Biochemical Characters And Physiological Functions Of Venoms From Two Peromalid Wasps, Pteromalus Puparum And Nasonia Vitripennis (Hymenoptera: Pteromalidae)

Studies of biochemial characters and physiological founctions of parasitoid were foused on braconid and ichneumonid wasps, but in other families were fewer. So we studied the biochemical characters and physiological functions of venoms from two peromalid wasps, Pteromalus puparum and Nasonia vitripennis. The results were shown as follows.1. Host immune inhibiting factors in the reproductive system of Pteromalus puparumExtracts of ovary, eggs, oviduct from female P. puparum and testes, male accessory gland from male P. puparum had no effects on spreading, mortality and encapsulation capability of hemocytes from P. rapae and P. xuthus pupae. But venom from female P. puparum could inhibit the spreading and encapsulation capability of the hemocytes and elicit significant death of hemocytes. We considered venom is the host immunity inhibiting factor in P. puparum female. Venom functions in the parasitoid was different with venoms from braconid and ichneumonid wasps had polydnavirus.2. Development of venom apparatus from two pteromalid wasps and their relationship with the oogenesisThe length of venom glands from female P. puparum and N. vitripennis fed with 20% honey water had no significantly change with the development of female wasps, but the diameters of venom reservoir and proteins in them increased rapidly in the first 3 days after female wasps' eclosion, and persisted at the levels until the death of female wasps. The length of venom glands from non-fed P. puparum and N. vitripennis female also had no significantly changes, but the development of venom reservoirs were much slower. Mating and feeding had no effects on the length of venom glands from P. puparum and N. vitripennis female, mating had no effects on thediameters and protein content of venom reservoirs, but feeding had significantly beneficial effects on them.Development of venom apparatus from mating and feeding P. puparum had positive relationship with the numbers of mature eggs and negative relationship with the numbers of grade I and grade II eggs from the ovary. But development of venom apparatus from mating and feeding N. vitrirpennis had no correlation with the numbers of mature eggs and immature eggs except that venom reservoir diameter had negative relationship with the numbers of grade II eggs in the ovary. Parts of venom apparatus of two pteromalid wasps also had positive relationships with each other.3. Composition and molecular character of venom proteins from two pteromalid waspsAnalysis of the 5 ~ 15% gradent-PAGE profile revealed the presence of 12 protein bands with molecular weight ranging from 17.47 to 879.67 kDa in the P. puparum venom, of which 558.64 kDa, 308 kDa and 178.17 kDa proteins were the highest three in the venom. The factors in P. puparum venom inhibiting the spreading and inducing the death of hosts' hemocytes were both proteins with native molecular weight above 100 kDa. Conversely, 9 protein bands with molecular weight between 17.62 to 809.94 kDa were detected in the N. vitripennis venom.Analysis of the 10% SDS-PAGE profile revealed the presence of 17 protein bands with molecular weight ranging from 14.11 kDa to 165.18 kDa, of which 9 protein bands between 21.17 ~ 44.41 kDa were relatively abundant, were observed in P. puparum venom. In contrast, 14 protein bands between 14.11 ~ 155.93 kDa, of which 6 protein bands between 21.15 ~ 36.68 kDa were relatively rich, were found in N. vitripennis venom. The factors in P. puparum venom inhibiting the spreading and inducing the death of hosts' hemocytes were both proteins with native molecular weight above 100 kDa.pi of venom proteins from P. puparum were between 4 and 7, and 5 to 10 from N. vitripennis. After analyzed with MALDI-TOF MS for seven higher expression spots from 2-DE gel of P. puparum venom and searched in UCSF with MS-FIT, we found the matching ratio of the checking proteins and proteins from database were very lower, with the highest matching ratio of 35%.4. Physical and chemical factors affected the physiological functions of venomsfrom Pteromalus puparum and N...