Biology subjects

singh, s.

Publications and source records attributed to singh, s..

14 recordsLinked to original sources

bioRxiv2026

Mosquito-directed PROTACs to block malaria transmission

The mosquito stage of the Plasmodium falciparum life cycle is an attractive target for intervention since it is crucial for the sexual reproduction and transmission of parasites to human host. Mosquito determinants crucial for parasite infection and growth pose as lucrative targets for transmission blockers. Owing to the fact that p38 MAPK has role in immune response and vector competence, we have evaluated the potential of PROTAC molecule (NR-7h) to degrade Anopheles stephensi p38 MAPK (Asp38 MAPK), a conserved serine/threonine kinase involved in stress reactions, midgut homeostasis, and parasite survival. PROTAC-mediated degradation of Asp38 MAPK led to the disrupted development of the parasite, suggesting its crucial function in vector competence. Furthermore, NR-7h-treated mosquitoes showed higher expression of immune genes such Rel-2, TEP1, APL1, and NOS, suggesting that p38 MAPK regulates host immunity in a way that promotes parasite persistence. PROTAC-mediated degradation of target proteins, provides a more persistent and resistance-proof therapeutic effect than traditional kinase inhibitors. Our findings establish PROTACs as a novel vector-targeted strategy for the development of endectocides to limit malaria transmission.

molecular biology↗

bioRxiv2025

Mosquito Ferritin: A Haem-Binding Iron Store Required for Egg Development and Targetable for Malaria Control

Iron metabolism is essential for both mosquito reproductive fitness and Plasmodium development within the vector, yet this axis remains insufficiently explored as a potential target for malaria control. Ferritin, the major iron-storage protein and a central regulator of iron homeostasis, has not previously been biochemically or functionally characterized in any hematophagous insect. Our computational and phylogenetic analyses reveal that mosquito ferritin represents a unique case, combining conserved iron-binding motifs with distinctive haem-coordinating residues that confer an exceptionally high haem-binding affinity exceeding that of bacterioferritin. In addition, through a screen of multiple iron chelators in Anopheles larvae, we identified potent candidates with potential utility for vector control. Together, these findings establish mosquito ferritin as an evolutionarily distinct and physiologically essential protein, and they highlight iron homeostasis as a promising dual-target axis for next-generation vector control strategies.

biochemistry↗

bioRxiv2025

Altiratinib Targets PRP4K in Theileria annulata, Disrupting RNA Processing and Inducing Apoptosis in Infected Cells

Tropical theileriosis, driven by Theileria annulata, poses a critical threat to livestock health, particularly in the face of rising resistance to buparvaquone, the primary and only treatment option. This study investigates the therapeutic potential and mechanistic actions of Altiratinib, a spliceosome-associated kinase inhibitor, in targeting T.annulata-infected bovine cells. Through bioinformatic and molecular docking analyses, Altiratinib was shown to selectively bind conserved catalytic motifs of PRP4K homologs in T. annulata (TA21325) and Theileria parva (TpMuguga_01g00303), with reduced affinity observed upon L715F mutation. In vitro assays confirmed potent anti-parasitic activity against both buparvaquone-sensitive and - resistant strains, while sparing uninfected peripheral blood mononuclear cells. Proteomic profiling revealed disruption of host and parasite RNA splicing and translation machinery. Altiratinib further induced G1-phase arrest, inhibited cMET-mediated signaling, and suppressed DNA synthesis. Additionally, it triggered oxidative stress, mitochondrial depolarization, and ROS-mediated DNA damage, culminating in p53 activation and caspase-9-driven intrinsic apoptosis. Downregulation of TaSP expression reinforced its selective targeting of parasite-infected cells. These findings highlight Altiratinibs promise as a directed therapeutic for tropical theileriosis and other piroplasm infections, offering a novel avenue to combat drug-resistant strains and meriting further preclinical evaluation. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=150 HEIGHT=200 SRC="FIGDIR/small/684341v1_ufig1.gif" ALT="Figure 1"> View larger version (50K): org.highwire.dtl.DTLVardef@eeeb81org.highwire.dtl.DTLVardef@1a795ecorg.highwire.dtl.DTLVardef@163b9cdorg.highwire.dtl.DTLVardef@3b52db_HPS_FORMAT_FIGEXP M_FIG C_FIG HighlightsO_LIAltiratinib disrupts spliceosomal and translational machinery in Theileria annulata-infected host cells by targeting PRP4K homologs, leading to impaired RNA processing, oxidative stress, and intrinsic apoptosis. C_LIO_LIDemonstrates potent efficacy against both drug-sensitive and Buparvaquone-resistant strains, validating its potential as a novel therapeutic strategy for overcoming resistance in tropical theileriosis. C_LIO_LIDual-target mechanism modulates parasite and host oncogenic pathways, including cMET signaling, revealing Altiratinibs repurposing potential as a broad-spectrum antiparasitic with anticancer-like activity. C_LI

microbiology↗

bioRxiv2025

Targeting Leishmania donovani Sphingosine Kinase 1 using PF-543 enhances immune response and limits parasite load

BackgroundSphingosine-1-phosphate (S1P) is a bioactive lipid mediator regulating apoptosis, proliferation, and immune responses. While S1Ps presence in Leishmania donovani phagolysosomes has been reported, the role of sphingosine kinases, especially SphK1, in parasite survival and host immune modulation remains underexplored. This study investigates the molecular and functional role of L. donovani SphK1 (LdSphK1) and evaluates the antileishmanial potential of PF-543, a specific SphK1 inhibitor. MethodsLdSphK1 and human SphK1 (rhSphK1) were cloned, expressed in E. coli, purified, and analyzed by SDS-PAGE. Enzymatic activity and inhibition by PF543 were assessed using NBD-S1P-based fluorometric assays. Protein-ligand interactions were analyzed using Microscale Thermophoresis (MST). Leishmania promastigotes overexpressing LdSphK1 were studied via confocal microscopy, and their viability and infectivity were assessed in vitro. THP-1 macrophages infected with L. donovani were treated with PF543 alone or with Amphotericin B and analyzed by MTT assay, RT-PCR, Giemsa staining, ELISA and immunoblotting. In vivo efficacy was tested in L. donovani-infected Swiss mice. ResultsrLdSphK1 ([~]102 kDa) and rhSphK1 ([~]50 kDa) were enzymatically active and significantly inhibited by PF-543. MST confirmed high-affinity binding of PF-543 (KD [~]29 microMolar). In L. donovani SphK1 overexpressor (LdSphKa) promastigotes, PF543 inhibited SphK1 activity and reduced parasite infectivity, more than in wildtype L. donovani promastigotes. Notably, PF543 treatment reduced parasite infectivity in vitro, lowered amastigote load by [~]40%, and promoted a pro-inflammatory cytokine shift ({uparrow}IL-12, {uparrow}TNF-, {downarrow}IL-10). Inhibition of ceramide synthesis and S1P supplementation revealed that S1P rescues ceramide-induced parasite death, implicating SphK1 in parasite survival. PF543 and Amphotericin B demonstrated synergistic anti-parasitic effects both in vitro and in vivo, with >90% reduction in parasite burden in mice. ConclusionPF543 is a potent inhibitor of SphK1, impairing parasite survival and modulating host immune responses. When combined with Amphotericin B, it offers a synergistic therapeutic strategy against visceral leishmaniasis, warranting further clinical exploration. Author SummaryLeishmaniasis, a neglected tropical disease, has limited available treatments and is becoming more resistant to medications. In this study, we explored the therapeutic potential of PF-543, a potent sphingosine kinase 1 (SphK1) inhibitor (demonstrated anticancer effects in various preclinical models) against Leishmania donovani. We successfully cloned and purified both Leishmania and human SphK1 proteins and confirmed PF-543 binding through biochemical and biophysical assays. Overexpression of LdSphK1 in parasites enhanced their survival and infectivity. In vitro, PF-543 treatment of infected macrophages decreased amastigote burden, shifted cytokine profiles towards a pro-inflammatory state, and enhanced host cell apoptosis. Notably, PF-543 acted synergistically with Amphotericin B, the current clinical drug, both in vitro and in vivo in Swiss mice, drastically lowering parasite burden. This study highlights the possibility of combination therapy and finds PF-543 to be a promising irresistible host-targeted antileishmanial drug. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=151 SRC="FIGDIR/small/652326v2_ufig1.gif" ALT="Figure 1"> View larger version (36K): org.highwire.dtl.DTLVardef@1926575org.highwire.dtl.DTLVardef@4305f4org.highwire.dtl.DTLVardef@3c10c7org.highwire.dtl.DTLVardef@171801e_HPS_FORMAT_FIGEXP M_FIG C_FIG

pathology↗

bioRxiv2024

Erythrocytic plasma membrane calcium ATPase (PMCA4b) variations mediate redox imbalance to determine artemisinin sensitivity in malaria

Artemisinin resistance in Plasmodium falciparum remains a major public health challenge for the ongoing malaria elimination programs. Till now, artemisinin resistance is linked with the variations in the genome of P. falciparum which are mainly clustered in the Pfkelch13 gene. Several studies reported artemisinin resistance in the malaria endemic areas without finding any evidence of genetic variation in parasite for this occurrence. This study interrogated whether host genetic variations have any association with artemisinin sensitivity of malaria parasite. We investigated the relationship of 1) genetic variations in the human ATP2B4 gene and 2) the resultant surface expression of plasma membrane calcium ATPase (PMCA4b) with the intraerythrocytic levels of calcium, reactive oxygen species (ROS) and the resistance towards artemisinin in the intraerythrocytic parasite. This study found negative correlation of PMCA4b expression level with intraerythrocytic calcium and ROS levels. Further in-vitro growth assays revealed that artemisinin sensitivity is reduced in the parasites growing within the RBCs having low PMCA4b and high oxidative stress. Overall, this study highlights the strong association of host PMCA4b in cellular calcium mediated redox imbalance, which significantly contributes to artemisinin resistance in malaria parasite. Hence, this is the first study to document the effect of host variations on artemisinin sensitivity of the parasite. We further emphasize that many redox modulating RBC polymorphisms that are prevalent in malaria endemic areas could influence artemisinin resistance and can serve as potential biomarkers for predicting therapeutic response. Thus, detailed population specific research may provide new insights for personalized malaria treatment and may inform future drug development strategies. SignificanceThe human host and malaria parasite share a closely interconnected relationship hence host variations could influence parasite drug resistance. This study demonstrates that reduced PMCA4b expression, the primary calcium efflux pump in RBCs, significantly increases the erythrocytic calcium and reactive oxygen species (ROS) levels, thereby decreasing the P. falciparum growth as well as artemisinin sensitivity. Many ROS inducing RBC polymorphisms, such as sickle cell, thalassemia, G6PD deficiency, PMCA4b variations etc. have emerged as strong malaria protective traits in several studies in malaria endemic areas. But these traits could also influence artemisinin resistance and can serve as potential biomarkers for predicting therapeutic response and highlights the importance of host erythrocytes oxidative microenvironment surveillance in monitoring antimalarial drug resistance.

microbiology↗

bioRxiv2024

Theileria annulata Infection Promotes p53 suppression, Genomic Instability and DNA deaminase APOBEC3H upregulation leading to cancer-like phenotype in host cells

Theileria annulata-infected host leukocytes display cancer-like phenotypes, though the precise mechanism is yet to be fully understood. The occurrence of cancer-like phenotypes in Theileria-infected leukocytes may be attributed to various factors, including genomic instability and acquired mutations, a crucial trait that underpins the genetic foundation of cancer. This paper presents WGS data and bioinformatic analyses to reveal point mutations and large-scale alterations in six clinically relevant T. annulata-infected cell lines. We identified 7867 exon-linked somatic mutations common to all cell lines, and cancer association analysis showed significant accumulation in oncogenes (FLT4, NOTCH2, MAP3K1, DAXX, FCGR2B, ROS1) and tumor suppressor genes (BARD1, KMT2C, GRIN2A, BAP1) implicated in established critical cancer processes. We demonstrated that a crizotinib-induced blockade of the ROS1 oncogenic protein, which harbored the most mutations, led to the death of infected leukocytes. This is consistent with the significant role of ROS1 in parasite-induced leukocyte transformation. In addition, we found somatic mutations in genes involved in genome instability and the DDR pathway. Our findings support the notion that ROS1 and Nutulin 3a are valid targets for intervention, and the suppression of TP53, a crucial tumor suppressor gene, may play a significant role in cell immortalization. We also show that upon infection with the parasite, bovine cells upregulate the expression of APOBEC3H, a DNA mutator likely responsible for the detected mutations. Our study highlights how T. annulata transforms leukocytes to gain selective advantage via mutation, and our observations could steer future research towards a mechanistic understanding of disease pathogenesis.

cell biology↗

bioRxiv2022

Human malaria parasite cold shock protein plays an essential role in asexual and sexual stage development and presents an excellent druggable target

Cold shock proteins are well characterized in bacteria, plants and humans, however there is no information on their existence and role in malaria parasite. Here, we have delineated the function of a novel cold shock protein of Plasmodium falciparum (Pf) which we have annotated PfCoSP. Our results show that recombinant PfCoSP has both DNA and RNA binding activity, and also interacts with alpha and beta tubulin of Pf. PfCoSP binds with RNA and alpha tubulin simultaneously to form a complex. Expression of PfCoSP was found during asexual blood stages and gametocyte stages of malaria parasite. PfCoSP expression up-regulates many folds upon cold treatment, suggesting its role during hypothermic cold shock. Interestingly, PfCoSP showed binding with human cold shock protein LIN28A inhibitor LI71 that also inhibits PfCSP -alpha/beta tubulin interactions. LI71 showed antimalarial activity against asexual blood stage and gametocyte stage suggesting its multi-stage, transmission-blocking potential. We propose that PfCoSP may form a workbench for translation during cold stress via its interactions with target mRNAs and the cytoskeleton protein tubulin.

molecular biology↗

bioRxiv2022

Sphingosine-1-phosphate regulates Plasmodium histone deacetylase activity and exhibits epigenetic control over cell death and differentiation

Histone deacetylases (HDACs) play a key role in cellular processes by the regulation of gene transcription. This study contributes a novel insight how Plasmodium falciparum HDAC (PfHDAC-1) is regulated by S1P produced by host erythrocyte SphK-1. The binding of S1P with endogenous nuclear extract PfHDAC-1 and recombinant PfHDAC-1 blocks their activity. A significant modulation in transcriptional regulation of P. falciparum HDAC regulated genes resulted upon inhibition of S1P production through blocking of hSphK-1 by clinical SphK-1 inhibitor PF-543. PF-543 led to profound decrease in S1P in the parasites nuclear fraction. The significant modulation of PfHDAC-1 regulated specific candidate genes related to gametocytogenesis, virulence and proliferation was observed in parasite treated with SphK-1 inhibitor, suggesting S1P targets PfHDAC-1 and participates in epigenetic regulation of these key cellular processes. The epigenetic modulation of parasite cell growth and differentiation by host provides a novel approach for the developmenthost-targeted therapeutics.

molecular biology↗

bioRxiv2022

Multistage and transmission-blocking tubulin targeting potent antimalarial discovered from the open access MMV Pathogen Box

Development of resistance to current antimalarial therapies remains a significant source of concern. To address this risk, new drugs with novel targets in distinct developmental stages of Plasmodium parasites are required. In our current work, we have targeted P. falciparum Tubulin (PfTubulin) proteins which represent some of the potential drug targets for malaria chemotherapy. Plasmodial Microtubules play a crucial role during parasite proliferation, growth, and transmission, which render them highly desirable targets for the development of next-generation chemotherapeutics. Towards this, we have evaluated the antimalarial activity of Tubulin targeting compounds received from the Medicines for Malaria Venture (MMV) "Pathogen Box" against the human malaria parasite, P. falciparum (including 3D7, RKL-9 (Chloroquine resistant) and R539T (Artemisinin resistant) strains). At nanomolar concentrations, filtered out compounds exhibited pronounced multistage antimalarial effects across the parasite life cycle, including intra-erythrocytic blood stages, liver stage parasites, gametocytes and ookinetes. Concomitantly, these compounds were found to impede male gamete ex-flagellation, thus showing transmission-blocking potential of these compounds. Target mining of these potent compounds, by combining in silico, biochemical and biophysical assays, implicated PfTubulin as their molecular target, which may possibly act by disrupting microtubule assembly dynamics by binding at the interface of -{beta}Tubulin-dimer. Further, promising ADME profile of the parent scaffold supported its consideration as a lead compound for further development. Thus, our work highlights the potential of targeting PfTubulin proteins in discovering and developing next-generation, multistage antimalarial agents for treating Multi-Drug Resistant (MDR) malaria parasites. GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=151 SRC="FIGDIR/small/488926v1_ufig1.gif" ALT="Figure 1"> View larger version (39K): org.highwire.dtl.DTLVardef@ae9713org.highwire.dtl.DTLVardef@40950forg.highwire.dtl.DTLVardef@1fa34f2org.highwire.dtl.DTLVardef@1aa1cae_HPS_FORMAT_FIGEXP M_FIG C_FIG

microbiology↗

bioRxiv2020

Metalloprotease Gp63 targeting novel glycoside exhibits potential antileishmanial activity

Visceral Leishmaniasis (VL) and its aggressive cutaneous exacerbation known as Post Kala-azar Dermal Leishmaniasis (PKDL) cause a huge disease burden in tropics and sub-tropic endemic zones worldwide. Contemporary treatment modalities have been associated with various complications. Encouraged from the recent marked antimalarial effects from plant derived glycosides; here we have chemically synthesized a library of diverse Glycoside derivatives (Gly 1-12) and evaluated their inhibitory efficacy against Ag83 strain of Leishmania donovani. In vitro activity of Glycoside-2 (Gly 2) on promastigote form of Ag83 strain, unravelled its prominent anti-leishmanial property with IC50 value of 1.13M. In-silico studies also unveiled the efficacy of Gly 2 to bind to the membrane surface of parasite. The toxic effect of Gly 2 causes necrosis like death in promastigote by abrogating its proliferation leading to imbalanced redox homeostasis by disruption of mitochondrial membrane potential. Additionally, Gly 2 treatment demonstrated increased susceptibility of parasites towards complement mediated lysis and displayed strong lethal effect on amastigote-macrophage infection model mimicking pathophysiological condition of body. This lead molecule was quite effective against the clinical on promastigotes form of PKDL strain BS12 with IC50 value of 1.97 M making it the most suitable drug so far which can target both VL and PKDL simultaneously. Based on the above experimental validations we narrowed our thoughts regarding the potent role of Gly 2 targeting surface protein of L. donovani such as Gp63, a zinc metalloprotease. Further analysis of structure activity relationship (SAR) of these glycoside derivatives, demonstrated exceptional binding affinity of Gly 2 towards Gp63, a zinc metalloprotease of L. donovani; with strong H-bond interactions of Gly 2 with catalytic domain in the -helix B region of Gp63. The strong confined interactions between Gly 2 and the target protein Gp63 in a physiologically relevant cellular environment was further assessed by Cellular Thermal Shift Assay (CETSA) which corroborated with our previous results. Taken together, this study reports the serendipitous discovery of glycoside derivative Gly 2 with enhanced leishmanicidal activity and proves to be novel chemotherapeutic prototype against VL and PKDL. HighlightsO_LIA novel glycoside derivative (Gly 2) targets Gp63 functioning in L. donovani promastigotes, resulting in its abrogated proliferation and severely detabilized redox homeostasis, leading to parasitic death. C_LIO_LIStructure activity relationship (SAR) analysis revealed exceptional ligandability of Gly 2 towards Gp63 catalytic domain both in silico and in Cellular Thermal Shift Assay (CETSA) based in vitro analysis. C_LIO_LIGly 2 treatment exhibited increased parasite susceptibility towards complement mediated lysis and reduced macrophage infection in vitro mimicking the pathophysiological conditions. C_LIO_LIGly 2 showed profound antileishmanial activity against the clinical isolates of Post Kala-azar Dermal Leishmaniasis (PKDL). C_LI

pharmacology and toxicology↗

bioRxiv2020

An insight into transcriptome of LlaNAC Gene Over- expressing Tobacco Plants

Here, we report a whole transcriptome analysis of LlaNAC gene (from Lepidium latifolium) containing transgenic tobacco line (NC10) and wild type (WT), to attain deeper knowledge into the downstream genes activated by the over-expressing transgene. Transcriptome sequencing of NC10 and WT samples generated huge data using Illumina platform. The maximum number of unigenes GO annotated were of Biological process (8988, 3209) followed by molecular function (5155, 2577) and cellular components (3826, 1583) for WT and NC10 samples respectively. KEGG Pathway analysis revealed the unigenes were enriched in different functional pathway categories. The unigenes whose products involved in carbohydrate metabolism, glycan metabolism, and secondary metabolites synthesis were more for NC10 library in comparison to WT. Greater variety of transcription factors were involved in transgenic than wild-type plants. Genes like, Copia-like retrotransposable element, Peroxidase 64-like, Peptidyl-prolyl cis-trans isomerise, Cytochrome P450, Lipoyl synthase, CBL-interacting serine/threonine-protein kinase 5-like etc. were found differentially expressed in both the samples. Promoter analysis of these differentially expressed genes have elements for defence and stress response, abscisic acid response, shoot specific expression and light response, etc. In summary this study reports the involvement of the overexpressed genes in the dual action of cold tolerance and biomass accumulation, as sugars participate in both of these activities of the cell.

molecular biology↗

bioRxiv2020

Role of RBC membrane protein palmitoylation in regulation of molecular topology and susceptibility to Plasmodium falciparum invasion

Squeezability of biconcave RBC raises a fundamental query, about, how it can restructure its bendable cytoskeleton for efficient micro-circulation. We report for the first time, the existence of dynamic palmitoylome in RBC composed of 118 palmitoylated proteins that reduced to 42 upon treatment with 2BP, a generic inhibitor of palmitoylation. In-depth analysis revealed that Semaphorin7A, CR1 and ABCB6, the known RBC receptors for P. falciparum were reduced to negligible in 2BP-treated RBCs, suggesting palmitoylation-dependent recruitment of parasite-specific receptors. Interestingly, Kell, a single disulphide-linked co-partner in Kell-Kx complex was undetected in 2BP-treated RBCs, while Kx remained intact. RBCs-blocked with anti-Kell antibody demonstrated signficant reduction in parasite invasion, thus suggesting it as a receptor proto-type for P. falciparum invasion. Finally, reduced expression of Kell in palmitoylated protein pool of sickle-cell RBC ghost, with its diminished surface representation in these RBCs, proposed Kell, as one of the novel receptor-prototype for P. falciparum invasion.

cell biology↗

bioRxiv2020

Development of novel anti-malarial from structurally diverse library of molecules, targeting plant-like Calcium Dependent Protein Kinase 1, a multistage growth regulator of P. falciparum

Upon Plasmodium falciparum merozoites exposure to low [K+] environment in blood plasma, there is escalation of cytosolic [Ca2+] which activates Ca2+-Dependent Protein Kinase 1 (CDPK1), a signaling hub of intra-erythrocytic proliferative stages of parasite. Given its high abundance and multidimensional attributes in parasite life-cycle, this is a lucrative target for desiging antimalarials. Towards this, we have virtually screened MyriaScreenII diversity collection of 10,000 drug-like molecules, which resulted in 18 compounds complementing ATP-binding pocket of CDPK1. In vitro screening for toxicity in mammalian cells revealed that these compounds are non-toxic in nature. Further, SPR analysis demonstrated differential binding affinity of these compounds towards recombinantly purified CDPK1 protein. Selection of lead compound 1 was performed by evaluating their inhibitory effects on phosphorylation and ATP binding activities of CDPK1. Further, in vitro biophysical evaluations by ITC and FS revealed that binding of compound 1 is driven by formation of energetically favorable non-covalent interactions, with different binding constants in presence and absence of Ca2+, and TSA authenticated stability of compound 1 bound CDPK1 complex. Finally, compound 1 strongly inhibited intra-erythrocytic growth of P. falciparum in vitro. Concievably, we propose a novel CDPK1-selective inhibitor, step towards developing pan-CDPK kinase inhibitors, prerequisite for cross-stage anti-malarial protection.

biochemistry↗

bioRxiv2019

Supression of Perforin-like Protein pores inhibit Plasmodium multistage-growth, transmission and erythrocyte senescence

The pore forming Plasmodium perforin like proteins (PPLP), expressed in all stages of the parasite life cycle are central drivers for host interactions critical for completion of parasite life cycle and high transmission rates. The high sequence similarity in the central membrane attack complex/ perforin (MACPF) domain and consequent functional overlaps defines them as an attractive target for the development of multi-stage antimalarials. Herein we evaluated the mechanism of pan active function of central, highly conserved region of PPLPs, MACPF domain (PMD) and inhibitory potential of specifically designed anti-PMD chemo. The E. coli expressed rPMD interacts with erythrocyte membrane and form pores of ~10.5 nm height and ~24.3 nm diameter leading to haemoglobin release and dextran uptake. The treatment with PMD induced erythrocytes senescence at 48 hours which can account for the physiological effect of disseminated PLPs in loss of circulating erythrocytes inducing anemia during malaria infection. The anti-PMD inhibitors effectively blocked intraerythrocytic growth by suppressing invasion and egress of merozoites and protecting against erythrocyte senescence. Moreover, these inhibitors also blocked the hepatic stage and transmission stage parasite development suggesting multi-stage and transmission-blocking potential of these inhibitors. Additionally, the erythrocyte senescence protective potential of PMD inhibitors can be used to occlude PPLPs mediated severe malarial anemia. Further these inhibitors can be developed with a potential to protect against severity of the disease.\n\nAuthor SummaryMalaria continues to be a major global health threat despite of several exciting improvements in the treatment and prevention of the disease. One of the major concerns in the development of therapy is the emergence of the drug resistance. But for the efficient treatment regime, targeting multiple stages including host and vector would serve as an ideal therapy. Perforin like proteins (PLPs) are eukaryotic pore forming proteins that are highly conserved in the apicomplexan parasites. These play crucial roles in entry and exit of parasites from the host cells and establish infection at multiple stages of Plasmodium spp. life cycle. Understanding the mechanism of pore formation by smaller, functional, pan-active scaffold of PLPs can serve as a target for development of cross stage protection. Here, using various biochemical, biophysical and pharmacological evidences, we validate the activity and characterize the pore formation of PLPs on erythrocytes. Further, our specifically designed inhibitors could restrict this pore formation and impede the exit/entry of the parasites. Moreover, these inhibitors could also exert multiple stage inhibition and rescue the uninfected erythrocytes from death. Together, this study highlights the mechanism of pore formation by PPLPs and evaluates their potential for the development of pan-active inhibitors to provide both symptomatic and transmission blocking cure for malaria.

molecular biology↗