title: Proteomic analysis of differentially expressed proteins in the two developmental stages of Ichthyophthirius multifiliis.
abstract: Ichthyophthirius is a severe disease of farmed freshwater fish caused by the parasitic ciliate Ichthyophthirius multifiliis (Ich). This disease can lead to considerable economic loss, but the protein profiles in different developmental stages of the parasite remain unknown. In the present study, proteins from trophonts and theronts of Ich were identified by isobaric tags for relative and absolute quantitation (iTRAQ). A total of 2300 proteins were identified in the two developmental stages, of which 1520 proteins were differentially expressed. Among them, 84 proteins were uniquely expressed in the theronts stage, while 656 proteins were expressed only in trophonts. The differentially expressed proteins were catalogued (assorted) to various functions of Ich life cycle, including biological process, cellular component, and molecular function that occur at distinct stages. Using a 1.5-fold change in expression as a physiologically significant benchmark, a lot of differentially expressed proteins were reliably quantified by iTRAQ analysis. Two hundred forty upregulated and 57 downregulated proteins in the trophonts stage were identified as compared with theronts. The identified proteins were involved in various functions of the I. multifiliis life cycle, including binding, catalytic activity, structural molecule activity, and transporter activity. Further investigation of the transcriptional levels of periplasmic immunogenic protein, transketolase, zinc finger, isocitrate dehydrogenase, etc., from the different protein profiles using quantitative RT-PCR showed identical results to the iTRAQ analysis. This work provides an effective resource to further our understanding of Ich biology, and lays the groundwork for the identification of potential drug targets and vaccines candidates for the control of this devastating fish pathogen.
authors.affiliation: Agriculture Ministry Key Laboratory of Healthy Freshwater Aquaculture, Key Laboratory of Fish Health and Nutrition of Zhejiang Province, Zhejiang Institute of Freshwater Fisheries, Huzhou, 313001, China.
authors.forename: Jia-Yun
authors.initials: JY
authors.lastname: Yao
authors.affiliation: Agriculture Ministry Key Laboratory of Healthy Freshwater Aquaculture, Key Laboratory of Fish Health and Nutrition of Zhejiang Province, Zhejiang Institute of Freshwater Fisheries, Huzhou, 313001, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Xu
authors.affiliation: Agriculture Ministry Key Laboratory of Healthy Freshwater Aquaculture, Key Laboratory of Fish Health and Nutrition of Zhejiang Province, Zhejiang Institute of Freshwater Fisheries, Huzhou, 313001, China.
authors.forename: Xue-Mei
authors.initials: XM
authors.lastname: Yuan
authors.affiliation: Agriculture Ministry Key Laboratory of Healthy Freshwater Aquaculture, Key Laboratory of Fish Health and Nutrition of Zhejiang Province, Zhejiang Institute of Freshwater Fisheries, Huzhou, 313001, China.
authors.forename: Wen-Lin
authors.initials: WL
authors.lastname: Yin
authors.affiliation: College of Animal Science and Technology, Jilin Provincial Engineering Research Center of Animal Probiotics, Jilin Agricultural University, Changchun, 130118, China.
authors.forename: Gui-Lian
authors.initials: GL
authors.lastname: Yang
authors.affiliation: Agriculture Ministry Key Laboratory of Healthy Freshwater Aquaculture, Key Laboratory of Fish Health and Nutrition of Zhejiang Province, Zhejiang Institute of Freshwater Fisheries, Huzhou, 313001, China.
authors.forename: Ling-Yun
authors.initials: LY
authors.lastname: Lin
authors.affiliation: Agriculture Ministry Key Laboratory of Healthy Freshwater Aquaculture, Key Laboratory of Fish Health and Nutrition of Zhejiang Province, Zhejiang Institute of Freshwater Fisheries, Huzhou, 313001, China.
authors.forename: Xiao-Yi
authors.initials: XY
authors.lastname: Pan
authors.affiliation: College of Animal Science and Technology, Jilin Provincial Engineering Research Center of Animal Probiotics, Jilin Agricultural University, Changchun, 130118, China. yaojiayun@126.com.
authors.forename: Chun-Feng
authors.initials: CF
authors.lastname: Wang
authors.affiliation: Agriculture Ministry Key Laboratory of Healthy Freshwater Aquaculture, Key Laboratory of Fish Health and Nutrition of Zhejiang Province, Zhejiang Institute of Freshwater Fisheries, Huzhou, 313001, China. sjinyu@126.com.
authors.forename: Jin-Yu
authors.initials: JY
authors.lastname: Shen
mesh_terms: D000818:Animals; D002347:Carps / Q000469:parasitology; D016770:Ciliophora Infections / Q000469:parasitology; D005393:Fish Diseases / Q000469:parasitology; D005786:Gene Expression Regulation; D016803:Hymenostomatida / Q000254:growth & development* / Q000378:metabolism*; D008018:Life Cycle Stages; D040901:Proteomics / Q000379:methods*; D053719:Tandem Mass Spectrometry / Q000379:methods
keywords: Differentially expressed proteins; Ichthyophthirius multifiliis; Proteomic analysis; iTRAQ