title: Molecular cloning and characterization of interferon regulatory factor 1 (IRF-1), IRF-2 and IRF-5 in the chondrostean paddlefish Polyodon spathula and their phylogenetic importance in the Osteichthyes.
abstract: The interferon regulatory factor (IRF) with its 10 members is a very important gene family related to innate immunity. Currently, most fish IRFs reported are from bony fish (teleosts). Cloning and sequencing of IRFs from chondrosteans, the so-called "ancient fish" including sturgeon, paddlefish, bichir and gar, are absent from the literature. In this study, three IRF genes PsIRF-1, PsIRF-2 and PsIRF-5, were cloned and characterized from the paddlefish (Polyodon spathula). PsIRF-1 includes an open reading frame (ORF) of 972 bp that encodes a putative protein of 324 amino acids; PsIRF-2 includes an ORF of 1023 bp encoding 341 amino acids and PsIRF-5 includes an ORF of 1491 bp that encodes 497 amino acids. The PsIRF-5 gene structure is similar to those in mammals but differs from those in teleosts in the first and second exons. Phylogenetic studies of the putative amino acid sequences of PsIRF-1, PsIRF-2 and PsIRF-5 based on the neighbor-joining and Bayesian inference method for Osteichthyes found widely accepted inter-relationships among actinopterygians and tetrapods. Reverse Transcription Polymerase Chain Reaction (RT-PCR) analysis of PsIRF-1, PsIRF-2 and PsIRF-5 in different paddlefish tissues shows higher levels of expression in gill, spleen and head kidney. Poly (I: C) (polyinosinic-polycytidylic acid) stimulation in vivo up-regulated PsIRF-1 and PsIRF-2 expression, while PsIRF-5 gene expression did not respond to the challenge of Poly (I: C).
authors.affiliation: State Key Lab of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei Province 430071, China.
authors.forename: Gan
authors.initials: G
authors.lastname: Xiaoni
authors.forename: Chen
authors.initials: C
authors.lastname: Zhuo
authors.forename: Wang
authors.initials: W
authors.lastname: Xuzhen
authors.forename: Wang
authors.initials: W
authors.lastname: Dengqiang
authors.forename: Chen
authors.initials: C
authors.lastname: Xinwen
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D005075:Biological Evolution; D003001:Cloning, Molecular; D029941:Fish Proteins / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D005399:Fishes; D005786:Gene Expression Regulation / Q000276:immunology; D007113:Immunity, Innate; D007114:Immunization; D050856:Interferon Regulatory Factor-1 / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D050836:Interferon Regulatory Factor-2 / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D050835:Interferon Regulatory Factors / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D008969:Molecular Sequence Data; D010802:Phylogeny; D011070:Poly I-C / Q000276:immunology
chemical_list: D029941:Fish Proteins; D050856:Interferon Regulatory Factor-1; D050836:Interferon Regulatory Factor-2; D050835:Interferon Regulatory Factors; D011070:Poly I-C