Differential protein expression in maize (<i>Zea mays</i>) in response to insect attack

Abstract

Maize (Zea mays) is a major food stable in sub-Saharan Africa. However, yields are constrained by insect pests. Insect feeding induces a number of changes in genes encoding different proteins and the plant’s response can either be direct or indirect, or both. In this study, maize plants were infested with two insects with different feeding strategies (Spodoptera littoralis, chewing insect and Busseola fusca, stem borer) to investigate differential protein expression using the Proteomics technique. Infestation of S. littoralis (3rd instar larvae) resulted in 14 spots being up-regulated and 7 being down-regulated. Similarly, infestation of maize with B. fusca (3rd instar larvae) resulted in 12 spots being up-regulated and 9 spots being down-regulated. Interestingly, of those up-regulated only 9 were common to both insects, with only 4 common to both in terms of down regulation. Infestation of maize with S. littoralis resulted in a greater number of spots being up-regulated and less being down-regulated compared to maize infested with B. fusca. Unfortunately, we were unable to identify the proteins represented by these spots.

Key words: Busseola fusca, down-regulation, expression, proteomics, Spodoptera littoralis, up-regulation.