Phospholipase A2 (PLA2) hydrolyzes fatty acids from phospholipids at sn-2 position. Two immune-associated PLA2s are known in Spodoptera exigua. Both are calcium-independent cellular PLA2 (iPLA2A and iPLA2B). These iPLA2s are inducible to immune challenge using different epitopes such as virus, Gram+, Gram- bacteria, and fungi. However, their expression profiles are different between these two iPLA2s. Especially, immune challenge with Gram+ bacteria and fungi significantly up-regulated these iPLA2 expression, suggesting their expression under Toll signal pathway. RNA interferences of Toll or IMD signal components are being investigated.

The event that occur in sperm during chemotaxis are only partly known. As a essential step of fertilization, sperm cells should undergo capacitation process inside female genital tracts. To understand the molecular event of calcium signals on sperm cells, Fluo 4 loaded spermatozoa was treated with follicular fluid. The motility of sperm was reduced by follicular fluids. Simultaneously, level of calcium in head and tail was also reduced for 5 10 second. The inhibition of sperm motility was believed as a reversible event, so the follicular fluid in graffiaan follicles in vivo could act as a selector on active spermatozoa that recover motility and calcium signals during ovulation. This suggested that the normal levels of calcium in sperm was also critical for active state of sperm cells and the follicular fluids during ovulation could inhibit the motility of sperm cell via calcium signaling.