Cyclic GMP Balance Is Critical for Malaria Parasite Transmission from the Mosquito to the Mammalian Host

ABSTRACT Transmission of malaria occurs during Anopheles mosquito vector blood meals, when Plasmodium sporozoites that have invaded the mosquito salivary glands are delivered to the mammalian host. Sporozoites display a unique form of motility that is essential for their movement across cellular host barriers and invasion of hepatocytes. While the molecular machinery powering motility and invasion is increasingly well defined, the signaling events that control these essential parasite activities have not been clearly delineated. Here, we identify a phosphodiesterase (PDEγ) in Plasmodium, a regulator of signaling through cyclic nucleotide second messengers. Reverse transcriptase PCR (RT-PCR) analysis and epitope tagging of endogenous PDEγ detected its expression in blood stages and sporozoites of Plasmodium yoelii. Deletion of PDEγ (pdeγ−) rendered sporozoites nonmotile, and they failed to invade the mosquito salivary glands. Consequently, PDEγ deletion completely blocked parasite transmission by mosquito bite. Strikingly, pdeγ− sporozoites showed dramatically elevated levels of cyclic GMP (cGMP), indicating that a perturbation in cyclic nucleotide balance is involved in the observed phenotypic defects. Transcriptome sequencing (RNA-Seq) analysis of pdeγ− sporozoites revealed reduced transcript abundance of genes that encode key components of the motility and invasion apparatus. Our data reveal a crucial role for PDEγ in maintaining the cyclic nucleotide balance in the malaria parasite sporozoite stage, which in turn is essential for parasite transmission from mosquito to mammal. IMPORTANCE Malaria is a formidable threat to human health worldwide, and there is an urgent need to identify novel drug targets for this parasitic disease. The parasite is transmitted by mosquito bite, inoculating the host with infectious sporozoite stages. We show that cellular signaling by cyclic nucleotides is critical for transmission of the parasite from the mosquito vector to the mammalian host. Parasite phosphodiesterase γ is essential for maintaining cyclic nucleotide balance, and its deletion blocks transmission of sporozoites. A deeper understanding of the signaling mechanisms involved in transmission might inform the discovery of novel drugs that interrupt this essential step in the parasite life cycle.

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Maternally supplied S-acyl-transferase is required for crystalloid organelle formation and transmission of the malaria parasite

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1522381113 ◽

2016 ◽

Vol 113 (26) ◽

pp. 7183-7188 ◽

Cited By ~ 15

Author(s):

Jorge M. Santos ◽

Neuza Duarte ◽

Jessica Kehrer ◽

Jai Ramesar ◽

M. Cristina Avramut ◽

...

Keyword(s):

Plasmodium Berghei ◽

Malaria Parasite ◽

Mammalian Host ◽

Mosquito Vector ◽

Parasite Transmission ◽

Acyl Transferase

Transmission of the malaria parasite from the mammalian host to the mosquito vector requires the formation of adequately adapted parasite forms and stage-specific organelles. Here we show that formation of the crystalloid—a unique and short-lived organelle of the Plasmodium ookinete and oocyst stage required for sporogony—is dependent on the precisely timed expression of the S-acyl-transferase DHHC10. DHHC10, translationally repressed in female Plasmodium berghei gametocytes, is activated translationally during ookinete formation, where the protein is essential for the formation of the crystalloid, the correct targeting of crystalloid-resident protein LAP2, and malaria parasite transmission.

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Distinct Malaria Parasite Sporozoites Reveal Transcriptional Changes That Cause Differential Tissue Infection Competence in the Mosquito Vector and Mammalian Host

Molecular and Cellular Biology ◽

10.1128/mcb.00553-08 ◽

2008 ◽

Vol 28 (20) ◽

pp. 6196-6207 ◽

Cited By ~ 61

Author(s):

Sebastian A. Mikolajczak ◽

Hilda Silva-Rivera ◽

Xinxia Peng ◽

Alice S. Tarun ◽

Nelly Camargo ◽

...

Keyword(s):

Salivary Glands ◽

Malaria Parasite ◽

Transmembrane Protein ◽

Tissue Infection ◽

Mammalian Host ◽

Mosquito Vector ◽

Targeted Gene Deletion ◽

Transcriptional Changes ◽

Host Infection ◽

Genome Scale

ABSTRACT The malaria parasite sporozoite transmission stage develops and differentiates within parasite oocysts on the Anopheles mosquito midgut. Successful inoculation of the parasite into a mammalian host is critically dependent on the sporozoite's ability to first infect the mosquito salivary glands. Remarkable changes in tissue infection competence are observed as the sporozoites transit from the midgut oocysts to the salivary glands. Our microarray analysis shows that compared to oocyst sporozoites, salivary gland sporozoites upregulate expression of at least 124 unique genes. Conversely, oocyst sporozoites show upregulation of at least 47 genes (upregulated in oocyst sporozoites [UOS genes]) before they infect the salivary glands. Targeted gene deletion of UOS3, encoding a putative transmembrane protein with a thrombospondin repeat that localizes to the sporozoite secretory organelles, rendered oocyst sporozoites unable to infect the mosquito salivary glands but maintained the parasites' liver infection competence. This phenotype demonstrates the significance of differential UOS expression. Thus, the UIS-UOS gene classification provides a framework to elucidate the infectivity and transmission success of Plasmodium sporozoites on a whole-genome scale. Genes identified herein might represent targets for vector-based transmission blocking strategies (UOS genes), as well as strategies that prevent mammalian host infection (UIS genes).

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MRE11 Is Crucial for Malaria Parasite Transmission and Its Absence Affects Expression of Interconnected Networks of Key Genes Essential for Life

Cells ◽

10.3390/cells9122590 ◽

2020 ◽

Vol 9 (12) ◽

pp. 2590

Author(s):

David S. Guttery ◽

Abhinay Ramaprasad ◽

David J. P. Ferguson ◽

Mohammad Zeeshan ◽

Rajan Pandey ◽

...

Keyword(s):

Genome Stability ◽

Malaria Parasite ◽

Mosquito Vector ◽

Parasite Transmission ◽

Biological Processes ◽

Cluster Assembly ◽

Iron Sulfur Cluster ◽

Iron Sulfur ◽

Parasite Plasmodium ◽

Damage Response

The meiotic recombination 11 protein (MRE11) plays a key role in DNA damage response and maintenance of genome stability. However, little is known about its function during development of the malaria parasite Plasmodium. Here, we present a functional, ultrastructural and transcriptomic analysis of Plasmodium parasites lacking MRE11 during its life cycle in both mammalian and mosquito vector hosts. Genetic disruption of Plasmodium berghei mre11 (PbMRE11) results in significant retardation of oocyst development in the mosquito midgut associated with cytoplasmic and nuclear degeneration, along with concomitant ablation of sporogony and subsequent parasite transmission. Further, absence of PbMRE11 results in significant transcriptional downregulation of genes involved in key interconnected biological processes that are fundamental to all eukaryotic life including ribonucleoprotein biogenesis, spliceosome function and iron–sulfur cluster assembly. Overall, our study provides a comprehensive functional analysis of MRE11′s role in Plasmodium development during the mosquito stages and offers a potential target for therapeutic intervention during malaria parasite transmission.

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Testing configurations of Attractive Toxic Sugar Bait (ATSB) stations in Mali, West Africa, for improving the control of malaria parasite transmission by vector mosquitoes and minimizing their effect on non-target insects

10.21203/rs.3.rs-46985/v2 ◽

2021 ◽

Author(s):

Rabiatou A. Diarra ◽

Mohamed M. Traore ◽

Amy M Junnila ◽

Sekou F. Traore ◽

Seydou Doumbia ◽

...

Keyword(s):

Malaria Parasite ◽

Uv Light ◽

Visual Orientation ◽

Mosquito Vector ◽

Parasite Transmission ◽

Feeding Rates ◽

Light Traps ◽

Sugar Feeding ◽

Bait Stations ◽

The Impact

Abstract Background Attractive Toxic Sugar Baits (ATSBs) successfully reduced Anopheles mosquito vector populations and malaria parasite transmission in Mali, but application methods need to be improved for wide-scale use, and effects on non-target organisms (NTOs) must be assessed. The goals of this study were to determine on a village level the effect of different outdoor configurations of ATSB bait stations to 1) achieve > 25% Anopheles mosquito vector daily feeding rate for both males and females and 2) minimize the effect on non-target organisms. Methods Dye was added to Attractive Sugar Bait Stations (ASB – without toxin) to mark mosquitoes feeding on the sugar baits, and CDC UV light traps were used to monitor mosquitoes for the presence of the dye. Yellow plates, pitfall traps, Malaise traps, UV light traps, UV tray traps, and sweep nets were used to trap and sample non-target organisms (NTOs) for dye, indicating feeding on the ASB. ASB stations were hung on outer walls of village homes to determine the impact of different densities of ASBs (1,2, or 3 per home) as well as the impact of ASB height (1 m or 1.8 m above the ground on sugar feeding by anophelines. These experiments were carried out separately, on consecutive nights for mosquito and NTO monitoring. Eight villages in the Koulikoro province were chosen as the experimental locations. Results The use of one ASB station per house marked 23.11% of female and 7.11% of male An. gambiae s.l. While two and three ASB stations per house gave feeding rates above the 25% goal, there was no statistical difference in the percentage of marked mosquitoes (p=0.3141 females; p=0.9336 males). There was no difference in sugar feeding on ASB stations when hung at 1.0 and 1.8 m and (p=0.5170 females; p=0.9934 males); however, ASBs at 1.8 m had less accidental damage from village residents and animals, and subsequent invasion of non-targets through rips or holes produced. ASB stations at 1.8 m above ground were fed on by three of seven monitored insect orders. Feeding rates were less than 0.015% of total trap catches and as low as 0.0001%. The monitored orders were: Hymenoptera [ants (Formicidae), bees (Apidae), and wasps (Vespidae)], Lepidoptera (Rhopalocera, Bombyces, Geometroidea, Noctuoidea, Sphingidae, Pyraloidea), Coleoptera (Carabidae, Tenebrionidae, Scarabaeidae, Cerambycidae, and Chrysomelidae), Diptera (Brachycera, Chironomidae), Hemiptera (Cicadomorpha and Heteroptera), Neuroptera (Myrmeleontiformia) and Orthoptera (Caelifera and Ensifera). Using one or two stations limited evidence of NTO feeding to ants (Hymenoptera), Brachycera, Heteroptera, Noctuiodea, Rhopalocera, wasps (Vespidae) and wild bees (Apidae) (both Hymenoptera) and had a significantly reduced percentage of stained individuals compared to three stations which had the highest feeding rates amongst NTOs. The percentages of stained individuals were as follows: 6.84 ± 2.03% Brachycera were stained followed by wasps (Hymenoptera: Vespidae) 5.32 ± 2.27%, and Rhopalocera 2.22 ± 1.79%. Hanging the optimal number of stations per house for catching mosquitoes (two) 1.8 m above ground, limited the groups of non-targets to Brachycera, Chironomidae, Noctuoidea, Rhopalocera, parasitic wasps and wasps (both Hymenoptera: Vespidae). The three most commonly stained non-target insect groups at this height were wasps (Vespidae) (1.65 ± 0.75%), Chironomidae (0.99 ± 0.37), and Brachycera (1.55 ± 0.69%). Feeding at this height only occurred when stations were damaged.Conclusions The goal of marking one quarter of the total Anopheles mosquito vector population per day was obtained using 2 bait stations at 1.8 m height above the ground on the outer walls of houses. This configuration of ATSB stations also had minimal effects on non-target insects: only 0.0001% to 0.013% of specimens (in three orders) were marked. Stations hung 1.8 m above the ground had less accidental damage from passing people and livestock. The minimal marking of non-target insects may be attributed to visual orientation of non-mosquito insects while mosquitoes, are mostly guided by olfactory cues. Furthermore, the bait stations have a membrane cover, which if intact, is impenetrable to most sugar feeding non-target insects but is pierced by the stylets of the mosquito proboscis. Thus, most non-target insects are not exposed to the toxin even if they approach the bait stations.

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A Plasmodium yoelii Mei2-Like RNA Binding Protein Is Essential for Completion of Liver Stage Schizogony

Infection and Immunity ◽

10.1128/iai.01417-15 ◽

2016 ◽

Vol 84 (5) ◽

pp. 1336-1345 ◽

Cited By ~ 8

Author(s):

Dorender A. Dankwa ◽

Marshall J. Davis ◽

Stefan H. I. Kappe ◽

Ashley M. Vaughan

Keyword(s):

Rna Binding ◽

Rna Binding Proteins ◽

Plasmodium Yoelii ◽

Parasite Development ◽

Mammalian Host ◽

Mosquito Vector ◽

Wild Type ◽

Liver Stage ◽

Content Type ◽

Stage Development

Plasmodiumparasites employ posttranscriptional regulatory mechanisms as their life cycle transitions between host cell invasion and replication within both the mosquito vector and mammalian host. RNA binding proteins (RBPs) provide one mechanism for modulation of RNA function. To explore the role ofPlasmodiumRBPs during parasite replication, we searched for RBPs that might play a role during liver stage development, the parasite stage that exhibits the most extensive growth and replication. We identified a parasite ortholog of theMei2(Meiosisinhibited 2) RBP that is conserved amongPlasmodiumspecies (PlasMei2) and exclusively transcribed in liver stage parasites. Epitope-taggedPlasmodium yoeliiPlasMei2 was expressed only during liver stage schizogony and showed an apparent granular cytoplasmic location. Knockout ofPlasMei2(plasmei2−) inP. yoeliionly affected late liver stage development. TheP. yoeliiplasmei2−liver stage size increased progressively until late in development, similar to wild-type parasite development. However,P. yoeliiplasmei2−liver stage schizonts exhibited an abnormal DNA segregation phenotype and failed to form exoerythrocytic merozoites. Consequently the cellular integrity ofP. yoeliiplasmei2−liver stages became increasingly compromised late in development and the majority ofP. yoeliiplasmei2−underwent cell death by the time wild-type liver stages mature and release merozoites. This resulted in a complete block ofP. yoeliiplasmei2−transition from liver stage to blood stage infection in mice. Our results show for the first time the importance of aPlasmodiumRBP in the coordinated progression of late liver stage schizogony and maturation of new invasive forms.

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Testing Configurations of Attractive Toxic Sugar Bait (ATSB) Stations in Mali, West Africa, for Improving the Control of Malaria Parasite Transmission by Vector Mosquitoes and Minimizing Their Effect on Non-target Insects

10.21203/rs.3.rs-46985/v1 ◽

2020 ◽

Author(s):

Rabiatou A. Diarra A. Diarra ◽

Mohamed M. Traore ◽

Amy M Junnila ◽

Sekou F. Traore ◽

Seydou Doumbia ◽

...

Keyword(s):

Malaria Parasite ◽

Uv Light ◽

Visual Orientation ◽

Mosquito Vector ◽

Parasite Transmission ◽

Feeding Rates ◽

Light Traps ◽

Sugar Feeding ◽

Bait Stations ◽

The Impact

Abstract Background Attractive Toxic Sugar Baits (ATSBs) successfully reduced Anopheles mosquito vector populations and malaria parasite transmission in Mali but application methods need to be improved for wide-scale use, and minimization of effects on non-target organisms (NTOs) must be assessed. The goals of this study were to determine on a village level the effect of different outdoor configurations of ATSB bait stations to 1) achieve > 25% Anopheles mosquito vector daily feeding rate for both males and females and 2) minimize the effect on non-target organisms. Methods Dye was added to Attractive Sugar Bait Stations (ASB – without toxin) to mark mosquitoes feeding on the sugar baits, and CDC UV light traps were used to monitor mosquitoes for the presence of the dye. Yellow plates, pitfall traps, Malaise traps, UV light traps, UV tray traps, and sweep nets were used to trap and sample non-target organisms (NTOs) for dye, indicating feeding on the ASB. ASB stations were hung on outer walls of village homes to determine the impact of different densities of ASBs (1,2, or 3 per home) as well as the impact of ASB height (1 m or 1.8 m above the ground on sugar feeding by anophelines. These experiments were carried out separately, on consecutive nights for mosquito and NTO monitoring. Eight villages in the Koulikoro province were chosen as the experimental locations Results The use of one ASB station per house marked 23.11% of female and 14.64% of male An. gambiae s.l. While two and three ASB stations per house gave feeding rates above the 25% goal, there was no statistical difference in the percentage of marked mosquitoes (p = 0.3141 females; p = 0.9336 males). There was no difference in sugar feeding on ASB stations when hung at 1.0 and 1.8 m and (p = 0.5170 females; p = 0.9934 males); however, ASBs at 1.8 m had less accidental damage from village residents and animals, and subsequent invasion of non-targets through rips or holes produced. ASB stations at 1.8 m above ground were fed on by three of seven monitored insect orders. Feeding rates were less than 0.015% of total trap catches and as low as 0.0001%. The monitored orders were: Hymenoptera [ants (Formicidae), bees (Apidae), and wasps (Vespidae)], Lepidoptera (Rhopalocera, Bombyces, Geometroidea, Noctuoidea, Sphingidae, Pyraloidea), Coleoptera (Carabidae, Tenebrionidae, Scarabaeidae, Cerambycidae, and Chrysomelidae), Diptera (Brachycera, Chironomidae), Hemiptera (Cicadomorpha and Heteroptera), Neuroptera (Myrmeleontiformia) and Orthoptera (Caelifera and Ensifera). Using one or two stations limited evidence of NTO feeding to ants (Hymenoptera), Brachycera, Heteroptera, Noctuiodea, Rhopalocera, wasps (Vespidae) and wild bees (Apidae) (both Hymenoptera) and had a significantly reduced percentage of stained individuals compared to three stations which produced the highest number of NTOs. The percentages of stained individuals were as follows: Brachycera accounted for 6.84 ± 2.03% of stained insects, wasps (Hymenoptera: Vespidae) for 5.32 ± 2.27%, and Rhopalocera for 2.22 ± 1.79%. Hanging the optimal number of stations per house for catching mosquitoes (two) 1.8 m above ground limited the groups of non-targets to Brachycera, Chironomidae, Noctuoidea, Rhopalocera, parasitic wasps and wasps (both Hymenoptera: Vespidae). The three most commonly stained non-target insect groups at this height were wasps (Vespidae) (1.65 ± 0.75%), Chironomidae (0.99 ± 0.37), and Brachycera (1.55 ± 0.69%). Feeding at this height only occurred when stations were damaged. Conclusions The goal of marking one quarter of the total Anopheles mosquito vector population per day was obtained using 2 bait stations at 1.8 m height above the ground on the outer walls of houses. This configuration of ATSB stations also had minimal effects on non-target insects: only 0.0001–0.013% of specimens (in three orders) were marked. Stations hung 1.8 m above the ground had less accidental damage from passing people and livestock. The minimal marking of non-target insects may be attributed to visual orientation of non-mosquito insects while mosquitoes, are mostly guided by olfactory cues. Furthermore, the bait stations have a membrane cover, which if intact, is impenetrable to most sugar feeding non-target insects but is pierced by the stylets of the mosquito proboscis. Thus, most non-target insects are not exposed to the toxin even if they approach the bait stations.

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Detection of the Rhoptry Neck Protein Complex in Plasmodium Sporozoites and Its Contribution to Sporozoite Invasion of Salivary Glands

mSphere ◽

10.1128/msphere.00325-20 ◽

2020 ◽

Vol 5 (4) ◽

Cited By ~ 1

Author(s):

Mamoru Nozaki ◽

Minami Baba ◽

Mayumi Tachibana ◽

Naohito Tokunaga ◽

Motomi Torii ◽

...

Keyword(s):

Salivary Glands ◽

Protein Complex ◽

Malaria Parasite ◽

Gene Knockdown ◽

Mammalian Host ◽

Target Cells ◽

Specific Gene ◽

Invasion Mechanisms ◽

Attachment Ability ◽

Rhoptry Neck Protein

ABSTRACT In the Plasmodium life cycle, two infectious stages of parasites, merozoites and sporozoites, share rhoptry and microneme apical structures. A crucial step during merozoite invasion of erythrocytes is the discharge to the host cell membrane of some rhoptry neck proteins as a complex, followed by the formation of a moving junction involving the parasite-secreted protein AMA1 on the parasite membrane. Components of the merozoite rhoptry neck protein complex are also expressed in sporozoites, namely, RON2, RON4, and RON5, suggesting that invasion mechanism elements might be conserved between these infective stages. Recently, we demonstrated that RON2 is required for sporozoite invasion of mosquito salivary gland cells and mammalian hepatocytes, using a sporozoite stage-specific gene knockdown strategy in the rodent malaria parasite model, Plasmodium berghei. Here, we use a coimmunoprecipitation assay and oocyst-derived sporozoite extracts to demonstrate that RON2, RON4, and RON5 also form a complex in sporozoites. The sporozoite stage-specific gene knockdown strategy revealed that both RON4 and RON5 have crucial roles during sporozoite invasion of salivary glands, including a significantly reduced attachment ability required for the onset of gliding. Further analyses indicated that RON2 and RON4 reciprocally affect trafficking to rhoptries in developing sporozoites, while RON5 is independently transported. These findings indicate that the interaction between RON2 and RON4 contributes to their stability and trafficking to rhoptries, in addition to involvement in sporozoite attachment. IMPORTANCE Sporozoites are the motile infectious stage that mediates malaria parasite transmission from mosquitoes to the mammalian host. This study addresses the question whether the rhoptry neck protein complex forms and functions in sporozoites, in addition to its role in merozoites. By applying coimmunoprecipitation and sporozoite stage-specific gene knockdown assays, it was demonstrated that RON2, RON4, and RON5 form a complex and are involved in sporozoite invasion of salivary glands via their attachment ability. These findings shed light on the conserved invasion mechanisms among apicomplexan infective stages. In addition, the sporozoite stage-specific gene knockdown system has revealed for the first time in Plasmodium that the RON2 and RON4 interaction reciprocally affects their stability and trafficking to rhoptries. Our study raises the possibility that the RON complex functions during sporozoite maturation as well as migration toward and invasion of target cells.

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Inhibitor of Cysteine Proteases Is Critical for Motility and Infectivity of Plasmodium Sporozoites

mBio ◽

10.1128/mbio.00874-13 ◽

2013 ◽

Vol 4 (6) ◽

Cited By ~ 12

Author(s):

Katja E. Boysen ◽

Kai Matuschewski

Keyword(s):

Life Cycle ◽

Salivary Glands ◽

Cysteine Proteases ◽

Gliding Motility ◽

Parasitic Infections ◽

Mammalian Host ◽

Insect Vector ◽

Mosquito Vector ◽

Infected Female ◽

Wide Range

ABSTRACT Malaria is transmitted when motile sporozoites are injected into the dermis by an infected female Anopheles mosquito. Inside the mosquito vector, sporozoites egress from midgut-associated oocysts and eventually penetrate the acinar cells of salivary glands. Parasite-encoded factors with exclusive vital roles in the insect vector can be studied by classical reverse genetics. Here, we characterized the in vivo roles of Plasmodium berghei falstatin/ICP (inhibitor of cysteine proteases). This protein was previously suggested to act as a protease inhibitor during erythrocyte invasion. We show by targeted gene disruption that loss of ICP function does not affect growth inside the mammalian host but causes a complete defect in sporozoite transmission. Sporogony occurred normally in icp(−) parasites, but hemocoel sporozoites showed a defect in continuous gliding motility and infectivity for salivary glands, which are prerequisites for sporozoite transmission to the mammalian host. Absence of ICP correlates with enhanced cleavage of circumsporozoite protein, in agreement with a role as a protease regulator. We conclude that ICP is essential for only the final stages of sporozoite maturation inside the mosquito vector. This study is the first genetic evidence that an ICP is necessary for the productive motility of a eukaryotic parasitic cell. IMPORTANCE Cysteine proteases and their inhibitors are considered ideal drug targets for the treatment of a wide range of diseases, including cancer and parasitic infections. In protozoan parasites, including Leishmania, Trypanosoma, and Plasmodium, cysteine proteases play important roles in life cycle progression. A mouse malaria model provides an unprecedented opportunity to study the roles of a parasite-encoded inhibitor of cysteine proteases (ICP) over the entire parasite life cycle. By precise gene deletion, we found no evidence that ICP influences disease progression or parasite virulence. Instead, we discovered that this factor is necessary for parasite movement and malaria transmission from mosquitoes to mammals. This finding in a fast-moving unicellular protozoan has important implications for malaria intervention strategies and the roles of ICPs in the regulation of eukaryotic cell migration.

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MRE11 is crucial for malaria transmission and its absence affects expression of interconnected networks of key genes essential for life

10.1101/2020.08.24.258657 ◽

2020 ◽

Author(s):

David S. Guttery ◽

Abhinay Ramaprasad ◽

David J. P. Ferguson ◽

Mohammad Zeeshan ◽

Rajan Pandey ◽

...

Keyword(s):

Dna Damage Response ◽

Plasmodium Berghei ◽

Genome Stability ◽

Malaria Parasite ◽

Mosquito Vector ◽

Parasite Transmission ◽

Biological Processes ◽

Cluster Assembly ◽

Damage Response ◽

Key Genes

AbstractThe Meiotic Recombination 11 protein (MRE11) plays a key role in DNA damage response and maintenance of genome stability. However, little is known about its function during development of the malaria parasite Plasmodium. Here, we present a functional, ultrastructural and transcriptomic analysis of Plasmodium MRE11 during its life-cycle in both mammalian and mosquito vector hosts. Genetic disruption of Plasmodium berghei mre11 (PbMRE11) results in significant retardation of oocyst development in the mosquito midgut associated with cytoplasmic and nuclear degeneration, along with concomitant ablation of sporogony and subsequent parasite transmission. Further, absence of PbMRE11 results in significant transcriptional downregulation of genes involved in key interconnected biological processes that are fundamental to all eukaryotic life including ribonucleoprotein biogenesis, spliceosome function and iron-sulphur cluster assembly. Overall, our study provides a comprehensive functional analysis of MRE11’s role in Plasmodium development during the mosquito stages and offers a potential target for therapeutic intervention during malaria parasite transmission.

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Transcriptomics and proteomics reveal two waves of translational repression during the maturation of malaria parasite sporozoites

Nature Communications ◽

10.1038/s41467-019-12936-6 ◽

2019 ◽

Vol 10 (1) ◽

Cited By ~ 18

Author(s):

Scott E. Lindner ◽

Kristian E. Swearingen ◽

Melanie J. Shears ◽

Michael P. Walker ◽

Erin N. Vrana ◽

...

Keyword(s):

Plasmodium Falciparum ◽

Salivary Gland ◽

Protein Expression ◽

Salivary Glands ◽

Malaria Parasite ◽

Plasmodium Yoelii ◽

Translational Repression ◽

Successful Development ◽

Regulate Protein ◽

Validation Experiments

Abstract Plasmodium sporozoites are transmitted from infected mosquitoes to mammals, and must navigate the host skin and vasculature to infect the liver. This journey requires distinct proteomes. Here, we report the dynamic transcriptomes and proteomes of both oocyst sporozoites and salivary gland sporozoites in both rodent-infectious Plasmodium yoelii parasites and human-infectious Plasmodium falciparum parasites. The data robustly define mRNAs and proteins that are upregulated in oocyst sporozoites (UOS) or upregulated in infectious sporozoites (UIS) within the salivary glands, including many that are essential for sporozoite functions in the vector and host. Moreover, we find that malaria parasites use two overlapping, extensive, and independent programs of translational repression across sporozoite maturation to temporally regulate protein expression. Together with gene-specific validation experiments, these data indicate that two waves of translational repression are implemented and relieved at different times during sporozoite maturation, migration and infection, thus promoting their successful development and vector-to-host transition.

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