signals, but interestingly enhanced phospho-p53 signal. Overall, our results indicate, for the first time, that Rhy could exert anticancer and anti-metastatic effects through regulation of multiple signaling cascades in hepatocellular carcinoma cells.</P>