Evolution of the Digestive Systems of Insects

• Grant number: 94/03354-5
• Support Opportunities: Research Projects - Thematic Grants
• Start date: July 01, 1995
• End date: December 31, 1998
• Field of knowledge: Biological Sciences - Biochemistry - Enzymology
• Principal Investigator: Walter Ribeiro Terra
• Grantee: Walter Ribeiro Terra
• Host Institution: Instituto de Química (IQ). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant(s): 96/04058-6 - The spatial organization of digestion in insects., AR.EXT; 96/04059-2 - Mechanisms of trypsin secretion., AR.EXT

Abstract

Transgenic plants express proteins which affect insect digestive functions,making them resistant to insects. The development of this field need a better understanding of insect digestion. Our research addresses to this subject from a broad point of view which includes the following aims: (a) Description of the organization of the digestive process in significant insect taxa to test the current hypothesis on the evolution of insect digestive systems. (b) Isolation of digestive enzymes and definition of their properties and functions with emphasis on cathepsin-like proteinases, which do not occur in vertebrates, and amylases, alfa-glucosidases and trehalases which have peculiar properties. (c) Study of the secretory mechanisms of digestive enzyme using mainly the technique of immunocytolocalization with antiserum produced against purified enzymes. (d) Correlations of midgut morphology and digestive physiology of adult insects from the major orders. (AU)