Fig. 1. Juvenile hormone III (JH III) suppresses basal antimicrobial peptide (AMP) expression in whole flies. Shown are log₂-fold change values (JH/control) for 12 AMP transcripts from microarray analyses performed in duplicate. ^*P<0.05 (Student's t-test). Since the physiological role of JH is not well understood in males, we only used females in this array experiment. We suggest that microarrays might be a particularly useful tool when studying whole-organism effects of hormonal signaling: hormones can be topically applied or injected, are taken up into the circulation, act on responsive target tissues, and elicit a systemic, whole-organism response (e.g. immune modulation).