Identification And Expression Profiling Of Odorant Binding Proteins And Chemo-sensory Proteins Of Grape Phylloxera Daktulosphaira Vitifoliae Fitch

Grape phylloxera,Daktulosphaira vitifoliae(Fitch)(Homoptera: Phylloxeridae)is a worldwide pest damaging grape and an important quarantine pest in China.Its nymphs and adults suck juices from the roots and leaves of host plant,and induce radicicoles or gallicoles.It has caused great economic loss in the grapes all around the world.In insects,olfactory is essential for detecting hosts,selecting habitat and avoiding unsuitable environment.Olfactory proteins,such as odorant binding proteins(OBPs)and chemosensory proteins(CSPs),are the molecular basis of olfaction in insects.Identification of OBPs and CSPs of grape phylloxera would provide guidance to learn more about the relations between grape phylloxera and host,and may help in developing new methods to control this pest.In this study,OBPs and CSPs were identified from the Grape phylloxera transcriptomes.Sequence analysis was performed using different softwares.Tissue distribution of these proteins was determined by RT-PCR.Following are our results:1.The sequence of open reading frames(ORF)were identified from the transcriptomes of grape phylloxera and amplified by RT-PCR using grape phylloxera cDNA as template.The PCR products were purified,cloned to pMD-19 t cloning vector and sequenced.The results showed that the ORFs of 7 OBPs and 7 CSPs of grape phylloxera were obtained successfully.2.Sequence alignment of DviOBPs with OBPs from other aphid species indicated that DviOBP1?DviOBP2?DviOBP3?DviOBP4 and DviOBP7 have six conserved cysteine residues and belong to classical OBPs.DviOBP5 and DviOBP6 have a extra conserved cysteine residue in the downstream of the 6th conserved cysteine residue and belong to Plus-C OBPs.Sequence alignment of DviCSPs showed that these proteins have four conserved cysteine residues.These cysteine residues play a role in forming disulfide bond,and stabilize the protein structures to form a hydrophobic cavity.3.The expressing profiling of DviOBPs and DviCSPs in the head and body of grape phylloxera were determined by RT-PCR.The results showed that DviOBP1 and DviOBP6 were highly expressed in the head.DviOBP2?DviOBP3?DviOBP4?Dvi OBP5 and DviOBP7 were found in the head and body.All DviCSPs were expressed in head and body.