African Journal of

  • Abbreviation: Afr. J. Biotechnol.
  • Language: English
  • ISSN: 1684-5315
  • DOI: 10.5897/AJB
  • Start Year: 2002
  • Published Articles: 12481

Full Length Research Paper

Development of an RNA-interference procedure for gene knockdown in the poultry red mite, Dermanysus gallinae: Studies on histamine releasing factor and Cathepsin-D

Lucy M. Kamau1,2*, Harry W. Wright3, Alasdair J. Nisbet3 and Alan S. Bowman1
  1University of Aberdeen, School of Biological Sciences, Aberdeen, AB24 2TZ, Scotland, UK. 2Department of Zoological Sciences, Kenyatta University, P. O Box 43844, 00100, Nairobi, Kenya. 3Parasitology Division, Moredun Research Institute, Midlothian EH26 OPZ, Scotland, UK.
Email: [email protected], [email protected].

  •  Accepted: 16 November 2012
  •  Published: 31 March 2013



The poultry mite, Dermanyssus gallinae, is a parasite of fowl and birds worldwide, causing huge economic losses in production systems. We investigated gene-knockdown approach in identifying potential vaccine antigens, targeting Histamine Releasing Factor (HRF) and Cathepsin D (C), through immersion in dsRNA derived from the two genes, for 7 and 16 h respectively, alongside LacZ control. Quantitativereverse transcriptase (RT)-PCR was used to estimate the extent of gene knockdown. The results show successful knockdown of HRF target after 16 h of immersion in dsRNA. It is suggested that optimization of delivery methods for dsRNA and targeting more genes could enhance knockdown.


Key words: Dermanyssus gallinae (Acari: Astigmata), RNA interference (RNAi), gene silencing, histamine releasing factor, Cathepsin D.


 HRF, Histamine releasing factor; Dg-CatD, Dermanyssus gallinae cathepsin D; C, cathepsin D; RNAi, RNA interference; dsRNA, double stranded RNA;FEC, faecal egg countssiRNAs, small interfering RNA molecules