Jorge C de Almeida

Publications (2)5.05 Total impact

• Article: Developmental regulation of BhSGAMP-1, a gene encoding an antimicrobial peptide in the salivary glands of Bradysia hygida (Diptera, Sciaridae).

  Juliana A Candido-Silva, Gabriela M Zanarotti, Ana P Gallina, Jorge C de Almeida
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  ABSTRACT: It has recently become clear that the innate immune systems of insects and mammals are highly conserved; in general, these systems are stimulated upon infection by microorganisms. We found in the fly Bradysia hygida, a reiterated gene, which codes for a secretory peptide similar to plant-seed antimicrobial peptides. This gene BhSGAMP-1 is activated and expressed exclusively in the salivary glands of the larvae, while they are preparing to molt. In functional tests, synthetic BhSGAMP-1 peptide had broad spectrum antibiotic activity. Secretion of BhSGAMP-1 in the saliva could help prevent microbial infection during molting, by killing harmful microorganisms in the immediate vicinity of the animal. This is the first description of developmentally regulated defense peptide secretion in animals.
  genesis 11/2007; 45(10):630-8. · 2.53 Impact Factor
• Article: Programmed cell death in Bradysia hygida (Diptera, Sciaridae) salivary glands presents apoptotic features.

  Cláudio R Simon, Jorge C de Almeida
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  ABSTRACT: In this work, we present biochemical and morphological evidence that the final steps of programmed cell death (PCD) in the salivary glands of the inferior Diptera, Bradysia hygida, present apoptotic characteristics. In B. hygida, elimination of salivary glands is preceded by the establishment of a typical pattern of protein synthesis; increase in caspase activity; decrease in cell volume; nuclear pyknosis; nuclear DNA breakage; changes in the actin cytoskeleton; and most importantly, destruction of giant cells via formation of apoptotic bodies containing broken DNA or cytoplasm remains. Thus, elimination of B. hygida salivary glands by this process suggests that such mode of PCD is also involved in the destruction of entire organs in insects and, therefore, adds more complexity to the regulation of tissue elimination during development.
  genesis 10/2004; 40(1):22-31. · 2.53 Impact Factor