Salivary proteins and glycoproteins in phlebotomine sandflies of various species, sex and age

Abstract

Salivary gland proteins were studied in sandflies (Diptera: Psychodidae: Phlebotominae) by electrophoretic techniques. In Phlebotomus duboscqi Neveu-Lemaire the protein concentration was about 30 times higher in females than in males. SDS PAGE revealed eight major bands of 29-62 kDa in salivary gland extracts (SGE) from females, whereas only one band of 57kDa was detected in males. The number of protein components in SGE gradually increased with the age of females. In P. papatasi (Scopoli) the typical electrophoretic pattern was reached in 3-5 days after imago emergence, depending on the temperature at which females were maintained. All major protein components of the female SGE were present in the content of glands. Female SGE were compared in seven colonies of five Phlebotomus and Lutzomyia species; electrophoretic profiles distinguished between species and even between colonies of different geographical origin. In general, the highest variability of major protein components was observed in the 38-48kDa region. Four colonies of the subgenus Phlebotomus (P. duboscqi and P. papatasi) possessed common mobility polypeptides, the highest similarity was found between two colonies of P. papatasi. Other species tested significantly differed, specific prominent bands of 33, 35 and 38kDa were found in P. halepensis Theodor, P. perniciosus Newstead and Lutzomyia longipalpis (Lutz & Neiva), respectively. Glycoproteins in SGE of Lu. longipalpis and P. duboscqi females were identified and analysed using blotting with five lectin conjugates. Specific reaction of lectins ConA and WGA revealed the complex type of N-glycans in the 48 and 53-54kDa glycoproteins present in both species. Similar glycosylation was detected in species-specific bands of the 57-60 and 65-67 kDa in P. duboscqi and Lu. longipalpis, respectively. The high mannose type of glycosylation was found in the 20 and 39 kDa polypeptides of Lu. longipalpis and the 40-42 kDa polypeptides of P. duboscqi. Innate lectin activity specific for aminosugars was detected in SGE of P. duboscqi females using haemagglutination tests with rabbit erythrocytes.

Anticoagulant activity in salivary gland homogenates of Thyrsopelma guianense (Diptera: Simuliidae), the primary vector of onchocerciasis in the Brazilian Amazon

“…In sand flies, which are pool feeders like black flies, the number of protein components gradually increases with age and depends not only on sex but also on the physiological state in the female (Volf et al 2000). In contrast, our results showed that the protein concentration of the black fly salivary glands did not vary qualitatively during the first three days of female adult life.…”

Las glándulas salivales de dos flebotominos vectores de Leishmania: Lutzomyia migonei (França) y Lutzomyia ovallesi (Ortiz) (Diptera: Psychodidae)

“…Despite the similarity in expression in both species, qualitative and quantitative interspecific variation was present, such as appearance and disappearance of polypeptides, intensity and thickness of protein bands, and the detection of additional polypeptides with molecular weights >100 kDa ( migonei. The differences were in accordance with the published accounts of protein contents of a variety of sand fly species (7,21,38,39). Bloodmeal analysis indicated that these species were opportunistic feeders, with little attraction to a particular host species (32).…”

“…However, substantial variation has been reported in the immunosuppresive and anti-haemostatic components in saliva for different populations and species of sand flies (4,6,21). Antibodies against sand fly saliva in hamsters (10,22), in mice (11,14) and in humans have been demonstrated after exposure to feeding sand flies or salivary gland extracts (13,14,23).…”

Functional Characterization of HFR1, a High-MannoseN-Glycan-Specific Wheat Lectin Induced by Hessian Fly Larvae

“…For example, high-Man glycoproteins are integral to the midgut peritrophic matrix of mosquitoes (Anopheles gambiae and Aedes aegypti; Moskalyk et al, 1996). In addition, high-Man glycoproteins are components of salivary gland extracts from sandflies (Phlebotomus and Lutzomyia species; Volf et al, 2000). If high-Man glycoproteins are also present in Hessian fly larval salivary glands or gustatory receptors, then it is conceivable that high concentrations of His 6 -HFR1 may act as an antifeedant by binding to these structures; thus, they would not be ingested.…”