Molecular Characterization of Secreted Proteins from Salivary Gland Immunogenic Protein of Anopheles vagus

Abstract

Salivary mosquito's proteins have been widely acknowledged to contain factors important for pathogen transmission as well as for biomarker of Anopheles exposure. The objective of this study was to identify and characterize the secreted proteins from salivary glands and immunogenic proteins from of Anopheles (An.) vagus. A proteomic approach combining one-dimensional electrophoresis (1DE) was operationalized, followed by western blot analysis using human sera from healthy people living in an endemic area (Kendal, East Java - Indonesia); liquid chromatography mass spectrometry (LC-MS/MS) and bioinformatics analysis were conducted to gain direct insight into An. vagus salivary proteins. Three immunogenic proteins with molecular weight of 69, 75 and 232 kDa were identified. Apart from the housekeeping proteins identified by LC-MS/MS, there were also some proteins which played crucial role in the blood feeding process i.e AGA 5' nucleotidase family, for 69 & 75 kDa and SGS 4 for 232 kDa respectively. The other known proteins like vitellogenin, putative myosin class I heavy chain and heat shock protein 70 (Hsp70) were also identified. The majority of proteins were clearly characterized in Anopheles for their role in blood feeding, metabolism, cytoskeleton protein. and stress response.