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41.
Arnab Sarkar Ashikur Rahaman Ipsita Biswas Gopeswar Mukherjee Subhrangsu Chatterjee Shamee Bhattacharjee Deba Prasad Mandal 《Journal of cellular physiology》2020,235(10):7159-7172
Transforming growth factor β (TGFβ) is a prominent cytokine that promotes tumor progression by activating epithelial-to-mesenchymal transition (EMT). This study indicated that TGFβ exerted metastasis by inducing zinc finger E-box binding homeobox 1 (ZEB1) and a long noncoding RNA, LINC00273, expressions in A549 cells. Knocking down LINC00273 diminished TGFβ induced ZEB1 expression as well as metastasis. Mechanistically, LINC00273 acted as a molecular sponge of microRNA (miR)-200a-3p which liberate ZEB1 to perform its prometastatic functions. LINC00273 knockdown and miR200a3p mimic transfection of A549 cells were used for validating the link between TGFβ and LINC00273 induced metastasis. RNA pulldown and luciferase assay were performed to establish mir200a-3p-LINC00273 interaction. High expressions of LINC00273, TGFβ, and ZEB1 with concurrent low miR200a-3p expression had been verified in vivo and in patient samples. Overall, LINC00273 promoted TGFβ-induced lung cancer EMT through miR-200a-3p/ZEB1 feedback loop and may serve as a potential target for therapeutic intervention in lung cancer metastasis. 相似文献
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Machaela Palor Lenka Stejskal Piya Mandal Annasara Lenman María Pía Alberione Jared Kirui Rebecca Moeller Stefan Ebner Felix Meissner Gisa Gerold Adrian J. Shepherd Joe Grove 《The Journal of biological chemistry》2020,295(50):16931
CD81 plays a central role in a variety of physiological and pathological processes. Recent structural analysis of CD81 indicates that it contains an intramembrane cholesterol-binding pocket and that interaction with cholesterol may regulate a conformational switch in the large extracellular domain of CD81. Therefore, CD81 possesses a potential cholesterol-sensing mechanism; however, its relevance for protein function is thus far unknown. In this study we investigate CD81 cholesterol sensing in the context of its activity as a receptor for hepatitis C virus (HCV). Structure-led mutagenesis of the cholesterol-binding pocket reduced CD81–cholesterol association but had disparate effects on HCV entry, both reducing and enhancing CD81 receptor activity. We reasoned that this could be explained by alterations in the consequences of cholesterol binding. To investigate this further we performed molecular dynamic simulations of CD81 with and without cholesterol; this identified a potential allosteric mechanism by which cholesterol binding regulates the conformation of CD81. To test this, we designed further mutations to force CD81 into either the open (cholesterol-unbound) or closed (cholesterol-bound) conformation. The open mutant of CD81 exhibited reduced HCV receptor activity, whereas the closed mutant enhanced activity. These data are consistent with cholesterol sensing switching CD81 between a receptor active and inactive state. CD81 interactome analysis also suggests that conformational switching may modulate the assembly of CD81–partner protein networks. This work furthers our understanding of the molecular mechanism of CD81 cholesterol sensing, how this relates to HCV entry, and CD81''s function as a molecular scaffold; these insights are relevant to CD81''s varied roles in both health and disease. 相似文献
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Anumeha Shukla R. C. Mehrotra Nivedita Mandal Mahesh G. Thakkar 《Historical Biology》2013,25(8):970-977
The Kutch region of western India (Gujarat State) is today arid to semiarid and characterised by mostly ephemeral streams which carry water during the monsoon. The uneven distribution of rainfall and disturbed topography are the result of climate change during the Cenozoic period. Two fossil woods, namely Bauhinium palaeomalabaricum Prakash and Prasad (Fabaceae) and Ebenoxylon indicum Ghosh and Kazmi (Ebenaceae), are described from Kutch in order to provide insights into the palaeovegetation and palaeoclimate. Because the modern representatives of the present and previously described taxa from the same horizon are thermophilic in nature and grow in evergreen to deciduous forests, a warm and humid climate is interpreted. Furthermore, the finding of some mangrove taxa in the assemblage indicates the lagoonal to intertidal environment at the time of deposition. 相似文献
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Pratim Chakraborti Ayan Roy Sunanda Mandal Subhasish Mukhopadhyay 《Journal of biomolecular structure & dynamics》2013,31(11):2330-2346
Our environment is stressed with a load of heavy and toxic metals. Microbes, abundant in our environment, are found to adapt well to this metal-stressed condition. A comparative study among five Cupriavidus/Ralstonia genomes can offer a better perception of their evolutionary mechanisms to adapt to these conditions. We have studied codon usage among 1051 genes common to all these organisms and identified 15 optimal codons frequently used in highly expressed genes present within 1051 genes. We found the core genes of Cupriavidus metallidurans CH34 have a different optimal codon choice for arginine, glycine and alanine in comparison with the other four bacteria. We also found that the synonymous codon usage bias within these 1051 core genes is highly correlated with their gene expression. This supports that translational selection drives synonymous codon usage in the core genes of these genomes. Synonymous codon usage is highly conserved in the core genes of these five genomes. The only exception among them is C. metallidurans CH34. This genomewide shift in synonymous codon choice in C. metallidurans CH34 may have taken place due to the insertion of new genes in its genomes facilitating them to survive in heavy metal containing environment and the co-evolution of the other genes in its genome to achieve a balance in gene expression. Structural studies indicated the presence of a longer N-terminal region containing a copper-binding domain in the cupC proteins of C. metallidurans CH3 that helps it to attain higher binding efficacy with copper in comparison with its orthologs. 相似文献
46.
Sahabuddin Sarwardi Prashanta Kumar Mandal Santanu Ray 《Journal of biological physics》2013,39(4):701-722
A three-component model consisting on one-prey and two-predator populations is considered with a Holling type II response function incorporating a constant proportion of prey refuge. We also consider the competition among predators for their food (prey) and shelter. The essential mathematical features of the model have been analyzed thoroughly in terms of stability and bifurcations arising in some selected situations. Threshold values for some parameters indicating the feasibility and stability conditions of some equilibria are determined. The range of significant parameters under which the system admits different types of bifurcations is investigated. Numerical illustrations are performed in order to validate the applicability of the model under consideration. 相似文献
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We investigated the effect of elicitation on cell wall strengthening in eggplant roots caused by 6 elicitors viz., chitosan (CH), salicylic acid (SA), methyl jasmonate, methyl salicylate and vitamins B2 and B12. Analysis of phenolic metabolites from eggplant roots by HPLC revealed presence of 6 major cell wall-bound phenolic compounds. They were 4-hydroxybenzoic acid (4-HBA), vanillic acid (VA), 4-hydroxybenzaldehyde (4-HBAld), vanillin (VAN), 4-coumaric acid (4-CA) and ferulic acid (FA). In eggplant roots, the concentrations of FA, VA and 4-HBA were 188.71, 113.64 and 109.42 μg/g DW, respectively, and they were higher than those of 4-HBAld, VAN and 4-CA. When elicited roots were analyzed by HPLC, quantitative differences could be clearly discerned in the amount of the phenolic compounds. After 48 h post-elicitation (hpe) in the presence of CH, the increase in 4-HBA, 4-CA and FA contents in cell wall was 2.6-, 2.8- and 3.0-fold, respectively, compared with control. After 72 hpe, in the presence of SA, the increase in 4-HBA, 4-CA and FA levels was 3.5-, 2.9- and 3.8-fold, respectively, compared with the control. As the elicitors have specific receptors in plants, it may be possible to utilize CH and SA for inducing resistance against important diseases in eggplant. 相似文献
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