title: A murrel interferon regulatory factor-1: molecular characterization, gene expression and cell protection activity.
abstract: In this study, we have reported a first murrel interferon regulatory factor-1 (designated as Murrel IRF-1) which is identified from a constructed cDNA library of striped murrel Channa striatus. The identified sequence was obtained by internal sequencing method from the library. The Murrel IRF-1 varies in size of the polypeptide from the earlier reported fish IRF-1. It contains a DNA binding domain along with a tryptophan pentad repeats, a nuclear localization signal and a transactivation domain. The homologous analysis showed that the Murrel IRF-1 had a significant sequence similarity with other known fish IRF-1 groups. The phylogenetic analysis exhibited that the Murrel IRF-1 clustered together with IRF-1 members, but the other members including IRF-2, 3, 4, 5, 6, 7, 8, 9 and 10 were clustered individually. The secondary structure of Murrel IRF-1 contains 27% α-helices (85 aa residues), 5.7% β-sheets (19 aa residues) and 67.19% random coils (210 aa residues). Furthermore, we predicted a tertiary structure of Murrel IRF-1 using I-Tasser program and analyzed the structure on PyMol surface view. The RNA structure of the Murrel IRF-1 along with its minimum free energy (-284.43 kcal/mol) was also predicted. The highest gene expression was observed in spleen and its expression was inducted with pathogenic microbes which cause epizootic ulcerative syndrome in murrels such as fungus, Aphanomyces invadans and bacteria, Aeromonas hydrophila, and poly I:C, a viral RNA analog. The results of cell protection assay suggested that the Murrel IRF-1 regulates the early defense response in C. striatus. Moreover, it showed Murrel IRF-1 as a potential candidate which can be developed as a therapeutic agent to control microbial infections in striped murrel. Overall, these results indicate the immune importance of IRF-1, however, the interferon signaling mechanism in murrels upon infection is yet to be studied at proteomic level.
authors.affiliation: Division of Fisheries Biotechnology & Molecular Biology, Department of Biotechnology, Faculty of Science and Humanities, SRM University, Kattankulathur, Chennai, 603 203, Tamil Nadu, India, jesuaraj@hotmail.com.
authors.forename: Jesu
authors.initials: J
authors.lastname: Arockiaraj
authors.forename: Akila
authors.initials: A
authors.lastname: Sathyamoorthi
authors.forename: Venkatesh
authors.initials: V
authors.lastname: Kumaresan
authors.forename: Rajesh
authors.initials: R
authors.lastname: Palanisamy
authors.forename: Mukesh Kumar
authors.initials: MK
authors.lastname: Chaurasia
authors.forename: Prasanth
authors.initials: P
authors.lastname: Bhatt
authors.forename: Annie J
authors.initials: AJ
authors.lastname: Gnanam
authors.forename: Mukesh
authors.initials: M
authors.lastname: Pasupuleti
authors.forename: Abirami
authors.initials: A
authors.lastname: Arasu
mesh_terms: D016980:Aeromonas hydrophila; D000818:Animals; D044744:Aphanomyces; D003001:Cloning, Molecular; D019295:Computational Biology; D029941:Fish Proteins / Q000235:genetics / Q000276:immunology*; D005399:Fishes / Q000235:genetics* / Q000276:immunology; D015870:Gene Expression; D015723:Gene Library; D005822:Genetic Vectors; D050856:Interferon Regulatory Factor-1 / Q000235:genetics / Q000276:immunology*; D029141:Novirhabdovirus; D010957:Plasmids; D011070:Poly I-C / Q000235:genetics / Q000378:metabolism; D017434:Protein Structure, Tertiary; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D017422:Sequence Analysis, DNA; D013154:Spleen / Q000166:cytology / Q000821:virology; D014611:Vaccination
chemical_list: D029941:Fish Proteins; D050856:Interferon Regulatory Factor-1; D012333:RNA, Messenger; D011070:Poly I-C