The MC160 protein of the molluscum contagiosum virus dampens cGAS/STING-induced interferon-β activation.

Molluscum contagiosum virus (MCV) is a poxvirus that causes benign, persistent skin lesions. MCV encodes a variety of immune evasion molecules to dampen host immune responses. Two of these proteins are the MC159 and MC160 proteins.

A membrane receptor platform integrates cues for egress and invasion in blood forms and activation of transmission stages.

Critical events in the life cycle of malaria-causing parasites depend on cyclic guanosine monophosphate homeostasis by guanylyl cyclases (GCs) and phosphodiesterases, including merozoite egress or invasion of erythrocytes and gametocyte activation. These processes rely on a single GCα, but in the absence of known signaling receptors, how this pathway integrates distinct triggers is unknown. We show that temperature-dependent epistatic interactions between phosphodiesterases counterbalance GCα basal activity preventing gametocyte activation before mosquito blood feed.

Revisiting the Role of Toxoplasma gondii ERK7 in the Maintenance and Stability of the Apical Complex.

Toxoplasma gondii extracellular signal-regulated kinase 7 (ERK7) is known to contribute to the integrity of the apical complex and to participate in the final step of conoid biogenesis. In the absence of ERK7, mature parasites lose their conoid complex and are unable to glide, invade, or egress from host cells. In contrast to a previous report, we show here that the depletion of ERK7 phenocopies the depletion of the apical cap protein AC9 or AC10.

An Alveolata secretory machinery adapted to parasite host cell invasion.

Apicomplexa are unicellular eukaryotes and obligate intracellular parasites, including Plasmodium (the causative agent of malaria) and Toxoplasma (one of the most widespread zoonotic pathogens). Rhoptries, one of their specialized secretory organelles, undergo regulated exocytosis during invasion. Rhoptry proteins are injected directly into the host cell to support invasion and subversion of host immune function.

Assessing Rhoptry Secretion in T. gondii.

Rhoptries are key secretory organelles for Toxoplasma gondii invasion. Here, we describe how to assess the ability of T. gondii tachyzoites to secrete their rhoptry contents in vitro.

A lipid-binding protein mediates rhoptry discharge and invasion in Plasmodium falciparum and Toxoplasma gondii parasites.

Members of the Apicomplexa phylum, including Plasmodium and Toxoplasma, have two types of secretory organelles (micronemes and rhoptries) whose sequential release is essential for invasion and the intracellular lifestyle of these eukaryotes. During invasion, rhoptries inject an array of invasion and virulence factors into the cytoplasm of the host cell, but the molecular mechanism mediating rhoptry exocytosis is unknown. Here we identify a set of parasite specific proteins, termed rhoptry apical surface proteins (RASP) that cap the extremity of the rhoptry.

The Plasmodium berghei serine protease PbSUB1 plays an important role in male gamete egress.

The Plasmodium subtilisin-like serine protease SUB1 is expressed in hepatic and both asexual and sexual blood parasite stages. SUB1 is required for egress of invasive forms of the parasite from both erythrocytes and hepatocytes, but its subcellular localisation, function, and potential substrates in the sexual stages are unknown. Here, we have characterised the expression profile and subcellular localisation of SUB1 in Plasmodium berghei sexual stages.

A Knockout Screen of ApiAP2 Genes Reveals Networks of Interacting Transcriptional Regulators Controlling the Plasmodium Life Cycle.

A family of apicomplexa-specific proteins containing AP2 DNA-binding domains (ApiAP2s) was identified in malaria parasites. This family includes sequence-specific transcription factors that are key regulators of development. However, functions for the majority of ApiAP2 genes remain unknown.

The malarial serine protease SUB1 plays an essential role in parasite liver stage development.

Transmission of the malaria parasite to its vertebrate host involves an obligatory exoerythrocytic stage in which extensive asexual replication of the parasite takes place in infected hepatocytes. The resulting liver schizont undergoes segmentation to produce thousands of daughter merozoites. These are released to initiate the blood stage life cycle, which causes all the pathology associated with the disease.

Proteolytic activation of the essential parasitophorous vacuole cysteine protease SERA6 accompanies malaria parasite egress from its host erythrocyte.

The malaria parasite replicates within an intraerythrocytic parasitophorous vacuole (PV). The PV and host cell membranes eventually rupture, releasing merozoites in a process called egress. Certain inhibitors of serine and cysteine proteases block egress, indicating a crucial role for proteases.

Plasmodium subtilisin-like protease 1 (SUB1): insights into the active-site structure, specificity and function of a pan-malaria drug target.

Release of the malaria merozoite from its host erythrocyte (egress) and invasion of a fresh cell are crucial steps in the life cycle of the malaria pathogen. Subtilisin-like protease 1 (SUB1) is a parasite serine protease implicated in both processes. In the most dangerous human malarial species, Plasmodium falciparum, SUB1 has previously been shown to have several parasite-derived substrates, proteolytic cleavage of which is important both for egress and maturation of the merozoite surface to enable invasion.

[Migrants' health, the experience of a network providing access to healthcare].

Migrants form a heterogeneous population which requires specific medical-social care. Networks providing access to healthcare are one of the solutions enabling migrants to benefit from curative and preventative primary care.

c-Fos mediates angiotensin II-induced aldosterone production and protein synthesis in bovine adrenal glomerulosa cells.

Angiotensin II (AngII), potassium ion, and ACTH are the main factors controlling aldosterone biosynthesis in adrenal glomerulosa cells. AP-1 response elements for the immediate early gene products, c-Fos and c-Jun, have been identified, among others, in the promoter of the steroidogenic acute regulatory (StAR) protein gene, whose expression is acutely regulated by activators of aldosterone production. In bovine glomerulosa cells, AngII treatment led to a rapid and transient increase in c-fos mRNA expression, c-Fos protein expression, and c-Fos phosphorylation.