First evidence of ethylene production by Fusarium mangiferae associated with mango malformation

Malformation is arguably the most crucial disease of mango (Mangifera indica L.) at present. It is receiving great attention not only because of its widespread and destructive nature but also because of its etiology and control is not absolutely understood. Recently, Fusarium mangiferae is found to be associated with mango malformation disease. There are indications that stress ethylene production could be involved in the disease. Here we have shown the first direct evidence of production of ethylene in pure culture of F. mangiferae obtained from mango. The study also revealed that all the isolates dissected from mango acquire morphological features of F. mangiferae showing most similarity to the features of species with accepted standard features. The isolates of F. mangiferae from mango were observed to produce ethylene in significant amounts, ranging from 9.28–13.66 n mol/g dry wt/day. The findings presented here suggest that F. mangiferae could contribute to the malformation of mango by producing ethylene and probably stimulating stress ethylene production in malformed tissue of mango. Ethylene might be produced through 2-oxoglutarate-dependent oxygenase-type ethylene-forming-enzyme (EFE) pathway in Fusarium sp, which needs to be investigated.     

Site-Specific Phosphorylation of the DNA Damage Response Mediator Rad9 by Cyclin-Dependent Kinases Regulates Activation of Checkpoint Kinase 1

The mediators of the DNA damage response (DDR) are highly phosphorylated by kinases that control cell proliferation, but little is known about the role of this regulation. Here we show that cell cycle phosphorylation of the prototypical DDR mediator Saccharomyces cerevisiae Rad9 depends on cyclin-dependent kinase (CDK) complexes. We find that a specific G2/M form of Cdc28 can phosphorylate in vitro the N-terminal region of Rad9 on nine consensus CDK phosphorylation sites. We show that the integrity of CDK consensus sites and the activity of Cdc28 are required for both the activation of the Chk1 checkpoint kinase and its interaction with Rad9. We have identified T125 and T143 as important residues in Rad9 for this Rad9/Chk1 interaction. Phosphorylation of T143 is the most important feature promoting Rad9/Chk1 interaction, while the much more abundant phosphorylation of the neighbouring T125 residue impedes the Rad9/Chk1 interaction. We suggest a novel model for Chk1 activation where Cdc28 regulates the constitutive interaction of Rad9 and Chk1. The Rad9/Chk1 complex is then recruited at sites of DNA damage where activation of Chk1 requires additional DDR–specific protein kinases.     

Role of alpha-melanocyte stimulating hormone (α-MSH) in modulating the molecular mechanism adopted by melanocytes of Bos indicus under UVR stress

Molecular and Cellular Biochemistry - Ultraviolet radiations (UVR) are responsible for a wide variety of acute and chronic effects on the animal skin. However, the effect of UVR-induced oxidative...     

SIVcpz cross-species transmission and viral evolution toward HIV-1 in a humanized mouse model

HIV-1 evolved from its progenitor SIV strains, but details are lacking on its adaptation to the human host. We followed the evolution of SIVcpz in humanized mice to mimic cross-species transmission. Increasing viral loads, CD4⁺ T-cell decline, and non-synonymous mutations were seen in the entire genome reflecting viral adaptation.     

Mimicking SIV chimpanzee viral evolution toward HIV-1 during cross-species transmission

HIV-1 evolved from SIV during cross-species transmission events, though viral genetic changes are not well understood. Here, we studied the evolution of SIVcpzLB715 into HIV-1 Group M using humanized mice. High viral loads, rapid CD4⁺ T-cell decline, and non-synonymous substitutions were identified throughout the viral genome suggesting viral adaptation.     

Heterologous overexpression of Nothapodytes foetida strictosidine synthase enhances levels of anti-cancer compound camptothecin in Ophiorrhiza rugosa

Plant Cell, Tissue and Organ Culture (PCTOC) - Nothapodytes foetida, an endangered tree of Indian origin, is a major source of the anti-cancer monoterpenoid indole alkaloid, camptothecin (CPT)....     

Chloro and bromo-pyrazole curcumin Knoevenagel condensates augmented anticancer activity against human cervical cancer cells: design,synthesis, in silico docking and in vitro cytotoxicity analysis

Abstract

With an endeavor to develop novel curcumin analogs as potential anti-cancer agents, we designed and synthesized a series of Knoevenagel condensates by clubbing pyrazole carbaldehydes at the active methylene carbon atom of the curcumin backbone. Molecular docking studies were carried out to target the proposed derivatives on human kinase β (IKKβ), a potential anti-cancer target. The chloro derivative displayed five hydrogen bond interactions with a docking score of ?11.874?kcal/mol higher than curcumin (docking score =??7.434?kcal/mol). This was supported by the fact that the propellant shaped derivatives fitted aptly into the binding pocket. Molecular simulations studies were also conducted on the lead molecule and the results figured out that the stable complexes were developed as the minimal deviations per residue of protein within the range of 0.11–0.92 Å. The screened compounds were synthesized, characterized and evaluated in vitro for cytotoxicity against cervical cancer cell line, HeLa using standard cell proliferation assay. Chloro derivative and bromo analog demonstrated IC₅₀ (half maximal inhibitory concentration) value of 14.2 and 18.6 µg/ml, respectively, significantly lower than 42.4 µg/ml of curcumin and higher than 0.008 µg/ml of paclitaxel. Induction of apoptosis was evaluated in the terms of cleavage of caspase-3 enzyme and they also exhibited 69.6 and 65.4% of apoptosis significantly higher than 19.9% induced by curcumin. In conclusion, chloro and bromo derivatives must be evaluated under a set of stringent in vitro and in vivo parameters for translating in to a clinically viable product.

Communicated by Ramaswamy H. Sarma     

Genetic and physiological relatedness of antagonistic Trichoderma isolates against soil borne plant pathogenic fungi

In this study, the in vitro potential of 42 Trichoderma spp. were evaluated against four isolates of soil borne phytopathogenic fungi viz., Rhizoctonia solani, Macrophomina sp., Sclerotium rolfsii and Pythium aphanidermatum in dual culture techniques and through production of volatile and non-volatile inhibitors. In vitro screening results showed that the proportion of isolates with antagonistic activities was highest for the S. rolfsii followed by R. solani, Macrophomina sp. and P. aphanidermatum, respectively. The isolates TNT1, TNP2 and TWP1 showed consistent results in volatile and non-volatile activity in vitro against any of the two pathogens tested. Based on genomic finger prints, potential isolates showed no particular correlation between the origin of the isolates and the Random Amplified Polymorphic DNA (RAPD) groups could not be established. However, the polymorphism shown by the isolates did not correlate to their level of antagonism. Whereas, in physiology studies using BIOLOG (microbial identification system), three groups were formed, one group consists with 14 different Trichoderma species and two groups with two isolates each comprised of only T. koningii and T. viride.