Plasmodium berghei ookinetes induce nitric oxide production in Anopheles pseudopunctipennis midguts cultured in vitro

• Published in: Insect biochemistry and molecular biology Vol. 34; no. 9; pp. 893 - 901
• Main Authors: Herrera-Ortíz, Antonia, Lanz-Mendoza, Humberto, Martínez-Barnetche, Jesús, Hernández-Martínez, Salvador, Villarreal-Treviño, Cuauhtémoc, Aguilar-Marcelino, Liliana, Rodríguez, Mario H.
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01-09-2004
• Subjects: Amino Acid Sequence; amino acid sequences; Animals; Anopheles - microbiology; Anopheles - parasitology; Anopheles pseudopunctipennis; Culicidae; Digestive System - enzymology; Digestive System - microbiology; Female; Gene Expression Profiling; gene induction; Gram-Negative Bacteria - pathogenicity; Gram-Positive Bacteria - pathogenicity; insect vectors; L-dopa; Levodopa - physiology; microorganisms; midgut; Molecular Sequence Data; Nitric oxide; Nitric Oxide - biosynthesis; Nitric Oxide - physiology; Nitric oxide synthase; Nitric Oxide Synthase - metabolism; nucleotide sequences; Ookinetes; oxidation; Oxidative stress; Plasmodium; Plasmodium berghei; Plasmodium berghei - pathogenicity; Plasmodium berghei - physiology; Reactive Oxygen Species; Reverse Transcriptase Polymerase Chain Reaction; Zygote - physiology; Plasmodium; Oxidative stress; Nitric oxide synthase; Anopheles pseudopunctipennis; Ookinetes; Nitric oxide
• ISSN: 0965-1748; 1879-0240
• DOI: 10.1016/j.ibmb.2004.05.007

The
Anopheles pseudopunctipennis nitric oxide synthase gene (ApNOS) was identified and its partial sequence showed high homology with NOS from
A. stephensi,
A. gambiae (putative sequence), and
Drosophila melanogaster. ApNOS was mainly expressed in male and female adult mosquitoes and was induced by a blood meal. Nitric oxide (NO) was produced by in vitro-cultured mosquito midguts inoculated by enema with
Plasmodium berghei ookinetes,
Saccharomyces cerevisiae, Gram-positive bacteria (
Micrococcus luteus), but not with Gram-negative bacteria (
Klebsiella pneumoniae,
Escherichia coli or
Serratia marcescens). Dihydroxyphenylalanine (
l-DOPA) oxidation induced the generation of NO in midguts in vitro, and hydrogen peroxide generated during its oxidation induced ApNOS expression.
P. berghei ookinetes exposed in vitro to
l-DOPA and sodium nitroprusside (a NO generator) were killed. These observations demonstrate that reactive oxygen and nitrogen intermediates constitute a part of the cytotoxic arsenal employed by
Anopheles mosquitoes against microbial pathogens and
Plasmodium ookinetes.