Format

Send to

Choose Destination
Parasit Vectors. 2015 Aug 19;8:424. doi: 10.1186/s13071-015-1016-x.

Anopheles stephensi p38 MAPK signaling regulates innate immunity and bioenergetics during Plasmodium falciparum infection.

Author information

1
Department of Medical Microbiology and Immunology, School of Medicine, University of California Davis, 3437 Tupper Hall, One Shields Avenue, Davis, CA, 95616, USA. bwangucd@gmail.com.
2
Department of Medical Microbiology and Immunology, School of Medicine, University of California Davis, 3437 Tupper Hall, One Shields Avenue, Davis, CA, 95616, USA. npakpour@ucdavis.edu.
3
Department of Molecular Biosciences, School of Veterinary Medicine, University of California Davis, Davis, CA, USA. enapoli@ucdavis.edu.
4
Department of Medical Microbiology and Immunology, School of Medicine, University of California Davis, 3437 Tupper Hall, One Shields Avenue, Davis, CA, 95616, USA. drexlera@who.int.
5
Department of Medical Microbiology and Immunology, School of Medicine, University of California Davis, 3437 Tupper Hall, One Shields Avenue, Davis, CA, 95616, USA. ekglennon@ucdavis.edu.
6
Department of Medical Microbiology and Immunology, School of Medicine, University of California Davis, 3437 Tupper Hall, One Shields Avenue, Davis, CA, 95616, USA. fvetwsp@ku.ac.th.
7
Department of Medical Microbiology and Immunology, School of Medicine, University of California Davis, 3437 Tupper Hall, One Shields Avenue, Davis, CA, 95616, USA. kcheung@ucdavis.edu.
8
Department of Medical Microbiology and Immunology, School of Medicine, University of California Davis, 3437 Tupper Hall, One Shields Avenue, Davis, CA, 95616, USA. apaguirre@ucdavis.edu.
9
Department of Medical Microbiology and Immunology, School of Medicine, University of California Davis, 3437 Tupper Hall, One Shields Avenue, Davis, CA, 95616, USA. jmklyver@ucdavis.edu.
10
Department of Entomology and Nematology, University of California Davis, Davis, CA, USA. eelewis@ucdavis.edu.
11
Genome and Biomedical Sciences Center, University of California Davis, Davis, CA, USA. raeigen@yahoo.com.
12
Genome and Biomedical Sciences Center, University of California Davis, Davis, CA, USA. bsphinney@ucdavis.edu.
13
Department of Molecular Biosciences, School of Veterinary Medicine, University of California Davis, Davis, CA, USA. cgiulivi@ucdavis.edu.
14
Medical Investigations of Neurodevelopmental Disorders (MIND) Institute, University of California Davis, Davis, CA, USA. cgiulivi@ucdavis.edu.
15
Department of Medical Microbiology and Immunology, School of Medicine, University of California Davis, 3437 Tupper Hall, One Shields Avenue, Davis, CA, 95616, USA. sluckhart@ucdavis.edu.

Abstract

BACKGROUND:

Fruit flies and mammals protect themselves against infection by mounting immune and metabolic responses that must be balanced against the metabolic needs of the pathogens. In this context, p38 mitogen-activated protein kinase (MAPK)-dependent signaling is critical to regulating both innate immunity and metabolism during infection. Accordingly, we asked to what extent the Asian malaria mosquito Anopheles stephensi utilizes p38 MAPK signaling during infection with the human malaria parasite Plasmodium falciparum.

METHODS:

A. stephensi p38 MAPK (AsP38 MAPK) was identified and patterns of signaling in vitro and in vivo (midgut) were analyzed using phospho-specific antibodies and small molecule inhibitors. Functional effects of AsP38 MAPK inhibition were assessed using P. falciparum infection, quantitative real-time PCR, assays for reactive oxygen species and survivorship under oxidative stress, proteomics, and biochemical analyses.

RESULTS:

The genome of A. stephensi encodes a single p38 MAPK that is activated in the midgut in response to parasite infection. Inhibition of AsP38 MAPK signaling significantly reduced P. falciparum sporogonic development. This phenotype was associated with AsP38 MAPK regulation of mitochondrial physiology and stress responses in the midgut epithelium, a tissue critical for parasite development. Specifically, inhibition of AsP38 MAPK resulted in reduction in mosquito protein synthesis machinery, a shift in glucose metabolism, reduced mitochondrial metabolism, enhanced production of mitochondrial reactive oxygen species, induction of an array of anti-parasite effector genes, and decreased resistance to oxidative stress-mediated damage. Hence, P. falciparum-induced activation of AsP38 MAPK in the midgut facilitates parasite infection through a combination of reduced anti-parasite immune defenses and enhanced host protein synthesis and bioenergetics to minimize the impact of infection on the host and to maximize parasite survival, and ultimately, transmission.

CONCLUSIONS:

These observations suggest that, as in mammals, innate immunity and mitochondrial responses are integrated in mosquitoes and that AsP38 MAPK-dependent signaling facilitates mosquito survival during parasite infection, a fact that may attest to the relatively longer evolutionary relationship of these parasites with their invertebrate compared to their vertebrate hosts. On a practical level, improved understanding of the balances and trade-offs between resistance and metabolism could be leveraged to generate fit, resistant mosquitoes for malaria control.

PMID:
26283222
PMCID:
PMC4539710
DOI:
10.1186/s13071-015-1016-x
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for BioMed Central Icon for PubMed Central
Loading ...
Support Center