BhSGAMP-1, a Gene That Encodes an Antimicrobial Peptide, Is Developmentally Regulated by the Direct Action of 20-OH Ecdysone in the Salivary Gland of Bradysia hygida (Diptera, Sciaridae)

Author(s)

Zanarotti, Gabriela Morilha ^[1] ; Candido-Silva, Juliana A. ^[1] ; de Almeida, Jorge Cury ^[1]

Affiliation

^[1] Univ Sao Paulo, Dept Biol Celular & Mol & Bioagentes Patogen, Fac Med Ribeirao Preto, BR-14049900 Ribeirao Preto, SP - Brazil

• Document type: Journal article
• Source: GENESIS; v. 47, n. 12, p. 847-857, DEC 2009.
• Web of Science Citations: 3

Abstract

Recently we have shown that BhSGAMP-1 is a developmentally regulated reiterated gene that encodes an antimicrobial peptide (AMP) and is expressed exclusively in the salivary glands, at the end of the larval stage. We show, for the first time, that a gene for an AMP is directly activated by 20-OH ecdysone. This control probably involves the participation of short-lived repressor(s). We also found that the promoter of BhSGAMP-1 is not equipped with elements that respond to infection, provoked by the injection of microorganisms, in the salivary glands or in the fat body. We produced polyclonal antibodies against the synthetic peptide and found that the BhSGAMP-1 peptide is secreted in the saliva. The BhSGAMP-1 gene was also activated during the third larval molt. These facts confirm our hypothesis that this preventive system of defense was selected to produce an environment free of harmful microorganisms in the insect's immediate vicinity, during molts. genesis 47:847-857, 2009. (C) 2009 Wiley-Liss, Inc. (AU)