1 3 Novel parasitic nematode-specific protein of Setaria digitata largely 4 localized in longitudinal muscles, reproductive systems and developing 5 embryos 6 7 8 W.W.P. Rodrigo a Q1 , R.S. Dassanayake a,⇑ , D. Voronin b 9 a Department of Chemistry, Faculty of Science, University of Colombo, Colombo 03, Sri Lanka 10 b Molecular and Biochemical Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK 11 12 13 15 highlights 16 17  SDNP is a homolog of a group of novel 18 parasitic nematode-specific proteins. 19  SDNP expressed in all the stages of 20 parasitic nematode’s life. 21  SDNP is localized in both the nucleus 22 and cytoplasm. 23  SDNP may have roles in locomotion, 24 reproduction and embryogenesis. 25  SDNP is likely to be regulated by 26 reversible phosphorylation– 27 dephosphorylation. 28 graphical abstract 30 30 32 article info 33 Article history: 34 Received 6 November 2013 35 Received in revised form 11 February 2014 36 Accepted 5 March 2014 37 Available online xxxx 38 Keywords: 39 S. digitata novel protein (SDNP) 40 Parasitic nematodes 41 Tissue localization 42 Subcellular localization 43 44 abstract 45 Parasitic nematodes may have common properties in parasitizing the host which are conferred by related 46 parasitic proteins encoded by their genome. A novel protein characterized from bovine filarial nematode 47 Setaria digitata was found to be present only in the parasitic nematodes and expressed at all the stages of 48 the nematode’s life. In immunohistochemical staining using polyclonal antibodies prepared against 49 recombinant S. digitata protein, the highest expression of S. digitata novel protein (SDNP) was seen in 50 the longitudinal muscles of the body wall of adult males and females indicating its possible involvement 51 in parasite locomotion. Moderate expression was observed in the reproductive organs of both sexes while 52 showing gradual increase in the expression as the development of the reproductive tissue progressed 53 suggesting its role in tissue transformation in male and female reproduction. A low level of expression 54 was observed in the cuticle, syncytial hypodermis region, lateral line and the intestinal wall. Further, 55 the expression of SDNP was also seen in developing microfilaria within the uterus of female worms, 56 developing spermatozoa of males and different developmental stages of embryos implicating its involve- 57 ment in nematode growth and development. Subcellular localization of SDNP carried out in yeast, Pichia 58 pastoris using green fluorescence construct revealed that this protein localized mainly in the nucleus and 59 partly in the cytoplasm. Comprehensive bioinformatics analyses indicated that this protein contains a 60 nuclear localization signal, RNAP_Rpb7_N_like domain, regions that are homologous to a part of the 61 nuclear factor localization-like domain, interdomain linkers of muscle specific twitchin kinase of 62 Caenorhabditis elegans and calcium-dependent protein kinase isoform CDPK1 of Arabidopsis thaliana. http://dx.doi.org/10.1016/j.exppara.2014.03.009 0014-4894/Ó 2014 Elsevier Inc. All rights reserved. ⇑ Corresponding author. Fax: +94 11 2503367. E-mail address: rsdassanayake@gmail.com (R.S. Dassanayake). Experimental Parasitology xxx (2014) xxx–xxx Contents lists available at ScienceDirect Experimental Parasitology journal homepage: www.elsevier.com/locate/yexpr YEXPR 6832 No. of Pages 9, Model 5G 19 March 2014 Please cite this article in press as: Rodrigo, W.W.P., et al. Novel parasitic nematode-specific protein of Setaria digitata largely localized in longitudinal mus- cles, reproductive systems and developing embryos. Exp. Parasitol. (2014), http://dx.doi.org/10.1016/j.exppara.2014.03.009