title: The STAT pathway mediates late-phase immunity against Plasmodium in the mosquito Anopheles gambiae.
abstract: The STAT family of transcription factors activates expression of immune system genes in vertebrates. The ancestral STAT gene (AgSTAT-A) appears to have duplicated in the mosquito Anopheles gambiae, giving rise to a second intronless STAT gene (AgSTAT-B), which we show regulates AgSTAT-A expression in adult females. AgSTAT-A participates in the transcriptional activation of nitric oxide synthase (NOS) in response to bacterial and plasmodial infection. Activation of this pathway, however, is not essential for mosquitoes to survive a bacterial challenge. AgSTAT-A silencing reduces the number of early Plasmodium oocysts in the midgut, but nevertheless enhances the overall infection by increasing oocyst survival. Silencing of SOCS, a STAT suppressor, has the opposite effect, reducing Plasmodium infection by increasing NOS expression. Chemical inhibition of mosquito NOS activity after oocyte formation increases oocyte survival. Thus, the AgSTAT-A pathway mediates a late-phase antiplasmodial response that reduces oocyst survival in A. gambiae.
authors.affiliation: Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20892-8130, USA.
authors.forename: Lalita
authors.initials: L
authors.lastname: Gupta
authors.forename: Alvaro
authors.initials: A
authors.lastname: Molina-Cruz
authors.forename: Sanjeev
authors.initials: S
authors.lastname: Kumar
authors.forename: Janneth
authors.initials: J
authors.lastname: Rodrigues
authors.forename: Rajnikant
authors.initials: R
authors.lastname: Dixit
authors.forename: Rodolfo E
authors.initials: RE
authors.lastname: Zamora
authors.forename: Carolina
authors.initials: C
authors.lastname: Barillas-Mury
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000852:Anopheles / Q000145:classification / Q000235:genetics / Q000276:immunology* / Q000469:parasitology*; D001483:Base Sequence; D002460:Cell Line; D005260:Female; D006790:Host-Parasite Interactions; D019476:Insect Proteins / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D008288:Malaria / Q000276:immunology / Q000469:parasitology; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D019001:Nitric Oxide Synthase / Q000235:genetics / Q000378:metabolism; D033661:Oocysts / Q000254:growth & development / Q000502:physiology; D010802:Phylogeny; D010961:Plasmodium / Q000254:growth & development* / Q000502:physiology; D050791:STAT Transcription Factors / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D016415:Sequence Alignment; D015398:Signal Transduction
chemical_list: D019476:Insect Proteins; D050791:STAT Transcription Factors; D019001:Nitric Oxide Synthase