How to cite this article: Vet. Res. (2010) 41:16
DOI: 10.1051/vetres/2009064

Feeding-associated gene expression in sheep scab mites (Psoroptes ovis)

Carol M. Mcnair¹, Peter F. Billingsley^{2, 3}, Alasdair J. Nisbet¹ and Dave P. Knox<sup>1

1</sup>  Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, nr Edinburgh EH26 0PZ, United Kingdom
²  School of Biological Sciences, University of Aberdeen, Aberdeen AB24 2TZ, United Kingdom
³  Sanaria Inc., 12115 Parklawn Drive, Ste L, Rockville, MD 20852-1730, USA

Received 4 August 2009; accepted 22 October 2009; published online 27 October 2009

Abstract - The mite Psoroptes ovis is the causative agent of sheep scab. Although not usually fatal, the disease can spread rapidly and is a serious animal welfare concern. Vaccine development against ectoparasites has primarily focussed on two sources of candidate vaccine antigens – “exposed” antigens that are secreted in saliva during feeding on a host and “concealed” antigens that are usually expressed in the parasite gut and may be involved in digestion. Here, we sought to identify genes encoding proteins important for mite feeding and digestion by a subtractive suppressive hybridisation approach comparing mRNA transcript abundance in “fed” and “starved” mites. The study identified a variety of genes which are up-regulated by feeding mites. These included group 1, 5, 7 and 13 allergens including the previously described cysteine protease Pso o 1. In addition, numerous novel genes were identified here including some encoding potential salivary gland proteins and others encoding proteins which may facilitate feeding such as a serum opacity factor. An olfactory receptor-like protein was identified in the starved mite population which may help the mite to identify a host.

Key words: Psoroptes / sheep / gene / protein / feeding

Corresponding author: dave.knox@moredun.ac.uk

© INRA, EDP Sciences 2009