Microarray analysis of gene expression changes in feeding female and male lone star ticks, Amblyomma americanum (L).

A collection of EST clones from female tick Amblyomma americanum salivary glands was hybridized to RNA from different feeding stages of female tick salivary glands and from unfed or feeding adult male ticks. In the female ticks, the expression patterns changed dramatically upon starting feeding, then changed again towards the end of feeding. On beginning feeding, genes possibly involved in survival on the host increased in expression as did many housekeeping genes.

Transcriptome analysis of the salivary glands of the female tick Amblyomma americanum (Acari: Ixodidae).

Ticks infest a wide range of hosts while bypassing their immune, inflammatory and haemostatic responses during their extended feeding, which may last for more than two weeks. Here, we present a transcriptome analysis of 3868 expressed sequence tags (ESTs) from three cDNA libraries generated from the salivary glands of adult female Ambyomma americanum ticks at different stages of feeding. We applied a normalization step for one library, significantly decreasing the abundance of mitochondrial sequences amongst the 2292 sequences from the normalized library.

The sodium-dependent D-glucose transport protein of Helicobacter pylori.

Helicobacter pylori is a gram-negative pathogenic microaerophile with a particular tropism for the mucosal surface of the gastric epithelium. Despite its obligatory microaerophilic character, it can metabolize D-glucose and/or D-galactose in both oxidative and fermentative pathways via a Na(+)-dependent secondary active transport, a glucokinase and enzymes of the pentose phosphate pathway. We have assigned the Na(+)-dependent transport of glucose to the protein product of the H.

Gene expression in male tick salivary glands is affected by feeding in the presence of females.

In this study, we have compared gene expression in the salivary glands of male Dermacentor andersoni ticks fed in the presence or absence of females to that in unfed males. We have established that the patterns of expression are different using arbitrarily primed polymerase chain reaction following reverse transcription of RNA (RAP-PCR) and differential display. Our results indicate a significant difference in salivary gland gene expression between fed and unfed males and also between males fed in the presence of females versus males fed in the absence of females.

Application of RNA interference in tick salivary gland research.

Ticks are obligate ectoparasites that feed on a variety of hosts including mammals, birds and reptiles. Prolonged attachment on the host and an ability to transmit a wide variety of pathogens are the special features of tick feeding. Salivary glands are the major route for secretion of excess fluid, several proteins, and factors that counteract the host immune response and hence play a significant role in the success of tick feeding.