Antimicrobial peptides: a key component of honey bee innate immunity

Honey bee immune responses are composed of a complex suite of individual immune mechanisms and special types of behavioral adaptations. The main focus of this paper is innate immunity in the honey bee, and specifically, the role and function of antimicrobial peptides (AMPs). Insect innate immunity constitutes evolutionary conserved defense strategies that provide immediate responses against invading pathogens. It consists of the three levels of resistance: physical barriers as the first line of defense, cell-mediated immunity, and cell-free humoral immunity, a complex network of intracellular signaling pathways leading to activation of a variety of humoral factors. Among those, AMPs are recognized as key components of humoral immunity in many types of organisms. The two basic mechanisms of action are: (1) the generation of leaks into prokaryotic membranes; and (2) either inhibition of bacterial protein translation or folding. Recently, four families of AMPs (i.e., apidaecins, abaecin, hymenoptaecin and de...