Rickettsial Pathogen Perturbs Tick Circadian Gene to Infect the Vertebrate Host.

is a medically important tick that transmits several microbes to humans, including rickettsial pathogen . In nature, these ticks encounter several abiotic factors including changes in temperature, humidity, and light. Many organisms use endogenously generated circadian pathways to encounter abiotic factors.

Tick-Borne Flavivirus Inhibits Sphingomyelinase (SMase), a Venomous Spider Ortholog to Increase Sphingomyelin Lipid Levels for Its Survival in Ticks.

Our previous study showed that cells from medically important arthropods, such as ticks, secrete extracellular vesicles (EVs) including exosomes that mediate transmission of flavivirus RNA and proteins to the human cells. Understanding the molecular determinants and mechanism(s) of arthropod-borne flavivirus transmission via exosome biogenesis is very important. In this current study, we showed that in the presence of tick-borne Langat Virus (LGTV; a member of tick-borne encephalitis virus complex), the expression of arthropod SMase, a sphingomyelinase D (SMase D) that catalyzes the hydrolytic cleavage of substrates like sphingomyelin (SM) lipids, was significantly reduced in both ticks () and in tick cells ().

Arthropod transcriptional activator protein-1 (AP-1) aids tick-rickettsial pathogen survival in the cold.

Ixodes scapularis ticks transmit several pathogens to humans including rickettsial bacterium, Anaplasma phagocytophilum. Here, we report that A. phagocytophilum uses tick transcriptional activator protein-1 (AP-1) as a molecular switch in the regulation of arthropod antifreeze gene, iafgp.

Coordination of different ligands to copper(II) and cobalt(III) metal centers enhances Zika virus and dengue virus loads in both arthropod cells and human keratinocytes.

Unlabelled: Trace elements such as copper and cobalt have been associated with virus-host interactions. However, studies to show the effect of conjugation of copper(II) or cobalt(III) metal centers to thiosemicarbazone ligand(s) derived from either food additives or mosquito repellent such as 2-acetylethiazole or citral, respectively, on Zika virus (ZIKV) or dengue virus (serotype 2; DENV2) infections have not been explored. In this study, we show that four compounds comprising of thiosemicarbazone ligand derived from 2-acetylethiazole viz.

Anaplasma phagocytophilum infection modulates expression of megakaryocyte cell cycle genes through phosphatidylinositol-3-kinase signaling.

Anaplasma phagocytophilum, the agent of human granulocytic anaplasmosis infects neutrophils and other cells from hematopoietic origin. Using human megakaryocytic cell line, MEG-01, we show that expression of cell cycle genes in these cells are altered upon A. phagocytophilum infection.

Phytochemical investigation of crude methanol extracts of different species of Swertia from Nepal.

Background: The genus Swertia is reported to contain potent bitter compounds like iridoids, xanthones and c-glucoflavones that are known to heal many human disorders. In contrast to high ethnomedicinally valued Swertia chirayita, its other species have not been studied extensively, in spite of their common use in traditional medicinal system in Nepalese communities. So, the present study attempts to investigate the content of total polyphenols, flavonoids, antioxidant activity and estimate the rough content of amarogentin, swertiamarin and mangiferin from different species of Swertia from Nepalese Himalayas.