Study of vitellogenin in Boophilus annulatus tick larvae and its immunological aspects

Boophilus annulatus is an important one-host tick in the Mediterranean regions and Iran. It can transmit the Babesia bigemina, Babesia bovis and Anaplasma marginale to cattle. Nowadays, immunization programs by tick proteins is one of the potential methods for the control and prevention of tick infestations. Therefore, the characterization and identification of various tick proteins are necessary. Vitellogenin is a precursor of vitellin that is produced in mid gut cells and fat bodies in ticks. In this study, we characterized vitellogenin protein of B. annulatus unfed larvae using one- and two-dimensional electrophoresis and immunoblotting. In one-dimensional immunoblotting, 48, 70, 100, 130 and >250 kDa protein bands positively reacted with immune sera. In two-dimensional immunoblotting many protein spots positively reacted with immune sera. Six of them were analyzed by MALDI-TOF and MALDI-TOF- TOF mass spectrometry. The results showed that amino acid sequences of four immunogenic proteins with molecular weights of 38, 43, 85 and 97 kDa had identity to tick vitellogenin and its homologues (GP80), based on the Mascot search results. It seems that more knowledge on tick proteins including vitellogenin and their characterization could be useful for the development of anti-tick vaccines.