title: Transcriptome and analysis on the complement and coagulation cascades pathway of large yellow croaker (Larimichthys crocea) to ciliate ectoparasite Cryptocaryon irritans infection.
abstract: Large yellow croaker (Larimichthys crocea) is one of the most valuable marine fish in southern China. Given to the rapid development of aquaculture industry, the L. crocea was subjected to ciliate ectoparasite Cryptocaryon irritans. It therefore is indispensable and urgent to understand the mechanism of L. crocea host defense against C. irritans infection. In the present study, the extensively analysis at the transcriptome level for Cryptocaryoniasis in L. crocea was carried out. These results showed that 15,826,911, 16,462,921, and 15,625,433 paired-end clean reads were obtained from three cDNA libraries (A: 0 theronts/fish, B: 12,000 theronts/fish, and C: 24,000 theronts/fish) of the L. crocea immune-related tissues by Illumina paired-end sequencing technology. Totally, 30,509 unique transcript fragments (unigenes) were assembled, with an average length of 1715 bp. In B/A, C/A, and C/B pairwise comparison, 972, 900, and 1126 genes showed differential expression respectively. Differently expressed immune-related genes (DEIGs) were scrutinized, in B/A pairwise comparison, 48 genes showed differential expression, including 26 up-regulated genes and 22 down-regulated genes in B; in C/A pairwise comparison, there were 39 DEIGs, including 7 up-regulated genes and 32 down-regulated genes in C; in C/B pairwise comparison, 40 genes showed differential expression, including 11 up-regulated genes and 29 down-regulated genes in C. There were 16 DEIGs enriched KEGG pathways, in which the complement and coagulation cascades pathway was the top most DEIGs enriched pathway (B:A = 42; C:A = 28; C:B = 42). The coagulation and fibrinolytic system was in a highly active state after infected by C. irritans with non-lethal concentration; the alternative complement pathway may play an important role in the early stages of C. irritans infection. These results demonstrated that low-concentration infection can significantly induce the immunological response in fishes, however, when fishes were in fatal conditions, the immunity was suppressed.
authors.affiliation: Key Laboratory of East China Sea and Oceanic Fishery Resources Exploitation, Ministry of Agriculture, East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Shanghai, 200090, PR China. Electronic address: feige895@gmail.com.
authors.forename: Fei
authors.initials: F
authors.lastname: Yin
authors.affiliation: Key Laboratory of East China Sea and Oceanic Fishery Resources Exploitation, Ministry of Agriculture, East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Shanghai, 200090, PR China.
authors.forename: Quanxin
authors.initials: Q
authors.lastname: Gao
authors.affiliation: Key Laboratory of East China Sea and Oceanic Fishery Resources Exploitation, Ministry of Agriculture, East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Shanghai, 200090, PR China.
authors.forename: Baojun
authors.initials: B
authors.lastname: Tang
authors.affiliation: Key Laboratory of East China Sea and Oceanic Fishery Resources Exploitation, Ministry of Agriculture, East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Shanghai, 200090, PR China.
authors.forename: Peng
authors.initials: P
authors.lastname: Sun
authors.affiliation: Ningde Fufa Fisheries Co., Ltd., Ningde, Fujian Province, 352000, PR China; Key Laboratory of Healthy Mariculture for the East China Sea, Ministry of Agriculture, Fisheries College, Jimei University, Xiamen, 361021, PR China.
authors.forename: Kunhuang
authors.initials: K
authors.lastname: Han
authors.affiliation: Ningde Fufa Fisheries Co., Ltd., Ningde, Fujian Province, 352000, PR China; Key Laboratory of Healthy Mariculture for the East China Sea, Ministry of Agriculture, Fisheries College, Jimei University, Xiamen, 361021, PR China.
authors.forename: Weiqing
authors.initials: W
authors.lastname: Huang
mesh_terms: D000818:Animals; D016798:Ciliophora / Q000502:physiology; D016770:Ciliophora Infections / Q000235:genetics / Q000276:immunology / Q000469:parasitology / Q000662:veterinary*; D003165:Complement System Proteins / Q000235:genetics / Q000378:metabolism; D005393:Fish Diseases / Q000235:genetics* / Q000276:immunology / Q000469:parasitology; D029941:Fish Proteins / Q000235:genetics* / Q000378:metabolism; D007113:Immunity, Innate; D010473:Perciformes; D017423:Sequence Analysis, RNA / Q000662:veterinary; D059467:Transcriptome
chemical_list: D029941:Fish Proteins; D003165:Complement System Proteins
keywords: Complement and coagulation cascades pathway; Cryptocaryon irritans; Immune system; Larimichthys crocea; Transcriptome