The salivary protein Saglin facilitates efficient midgut colonization of Anopheles mosquitoes by malaria parasites.

Abstract

Malaria is caused by the unicellular parasite Plasmodium which is transmitted to humans through the bite of infected female Anopheles mosquitoes. To initiate sexual reproduction and to infect the midgut of the mosquito, Plasmodium gametocytes are able to recognize the intestinal environment after being ingested during blood feeding. A shift in temperature, pH change and the presence of the insect-specific compound xanthurenic acid have been shown to be important stimuli perceived by gametocytes to become activated and proceed to sexual reproduction. Here we report that the salivary protein Saglin, previously proposed to be a receptor for the recognition of salivary glands by sporozoites, facilitates Plasmodium colonization of the mosquito midgut, but does not contribute to salivary gland invasion. In mosquito mutants lacking Saglin, Plasmodium infection of Anopheles females is reduced, resulting in impaired transmission of sporozoites at low infection densities. Interestingly, Saglin can be detected in high amounts in the midgut of mosquitoes after blood ingestion, possibly indicating a previously unknown host-pathogen interaction between Saglin and midgut stages of Plasmodium. Furthermore, we were able to show that saglin deletion has no fitness cost in laboratory conditions, suggesting this gene would be an interesting target for gene drive approaches.

• Authors: Dennis Klug, Amandine Gautier, Eric Calvo, Eric Marois, Stéphanie A Blandin
• Journal: PLoS pathogens (PLoS Pathog) Vol. 19 Issue 3 Pg. e1010538 (03 2023) ISSN: 1553-7374 [Electronic] United States
• PMID: 36862755 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright: This is an open access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.

Chemical References

• Salivary Proteins and Peptides

Topics

• Animals
• Humans
• Female
• Anopheles (parasitology)
• Parasites
• Mosquito Vectors
• Plasmodium
• Malaria (parasitology)
• Sporozoites
• Salivary Proteins and Peptides