ATP2, the essential P4-ATPase of malaria parasites, catalyzes lipid-dependent ATP hydrolysis in complex with a Cdc50 β-subunit

ABSTRACTEfficient mechanisms of lipid transport are indispensable for the Plasmodium malaria parasite along the different stages of its intracellular life-cycle. Gene targeting approaches have recently revealed the irreplaceable role of the Plasmodium-encoded type 4 P-type ATPases (P4-ATPases or lipid flippases), ATP2, together with its potential involvement as antimalarial drug target. In eukaryotic membranes, P4-ATPases assure their asymmetric phospholipid distribution by translocating phospholipids from the outer to the inner leaflet. As ATP2 is a yet putative transporter, in this work we have used a recombinantly-produced P. chabaudi ATP2, PcATP2, to gain insights into the function and structural organization of this essential transporter. Our work demonstrates that PcATP2 heterodimerizes with two of the three Plasmodium-encoded Cdc50 proteins: PcCdc50B and PcCdc50A, indispensable partners for most P4-ATPases. Moreover, the purified PcATP2/PcCdc50B complex catalyses ATP hydrolysis in the presence of phospholipids containing either phosphatidylserine, phosphatidylethanolamine or phosphatidylcholine head groups, and that this activity is upregulated by phosphatidylinositol 4-phosphate. Overall, our work provides the first study of the function and quaternary organization of ATP2, a promising antimalarial drug target candidate.

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FOSL1 Inhibits Type I Interferon Responses to Malaria and Viral Infections by Blocking TBK1 and TRAF3/TRIF Interactions

mBio ◽

10.1128/mbio.02161-16 ◽

2017 ◽

Vol 8 (1) ◽

Cited By ~ 15

Author(s):

Baowei Cai ◽

Jian Wu ◽

Xiao Yu ◽

Xin-zhuan Su ◽

Rong-Fu Wang

Keyword(s):

Immune Responses ◽

Drug Target ◽

Malaria Parasite ◽

Viral Infections ◽

Type I Interferon ◽

Innate Immune ◽

Type I ◽

Potential Drug Target ◽

Chimeric Mice

ABSTRACT Innate immune response plays a critical role in controlling invading pathogens, but such an immune response must be tightly regulated. Insufficient or overactivated immune responses may lead to harmful or even fatal consequences. To dissect the complex host-parasite interactions and the molecular mechanisms underlying innate immune responses to infections, here we investigate the role of FOS-like antigen 1 (FOSL1) in regulating the host type I interferon (IFN-I) response to malaria parasite and viral infections. FOSL1 is known as a component of a transcription factor but was recently implicated in regulating the IFN-I response to malaria parasite infection. Here we show that FOSL1 can act as a negative regulator of IFN-I signaling. Upon stimulation with poly(I:C), malaria parasite-infected red blood cells (iRBCs), or vesicular stomatitis virus (VSV), FOSL1 “translocated” from the nucleus to the cytoplasm, where it inhibited the interactions between TNF receptor-associated factor 3 (TRAF3), TIR domain-containing adapter inducing IFN-β (TRIF), and Tank-binding kinase 1 (TBK1) via impairing K63-linked polyubiquitination of TRAF3 and TRIF. Importantly, FOSL1 knockout chimeric mice had lower levels of malaria parasitemia or VSV titers in peripheral blood and decreased mortality compared with wild-type (WT) mice. Thus, our findings have identified a new role for FOSL1 in negatively regulating the host IFN-I response to malaria and viral infections and have identified a potential drug target for controlling malaria and other diseases. IMPORTANCE Infections of pathogens can trigger vigorous host immune responses, including activation and production of type I interferon (IFN-I). In this study, we investigated the role of FOSL1, a molecule previously known as a transcription factor, in negatively regulating IFN-I responses to malaria and viral infections. We showed that FOSL1 was upregulated and translocated into the cytoplasm of cells after stimulation for IFN-I production. FOSL1 could affect TRAF3 and TRIF ubiquitination and consequently impaired the association of TRAF3, TRIF, and TBK1, leading to inhibition of IFN-I signaling. In vivo experiments with FOSL1 knockout chimeric mice further validated the negative role of FOSL1 in IFN-I production and antimicrobial responses. This report reveals a new functional role for FOSL1 in IFN-I signaling and dissects the mechanism by which FOSL1 regulates IFN-I responses to malaria and viral infections, which can be explored as a potential drug target for disease control and management.

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Exploring Drug Targets in Isoprenoid Biosynthetic Pathway forPlasmodium falciparum

Biochemistry Research International ◽

10.1155/2014/657189 ◽

2014 ◽

Vol 2014 ◽

pp. 1-12 ◽

Cited By ~ 6

Author(s):

Tabish Qidwai ◽

Farrukh Jamal ◽

Mohd Y. Khan ◽

Bechan Sharma

Keyword(s):

Antimalarial Drug ◽

Metabolic Pathways ◽

Drug Target ◽

Drug Targets ◽

Malaria Parasite ◽

Biosynthetic Pathway ◽

Comprehensive Analysis ◽

Isoprenoid Biosynthesis ◽

Biosynthesis Pathway ◽

Novel Targets

Emergence of rapid drug resistance to existing antimalarial drugs inPlasmodium falciparumhas created the need for prediction of novel targets as well as leads derived from original molecules with improved activity against a validated drug target. The malaria parasite has a plant plastid-like apicoplast. To overcome the problem of falciparum malaria, the metabolic pathways in parasite apicoplast have been used as antimalarial drug targets. Among several pathways in apicoplast, isoprenoid biosynthesis is one of the important pathways for parasite as its multiplication in human erythrocytes requires isoprenoids. Therefore targeting this pathway and exploring leads with improved activity is a highly attractive approach. This report has explored progress towards the study of proteins and inhibitors of isoprenoid biosynthesis pathway. For more comprehensive analysis, antimalarial drug-protein interaction has been covered.

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Computational Studies of Substrate Transport and Specificity in a Phospholipid Flippase

10.1101/2020.06.24.169771 ◽

2020 ◽

Author(s):

Yong Wang ◽

Joseph A Lyons ◽

Milena Timcenko ◽

Bert L. de Groot ◽

Poul Nissen ◽

...

Keyword(s):

Atp Hydrolysis ◽

Head Group ◽

Outer Leaflet ◽

Type Iv ◽

Lipid Head Group ◽

Dynamics Simulations ◽

Phospholipid Distribution ◽

Phospholipid Transport ◽

P Type ◽

Insight Into

AbstractType-IV P-type ATPases are lipid flippases which help maintain asymmetric phospholipid distribution in eukaryotic membranes by using ATP hydrolysis to drive unidirectional translocation of phospholipid substrates. Recent Cryo-EM and crystal structures have provided a detailed view of flippases, and we here use molecular dynamics simulations of the yeast flippase Drs2p:Cdc50p in an outward open conformation to study the first steps of phospholipid transport. Our simulations show phospholipid binding to a groove and subsequent movement towards the centre of the membrane, and reveal a preference for phosphatidylserine lipids. We find that the lipid head group stays solvated in the groove while the lipid tails stay in the membrane during the (half) transport event. The flippase also induces deformation and thinning of the outer leaflet. Together, our simulations provide insight into substrate binding to lipid flippases and suggest that multiple sites and steps in the functional cycle contribute to substrate selectivity.

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The SERCA residue Glu340 mediates inter-domain communication that guides Ca2+ transport

10.1101/2020.06.22.165365 ◽

2020 ◽

Author(s):

Maxwell M. G. Geurts ◽

Johannes D. Clausen ◽

Bertrand Arnou ◽

Cedric Montigny ◽

Guillaume Lenoir ◽

...

Keyword(s):

Atp Hydrolysis ◽

Transmembrane Helices ◽

Tight Coupling ◽

Hydrogen Bonding Pattern ◽

Plasmic Reticulum ◽

Cytosolic Domains ◽

Dynamics Simulations ◽

P Type ◽

Intramolecular Communication

AbstractThe sarco(endo)plasmic reticulum Ca2+-ATPase (SERCA) is a P-type ATPase that transports Ca2+ from the cytosol into the SR/ER lumen, driven by ATP. This primary transport activity depends on tight coupling between movements of the transmembrane helices forming the two Ca2+ binding sites and of the cytosolic headpiece mediating ATP hydrolysis. We have addressed the molecular basis for this intramolecular communication by analyzing the structure and functional properties of the SERCA mutant E340A. The mutated Glu340 residue is strictly conserved among the P-type ATPase family of membrane transporters and is located at a seemingly strategic position at the interface between the phosphorylation domain and the cytosolic ends of five out of SERCA’s ten transmembrane helices. The mutant displays a marked slowing of the Ca2+-binding kinetics, and its crystal structure in the presence of Ca2+ and ATP analogue reveals a rotated headpiece, altered connectivity between the cytosolic domains and altered hydrogen bonding pattern around residue 340. Supported by molecular dynamics simulations, we conclude that the E340A mutation causes a stabilization of the Ca2+ sites in a more occluded state, hence displaying slowed dynamics. This finding underpins a crucial role of Glu340 in inter-domain communication between the headpiece and the Ca2+-binding transmembrane region.

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Targeting Protein Kinases in the Malaria Parasite: Update of an Antimalarial Drug Target

Current Topics in Medicinal Chemistry ◽

10.2174/156802612799362922 ◽

2012 ◽

Vol 12 (5) ◽

pp. 456-472 ◽

Cited By ~ 31

Author(s):

Veronica M. Zhang ◽

Marina Chavchich ◽

Norman C. Waters

Keyword(s):

Protein Kinases ◽

Antimalarial Drug ◽

Drug Target ◽

Malaria Parasite

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The evolution, metabolism and functions of the apicoplast

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2009.0273 ◽

2010 ◽

Vol 365 (1541) ◽

pp. 749-763 ◽

Cited By ~ 178

Author(s):

Liting Lim ◽

Geoffrey Ian McFadden

Keyword(s):

Plasmodium Falciparum ◽

Drug Development ◽

Drug Target ◽

Malaria Parasite ◽

Therapeutic Interventions ◽

Parasite Cell ◽

Metabolic Functions

The malaria parasite, Plasmodium falciparum , harbours a relict plastid known as the ‘apicoplast’. The discovery of the apicoplast ushered in an exciting new prospect for drug development against the parasite. The eubacterial ancestry of the organelle offers a wealth of opportunities for the development of therapeutic interventions. Morphological, biochemical and bioinformatic studies of the apicoplast have further reinforced its ‘plant-like’ characteristics and potential as a drug target. However, we are still not sure why the apicoplast is essential for the parasite's survival. This review explores the origins and metabolic functions of the apicoplast. In an attempt to decipher the role of the organelle within the parasite we also take a closer look at the transporters decorating the plastid to better understand the metabolic exchanges between the apicoplast and the rest of the parasite cell.

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Structural dynamics of P-type ATPase ion pumps

Biochemical Society Transactions ◽

10.1042/bst20190124 ◽

2019 ◽

Vol 47 (5) ◽

pp. 1247-1257 ◽

Cited By ~ 17

Author(s):

Mateusz Dyla ◽

Sara Basse Hansen ◽

Poul Nissen ◽

Magnus Kjaergaard

Keyword(s):

Structural Dynamics ◽

Single Molecule ◽

New Technologies ◽

Atp Hydrolysis ◽

Resonance Energy Transfer ◽

Resonance Energy ◽

Time Resolved ◽

Dynamics Simulations ◽

Types Of Information ◽

P Type

Abstract P-type ATPases transport ions across biological membranes against concentration gradients and are essential for all cells. They use the energy from ATP hydrolysis to propel large intramolecular movements, which drive vectorial transport of ions. Tight coordination of the motions of the pump is required to couple the two spatially distant processes of ion binding and ATP hydrolysis. Here, we review our current understanding of the structural dynamics of P-type ATPases, focusing primarily on Ca2+ pumps. We integrate different types of information that report on structural dynamics, primarily time-resolved fluorescence experiments including single-molecule Förster resonance energy transfer and molecular dynamics simulations, and interpret them in the framework provided by the numerous crystal structures of sarco/endoplasmic reticulum Ca2+-ATPase. We discuss the challenges in characterizing the dynamics of membrane pumps, and the likely impact of new technologies on the field.

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