Expression Profile Of Odorant Receptors In Brain, Gut And Reproductive Tissues In Male And Female Glossina Morsitans Morsitans

Glossina morsitans morsitans are vectors of Animal African Trypanosomiasis (nagana) and Human African Trypanosomiasis (sleeping sickness). Glossina uses odorant receptors (Ors) expressed within the olfactory receptor neurons to identify chemical cues within the environment, locate hosts and find larviposition sites and mating partners. Most Ors have been identified in insects' olfactory tissues but little is known about the potential functions of Ors in non-olfactory organs. In the present study, we determine the expression profile of 46 Ors in male and female G. m. morsitans brain, gut and reproductive tissues using quantitative polymerase chain reaction. Our results indicate that 38 Or genes were detected in the male brain and gut, 37 in reproductive tissues while the number identified in the female included 44 in brain, 22 in gut and 40 in reproductive tissue. The Or genes were abundantly distributed in both male and female brain, gut and reproductive tissues at different fold expression levels. Quantitative real time PCR revealed that 4 Or genes (GmmOr19, GmmOr28, GmmOr30, GmmOr31) were significantly highly expressed in the male G. m. morsitans brain while the gut had 6 Ors (GmmOr7, GmmOr12, GmmOr32, GmmOr34, GmmOr42, GmmOr44) and the testis and accessory glands had 3 Or genes (GmmOr32, GmmOr44, GmmOr46) significantly highly expressed. In the female G. m. morsitans, the Ors that were significantly expressed were 2 in the brain (GmmOr25, GmmOr27), 3 both in the gut (GmmOr17, GmmOr33, GmmOr35) and reproductive tissues (GmmOr9, GmmOr22, GmmOr27).This results provides insight on the expression profile of Or genes in non-olfactory organs (brain, gut and reproductive tissues) in male and female G. m. morsitans and open avenues to investigate the possible role of the Or genes that were significantly expressed, which could provide targets that could be explored to control Glossina and the devastating trypanosomiasis disease. (C) 2020 The Authors. Published by Elsevier B.V. on behalf of African Institute of Mathematical Sciences / Next Einstein Initiative.