Project description:Background: Anopheles culicifacies is a rural vector of malaria in tropical and sub tropical South East Asian region. The salivary gland of the mosquito is the target for sporozoite interaction, blood feeding behavior, haemostasis and vector-parasite interactions. Malaria parasite matures inside the salivary gland, gain competence and transmitted to the host along with the saliva during biting. The importance of the proteins expressed in salivary gland is the first step in understanding the physiology of blood feeding and may provide insights into vector- parasite interactions. Since, no genomic or transcriptomics information is available of Anopheles culicifacies, therefore locally expressed functional proteins in salivary glands are of much importance. . Method: In this study, 1DE protein and in solution digestion was combined with tandem mass spectrometry (nano LC-MS/MS) and computational bioinformatics for data mining was employed to study the proteome profile of salivary glands of sugar fed An. culicifacies mosquito species. Functional annotation of all the identified proteins was carried out using gene ontology tools, CELLO and SMART analysis software. Results: Total 102 proteins were identified and analysed by SEQUEST algorithm against mosquito protein database from Uniprot/NCBI. Out of which 81 proteins were identified using gel free approach and 21 proteins using in-gel approach and 15 were common among these two approaches. All the identified proteins were categorized in to 23 groups of biological processes using GO tool. 7 proteins were depicted to be secretary in nature by investigating the signal peptide present. Potential proteins with unknown function were predicted by analyzing their functional association with other characterized proteins by STRING algorithm and were categorized in cell adhesion, cytoskeleton and membrane trafficking networks. Conclusion: Our study elucidates the first proteomic dataset of An. culicifacies salivary gland proteins. Functional annotation of salivary proteins and complementary gene ontology assignments in An. culicifacies species may contribute towards understanding the complex physiology of the tissues in this species. This proteome baseline data may facilitate the discernment of salivary glands and parasite correlation during blood feeding. Furthermore, this mass spectrometry based proteomic data may also provide insights into the elucidation of role of differential functional proteins present in refractory An. culicifacies mosquito and may be useful for development of effective malaria control strategies.
Project description:Background: Mosquito midgut is an important target for the host parasite interaction studies as it plays a major role in parasite growth and maturation and vector susceptibility. Proteomic approaches coupled with bioinformatics analysis have been used to study expression of functional proteins/enzymes of An. culicifacies susceptible and refractory species midgut in order to understand the mechanism of refractoriness that may help in contributing to unravel the host pathogen interactions. Methodology/Principle findings: In the present study proteomics approaches namely in solution and in gel digestion strategies followed by LC/MS/MS analysis were used. Further bioinformatics analysis were carried out to find out the functional annotated proteins, biological process, molecular function and their sub-cellular location using Gene ontology, SMART analysis, CELLO etc. In solution and in gel approach coupled with LC-MS/MS identified a total of 91 proteins in susceptible species and 69 proteins in refractory species. Comparative analysis between susceptible and refractory species of An. culicifacies indicated that mainly proteins involved in proteolysis mechanism, catalytic activity, peptidases activity and immune related proteins were found to be dominating in refractory as compared to susceptible species. Conclusion/Significance: Based on the present data a significant increase in number of proteins in midgut of refractory An. culicifacies species B were found that may conclude that these proteins may be responsible for the inhibiting parasite growth and linked to the melanization of oocysts or parasite lysis mechanisms in natural populations of refractory mosquito. Hence the progress of our studies at protein level suggests that these identified annotated putative proteins/enzymes may help to explore natural vector-parasite systems and reveal valuable insights into the mechanism of refractoriness which in turn further useful for bringing of novel strategies for control of malaria.